The Disastrous Life of Saiki K.
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|The Disastrous Life of Saiki K.|
First tankōbon volume featuring Kusuo Saiki
|Genre||Comedy , science fiction |
|Written by||Shūichi Asō|
|Magazine||Weekly Shōnen Jump|
|Original run||May 14, 2012 – February 26, 2018|
|Volumes||26 ( List of volumes )|
|Anime television series|
|Directed by||Hiroaki Sakurai|
|Written by||Michiko Yokote|
|Music by||Psychic Lover|
|Studio||J.C.Staff , Egg Firm|
|Original network||TV Tokyo , TV Aichi , TV Osaka , TV Hokkaido|
|Original run||July 4, 2016 – June 27, 2018|
|Episodes||48 ( List of episodes )|
|Saiki Kusuo no Psi Nan: Shijō Psi Dai no Psi Nan!?|
|Developer||Bandai Namco Studios|
|Publisher||Bandai Namco Entertainment|
|Released||November 10, 2016|
|Written by||Shūichi Asō|
|Magazine||Weekly Shōnen Jump|
|Original run||March 5, 2018 – present|
|Anime and Manga portal|
The Disastrous Life of Saiki K. ( Japanese : 斉木楠雄のΨ難 Hepburn : Saiki Kusuo no Sai-nan) is a Japanese gag manga series written and illustrated by Shūichi Asō. The series began serialization in Shueisha ‘s Weekly Shōnen Jump from June 2012. An anime television adaptation by J.C.Staff and Egg Firm began airing on July 4, 2016. A live-action film directed by Yuichi Fukuda and starring Kento Yamazaki at Columbia Pictures ( Sony Pictures Entertainment Japan ) and Asmik Ace was released on October 21, 2017. 
- 1 Plot
- 2 Characters
- 2.1 Saiki family
- 2.2 PK Academy
- 2.3 Others
- 3 Media
- 3.1 Manga
- 3.1.1 Volumes
- 3.2 Light Novel
- 3.3 Anime
- 3.4 Video games
- 3.5 Live-action film
- 3.1 Manga
- 4 Notes
- 5 Works cited
- 6 References
- 7 External links
Plot[ edit ]
Kusuo Saiki is a high school student who was born with all manner of psychic abilities, including telepathy, psychokinesis, teleportation, and more. Despite having all these powers, Saiki faces all kinds of hardships and tries to avoid attention as much as possible. The story follows Saiki as he attempts to secretly use his powers to live a normal high school life while dealing with his less than ordinary classmates at P.K. Academy.
Characters[ edit ]
Saiki family[ edit ]
- Kusuo Saiki (斉木 楠雄 Saiki Kusuo)
- Voiced by: Shintarō Asanuma  (vomic, flash anime), Hiroshi Kamiya (TV anime),  (Japanese); Jerry Jewell  (English)
- The viewpoint character and narrator of the series, Kusuo Saiki is a high school student who was born with all manner of psychic abilities despite having very ordinary biological parents. Because of the misery that comes from the attention he receives as a psychic, Kusuo desires a normal, plain life, keeping average grades and performance in sports activities. He uses telepathy to read people’s minds, but he can also share telepathy with others. His other abilities include telekinesis , levitation , x-ray vision , Ch. P1 clairvoyance , Ch. P6 astral projection , Ch. P7 pyrokinesis , Ch. 2 mind control (convincing someone that certain things in the world are normal, or that they are seeing someone else’s image), Ch. 10 psychometrics , Ch. 17 and invisibility. Ch. 20 He can teleport things, but has to replace the item with something of equal value. Ch. P5 He can sometimes pick up other psychic abilities temporarily like Toritsuka’s ability to see ghosts. Ch. 18 He has dark pink hair, Ch. 10 with two antennae on his head that people think are hair ornaments, but they actually regulate his constantly growing powers that would otherwise go out of control and destroy things as well as cause global catastrophes. Ch. 23, 59 He can transform into animals or into a girl that he names Kusuko. Ch. 37, 79 Kusuo wears glasses so that his gaze doesn’t turn someone to stone . Ch. 71-72 His favorite snack is coffee jelly . Ch. 27 He is vulnerable to bugs, especially cockroaches , [a] because he cannot read their minds and predict their actions. Ch. 15
- Kuniharu Saiki (斉木 國春 Saiki Kuniharu)
- Voiced by: Mitsuo Iwata  (Japanese); Chuck Huber  (English)
- Kusuo’s father, who has to suck up to his employers so much that he has gained a taste for licking shoes . Ch. 1 He works as an editor for a manga publishing company that appears to be a knock-off of Shueisha . Ch. 62
- Kurumi Saiki (斉木 久留美 Saiki Kurumi)
- Voiced by: Rikako Aikawa  (Japanese); Morgan Garrett  (English)
- Kusuo’s mother whom he states is “the one who keep him from turning into dark side” because of her kindness, but can be scary when needed that Kusuo won’t be able to defy her. Ch. 1 She is allergic to cats. Ch. 36 Her maiden name is also Saiki. Ch. 92 She can be rather naive and air-headed at times. Ch. 133
- Kusuo’s grandparents
- Voiced by: Koichi Yamadera (Kumagoro) and Rie Tanaka (Kumi)
- Kumagoro Saiki and Kumi Saiki are Kusuo’s maternal grandparents. Kumagoro has a classic tsundere personality, that is, he is hard on the outside, but soft on the inside. He is very fond of his daughter, but dislikes his son-in-law, often beating him up or sending him away to run errands. He wants to get to know his grandson better. Kumi acts fairly young for her age, with her choice of fashionable clothes and her gyaru (gal) speech. Ch. 92-94, 116 In the anime they were voiced by Koichi Yamadera and Rie Tanaka who happen to be a real-life married couple. 
- Kusuke Saiki (斉木 空助 Saiki Kūsuke)
- Voiced by: Kenji Nojima  (Japanese); Chris Patton (English)
- Kusuke is Kusuo’s older brother by two years. He is a super genius who invents devices and machines, but lacks psychic abilities and thus always loses in any sort of competition with his brother. When he was 14, he moved to England where he has been a doctoral candidate at Cambridge University . He invents a “telepath canceler” so that Kusuo cannot read his thoughts. Ch. 103-107 After graduating from university, he moves in with his grandparents. Ch. 160
PK Academy[ edit ]
- Riki Nendo (燃堂 力 Nendō Riki)
- Voiced by: Kenta Miyake  (vomic, flash anime), Daisuke Ono  (Japanese); David Wald  (English)
- A large, muscular student with a Mohawk hairstyle, a scar over his left eye and a cleft chin . Nendo is the only student at PK Academy whose mind Saiki cannot read, simply because he is too much of an idiot. As such, Saiki often fears his overly friendly and carefree nature as he cannot predict his actions. Ch. 2 However, Nendo is fond of Saiki and considers him his best buddy. His family members have the same faces as him, with his deceased father with a scar over his right eye instead of Riki’s left, and his mother Midori with scars over both eyes. Ch. P4, 16, 46 He has a horrible singing voice. Ch. 90
- Shun Kaido (海藤 瞬 Kaidō Shun)
- Voiced by: Takuya Eguchi  (vomic, flash anime), Nobunaga Shimazaki  (Japanese); Micah Solusod  (English)
- A classmate who calls himself “The Jet-Black Wings” (漆黒の翼 Shikkoku no Tsubasa), thinking he is secretly living as a rebel in a fantasy world ruled by an evil conspiracy organization called Dark Reunion. Although, while still so much attached to his delusional mind, he slowly builds a normal human relationship with his schoolmates despite his chūnibyō antics popping up. Ch. P6, 3 His mother is very strict on his school work. Ch. 51, 105 Kaido has low physical stamina and strength as shown in several stories. Ch. 48, 86, 106, 112 He also has no sense of direction. Ch. 74
- Matsuzaki (松崎)
- Voiced by: Taro Yamaguchi
- A gym teacher and school guidance counselor. A strict but kind teacher that everyone fears, but is liked by Saiki because he frequently keeps Saiki’s school life at peace as he keeps people from troubling Saiki. Ch. 2, 37
- Kokomi Teruhashi (照橋 心美 Teruhashi Kokomi)
- Voiced by: Ai Kayano (Japanese); Tia Ballard  (English)
- A self-proclaimed beautiful girl who is part of Saiki’s class. She acts modest in public as that increases her appeal, but secretly loves the attention that is lavished upon her and all the favors that the guys are willing to do for her. When Saiki does not treat her like that and even ignores her, she becomes obsessed with making him react or show admiration, like saying “Oh wow” (おっふ Offu) at her. Ch. 5, 13, 29, 54 She has a fan club called the Kokomins. Ch. 101 In later chapters, it is revealed that her charisma does not affect guys who strongly love someone else (Saiki’s father), those with pure eyes that view everyone equally (Hairo), or those who can see her true nature (Saiki). Her one weakness is with little kids such as Yuuta who exhibit all three of those characteristics. Ch. 87 In one of the chapters, it is shown she harbors a list of things that people should never say to her. Ch. 87 Despite being wooed by guys like Metori Saiko that fit her ideal financial expectations, she develops feelings of love for Saiki. Ch. 114-115 In the anime, she is typically bathed in a bright yellow glow.
- Chiyo Yumehara (夢原 知予 Yumehara Chiyo)
- Voiced by: Yukari Tamura (Japanese); Jill Harris  (English)
- Saiki’s classmate who has a romanticized perspective on relationships despite having a history of poor choices of boyfriends. Ch. 109, 140, 162 She has short brown hair and wears a hairband. After failing to attract Saiki with her romantic comedy manga-like encounters, she dates the sweet-talking Takeru, but breaks up with him after she realizes he uses the same pick-up lines and other annoying habits. Ch. 5, 21 Chiyo becomes friends with Kokomi, but suspects they both have crushes on Saiki. Ch. 54 Her attention is diverted to Shun Kaido, who saves her from being further belittled by some guys at the beach during the school trip, but who is oblivious that he is even in a relationship with her. Ch. 54, 60, 96 Chiyo is the subject of some side stories involving weight loss and obesity, Ch. 82, 123 Asō has mentioned he has been working hard to draw the girls to appeal to the seinen demographic. Ch. 56 notes
- Kineshi Hairo (灰呂 杵志 Hairo Kineshi)
- Voiced by: Satoshi Hino (Japanese); Kyle Phillips  (English)
- Saiki’s class representative is an overly hot-blooded, energetic, passionate student who enjoys sports and is constantly trying to get other people motivated. Ch. 6 He has bright red hair and typically wears a nasal strip . Due to his nature, he is well-trusted by his classmates. Ch. 19 A running gag is that whenever he trips his shorts drop and his butt is exposed . Ch. 6, 24
- Reita Toritsuka (鳥束 零太 Toritsuka Reita)
- Voiced by: Natsuki Hanae (Japanese); Joel McDonald  (English)
- A medium and one of two people outside of Saiki’s family to know of Saiki’s abilities. He has the ability to see spirits, but is only interested in using his ability to attract girls and to become rich. His guardian ghost is Nendo’s late father. Ch. 18 He later lets other spirits possess his body. Ch. 52, 79 Toritsuka starts an Occult Club at school. Ch. 96 Aiura, Toritsuka, and Saiki constitute the “Psychic Trio” at PK Academy, albeit this is a characterization to which Saiki objects.
- Chisato Mera (目良 千里 Mera Chisato)
- Voiced by: Maaya Uchida  (Japanese), Megan Shipman (English)
- A glasses-wearing classmate of Saiki’s who works multiple jobs to make ends meet, include part-time at a cafe that Saiki frequents. Ch. 47 A running gag is that she craves free food, and binge eats whenever she can. Ch. 57-58, 97
- Aren Kuboyasu (窪谷須 亜蓮 Kuboyasu Aren)
- Voiced by: Yoshimasa Hosoya  (Japanese)
- A transfer student with rectangular-framed glasses and purple hair Vol. 9 author’s notes who used to be a delinquent in his former school. He tries to put his past behind him by being calm and collected, yet has a short temper whenever he sees bullying or whenever someone is being rude to him. Ch. 65-66
- Metori Saiko (才虎 芽斗吏 Saiko Metori)
- Voiced by: Masaya Matsukaze (Japanese); Adam Gibbs (English)
- A rich and smug descendant of the top-notch Saiko Conglomerate who later transfers to PK Academy, ends up falling in love with Kokomi, who declines his offer because she still likes Saiki. Ch. 114-115 At first, he became to resent Saiki but latter just kind of hangs around and tries to make people jealous of how rich and great he is. Ch. 137-138
- Imu Rifuta (梨歩田 依舞 Rifuta Imu)
- Voiced by: M.A.O 
- A pretty first-year student with light hair and pigtails who has a strong desire for recognition and takes pride in her appearance to charm the boys, however, she realizes she does not match up to Kokomi. Ch. 143 She shows interest in Saiki in order to upstage Kokomi, and Saiki had hoped for the same so that the two girls would eventually leave him alone, but it did not work out. Ch. 149 She later turns her affections toward Kokomi when she sees that Kokomi has struggles in her relating to Saiki. S2 ep 12
- Mikoto Aiura (相卜 命 Aiura Mikoto)
- Voiced by: Eri Kitamura 
- Mikoto is a gyaru with blonde hair, tan skin, and big breasts who transfers to Saiki’s class.   She is a fortune teller who can read the future and determine someone’s love compatibility, often accompanied with spontaneous gestures and movements that she makes up to get her in the mood. Saiki realizes her powers are for real after she accurately assesses his classmates. Her goal is to find her true love, and starts becoming interested in Saiki but dislikes Toritsuka. She can read people’s auras, although Saiki’s aura is so intense that she cannot read his. Ch. 162-163 After Saiki is forced to reveal his powers to her in order to save Chiyo, she becomes interested in Saiki, and agrees to keep his powers a secret. She, Saiki and Toritsuka constitute a “psychic trio”, much to Saiki’s dismay.  S2 ep 11
Others[ edit ]
- Uryoku Chono (蝶野 雨緑 Chōno Uryoku)
- Voiced by: Showtaro Morikubo  (Japanese), Austin Tindle (English)
- A street magician who performs with his partner Michael. He sometimes relies on Saiki to help him with his magic tricks. Ch. P3, 14 His real name is Kōta Nakanishi (中西 宏太 Nakanishi Kōta) Ch. 15 Two years prior, Chono used to work for a publishing company when he met Nendo’s mother, but they divorced after he lost his job and didn’t pick up any further work prior to becoming a magician. Ch. 46
- Nendo’s parents
- Riki Nendo’s deceased father is still hanging around as a ghost. He looks exactly like Riki except that he has his vertical scar over his right eye instead of his left. He is the guardian ghost for Toritsuka. Because he is a ghost, he no longer maintains any memories of what he himself looks like or that he’s related to the Nendos. Ch. P4, 16, 46 Riki’s mother Midori also looks exactly like Riki except she has a vertical scar over each of her eyes, and she has curly hair. She works multiple jobs; and had married Chono briefly. Ch. P4, 16, 46
- Amp (アンプ Anpu)
- Voiced by: Yoshitsugu Matsuoka
- An arrogant street cat who was saved by Kusuo when he was trapped between two buildings. Ch. 36 After that, he got attached to Kusuo and, despite Kusuo’s continuous rejections, started to frequents the Saiki House where Kusuo’s father feeds him. Ch. 49 Though Saiki usually finds Amp annoying, he changes his attitude toward him after Amp saved him from a cockroach while Saiki was shrunk down. Ch. 89
- Makoto Teruhashi (照橋 信 Teruhashi Makoto) / Touru Mugami (六神 通 Mugami Tōru)
- Voiced by: Tomoaki Maeno  (Japanese), Brandon McInnis (English)
- Makoto is Kokomi’s older brother and a top teen actor with the stage name Toru Mugami. He has a serious sister complex and hates it when Saiki is near her. Ch. 41, 43
- Yūta Iridatsu (入達 遊太 Iridatsu Yūta)
- Voiced by: Yumiko Kobayashi
- A five-year-old boy who first encounters Saiki Kusuo using his powers to get his balloon back. He is convinced that Saiki is his favorite comic book hero, Cyborg Cider-man Version 2. His family moves next door to the Saikis. Ch. 53
Media[ edit ]
Manga[ edit ]
The series began serialization in Shueisha ‘s Weekly Shonen Jump magazine on May 14, 2012. The first collected tankōbon volume was published on September 4, 2012, with 25 volumes released as of April 2018.  The series ended serialization on February 26, 2018.  Shueisha later revealed that a 4-panel sequel would begin serialization on March 5, 2018. 
Saiki has had many crossovers with other jump manga characters from other jump works such as Gin Tama and Assassination Classroom. in which he and Koro-sensei has had an ongoing rivalry going over Irumanju as seen as a bonus or extra in chapters 40 and 62.
Volumes[ edit ]
|0||May 2, 2012 ||ISBN 978-4-08-870455-5|
|A collection of one-shots about Saiki that were published in Weekly Shonen Jump, Jump Special, and Jump Square.|
Kusuo Saiki is a high school student who was born with all sorts of psychic abilities from levitation to telepathy . Instead of trying to take advantage of his powers in any way possible, he finds the powers to be annoying, and tries to keep them a secret in order to live a normal life. Riki Nendo, a delinquent punk-looking classmate who bugs Saiki, is accused to stealing wallets from their classmates’ bags. Saiki determines it is someone else. Saiki is being bullied, when Nendo tries to save him. He uses x-ray vision and meets a street magician named Chono. His precognition vision shows a memorial picture of Nendo, so Saiki tries to hang out with Nendo for the day, only to learn that the picture was actually of Nendo’s late father. He uses teleportation to help Chono with a magic trick in which Chono’s new assistant was going to make Chono look bad. He meets classmate Shun Kaido, who claims he has seen a weird student with psychic powers. He uses astral projection to possess Nendo’s body when the latter was knocked out by a baseball.
|1||September 4, 2012 ||ISBN 978-4-08-870504-0|
|Kusuo Saiki has an abundance of psychic powers, but prefers to remain a low-key high school student. He intervenes in a feud between his parents by forcing telepathy between them so they learn their true feelings of each other. He talks about how he used to show off his powers in kindergarten, but that led to all sorts of trouble, so he keeps it a secret. During the high school entrance day, he and Riki Nendo help Takahashi to the infirmary but it turns out Takahashi had faked his illness to get out of the event. Shun Kaido, a classmate who thinks he is a special student being pursued by an organization called Dark Reunion but is actually a chūnibyō , deals with a snake that got loose in a classroom. Kaido, Nendo, and Saiki help a little girl find her dog. Saiki tries to fend away the romantic advances of classmate Chiyo Yumehara. Saiki has to play dodgeball without revealing his powers yet help out his team which consists of sports enthusiast Kineshi Hairo. Saiki and Nendo talk a guy out of committing suicide.|
|2||December 4, 2012 ||ISBN 978-4-08-870556-9|
|Saiki helps his parents rearrange furniture and rooms. Saiki explains how he has used mind control to influence how people see him and his abilities that have been made public. Saiki watches as Kaido is swindled of his valuables by another student who was role-playing being related to the organization against Dark Reunion. Nendo and the guys take Saiki to the beach; Nendo fails to pick up a girl, but when the girl is later drowning, Nendo and the others rescue her thanks to Saiki’s secret help. Kokomi Teruhashi, a self-proclaimed “perfect girl” who is beautiful and kind, is shocked when Saiki pays absolutely no attention to her, despite her multiple attempts to greet him. Saiki tries to rescue Chono from a dangerous televised magic trick. While house sitting for his parents, Saiki is bothered by cockroaches. Saiki and Kaido notice Nendo is acting rather strange, so they follow them through town. Reita Toritsuka, a fellow psychic who can see ghosts, wants Saiki to disciple him. Toritsuka enrolls in Saiki’s school where he tries to become popular with the girls by telling them about their guardian ghosts.|
|3||January 4, 2013 ||ISBN 978-4-08-870621-4|
|Saiki helps Hairo build a gate for the school’s cultural festival . Saiki uses invisibility in order to leave school so he can watch a television program, but his classmates block his way out. Saiki tries to help Chiyo maintain a relationship with her boyfriend despite the latter’s major flaws. Saiki participates in the school’s sports festival, but during one of the events, Nendo accidentally removes Saiki’s antenna and he loses control of his powers. Although he gets his antenna back, he isn’t feeling that well. The school holds a disaster evacuation drill, Saiki buys a premium coffee jelly but later sacrifices it to retrieve a baseball lost by a kid. Saiki learns of a popular fortune-teller and discovers she is scamming others especially Kaido. Teruhashi joins the guys to a supposedly good ramen shop that appears to be really low quality.|
|4||May 2, 2013 ||ISBN 978-4-08-870652-8|
|Reita Toritsuka shares his story about talking with ghosts and helping a girl find her gym clothes. Saiki uses his precognition power to stop a chain of events leading to an explosion. Saiki attends the Jump Festa convention. When Nendo visits the Saikis and reveals he has never met Santa before, Saiki’s father dresses up as one and fools him into thinking he’s really Santa. During the New Years shrine visit, Saiki’s parents are shocked that Saiki has made a number of friends from school that they invite him over, but when Saiki’s mother accidentally reveals that Saiki is a psychic, Saiki must erase his schoolmates’ memories afterwards. Saiki meets an arrogant cat who is stuck between the walls of two buildings. Saiki’s classmates try to trick the strict physical education teacher Matsuzaki-sensei, but Saiki foils their plan. Saiki’s friends deal with chocolates on Valentine’s Day . Saiki is bothered by Nendo’s father who is a ghost, that he goes to Toritsuka for help. Saiki tries to help his mother from being scammed by a door-to-door salesman into buying useless products.|
|5||July 4, 2013 ||ISBN 978-4-08-870768-6|
|Saiki discovers a ring that blocks his telepathy, so he uses it to go to a movie theater, but finds himself seated next to Kokomi, who is then met with teen actor Toru Mugami. During finals, Saiki notices Nendo is resorting to rolling a pencil to get random answers, yet somehow he does well on his exam. Toru, who turns out to be Kokomi’s older brother, visits Saiki and tells him to stay away from his sister, revealing that he has a huge sister complex. Chono has Saiki assist in his next magic show in order to impress his ex-wife. Nendo shows up and volunteers to be in the next act, and it is revealed Chono’s ex-wife is Nendo’s mother. Saiki helps out classmate Chisato Mera, who is secretly working as a waitress and other random jobs to make ends meet, be accepted by gym teacher Matsuzaki-sensei. During the fitness test, Hairo finds he is being outdone by Nendo. Saiki helps the cat (now named Amp) get along with a female cat. Saiki tries to play an unpopular but cheap video game, and realizes how crappy it is. Kaido’s mother invites Nendo and Saiki to their home.|
|6||September 4, 2013 ||ISBN 978-4-08-870806-5|
|Reita tries to confess to a girl he likes by letting the spirits of popular guys possess his body. A young boy named Yuuta Iridatsu believes Saiki to be his favorite superhero Cyborg Cider-Man Version 2 after witnessing his abilities. Chiyo and Kokomi get to know each other, but suspect they both share a crush on Saiki. The two girls try to join Saiki’s group for the class trip to Okinawa. Saiki intervenes on some obstacles that threaten to cancel or ruin the class trip. Kaido tries to show off his Kansai dialect , and the guys visit a snake vs. mongoose show. After stopping the guys from peeping at the girls in the bath, Saiki rests outside until Kokomi arrives and removes one of his hairpins, and then the hotel disappears. After restoring the hotel, Saiki finds himself having to deal with Kokomi who thinks she is in a lucid dream with him. The next day the class visits a pineapple farm and aquarium, and then the beach where Chiyo gets upset that she doesn’t garner any attention from the guys. However, when some guys hit on Teruhashi and disparage Chiyo, Kaido sticks up for her. On the last day of the trip, Saiki attempts to get a limited coffee red bean anmitsu . Saiki visits his father’s workplace which is a manga publishing company.|
|7||December 4, 2013 ||ISBN 978-4-08-870853-9|
|Yuuta visits Saiki and learns that Nendo looks like Baron Cola. Saiki’s visit to the local festival is disrupted by a pickpocket . Transfer student Aren Kuboyasu finds it difficult to hold back from his habits as a delinquent, especially when it comes to interacting with Saiki and his friends. Nendo’s father sees her former wife and falls in love; Saiki tries to help him possess Nendo. The cafe manager ponders how to attract new customers. Saiki’s class tries to determine what project to do for the upcoming school festival. Toritsuka asks Saiki to help him with his band. During the festival, the guys visit a haunted house. But when Saiki takes off his glasses, he accidentally gazes at Nendo, turning him into stone . Saiki must prevent from the statue from breaking the second time. The results of the popularity poll are presented.|
|8||April 4, 2014 ||ISBN 978-4-08-880027-1|
|Kaido, Nendo, and Saiki get lost trying to find the class after party. Saiki uses the Straw Millionaire concept to exchange things of slightly increasing value so he can pay for his restaurant bill. In order to avoid Makoto’s drama shoot, Saiki takes Kokomi on a date in the neighboring town. But when Makoto changes locations to that town, Saiki takes Kokomi to a game center and tries to find ways to get Kokomi to get her to dislike him. Kaido acts like a detective drama character to try to solve a mystery at school. Toritsuka tries to go on a big date with all the girls he has attracted from letting ghosts possess his body. Saiki dresses up as Santa Claus to deliver gifts for the neighborhood kids. Saiki tries to buy a television with his New Year’s money but is pestered by the store clerk. Saiki’s classmates talk about their New Year’s firsts. Kaido sees Kuboyasu hold off some bullies and suspects he is a delinquent. Kaido and Saiki are later bullied for money when Kuboyasu intervenes.|
|9||July 4, 2014 ||ISBN 978-4-08-880072-1|
|After Nendo is fired from his part-time jobs, Kaido and Kuboyasu try to help him on the next one. Saiki’s class does a 10km run. Kokomi visits Saiki’s mom but has to deal with Saiki babysitting Yuuta. After watching a good movie, Saiki visits the film location but finds that the actual acting was quite different. Amp swallows a part of Saiki’s dad’s model robot figure, so Saiki transforms his size to retrieve it, but has to deal with a cockroach. Saiki has trouble trying to get and enjoy a parfait at his class karaoke party. Kongo is a delinquent third-year student bully at PK Academy, but will be held back a grade unless he changes his ways. The Saikis visit Kusuo’s grandparents, of whom his grandfather Kumagoro is a classic tsundere (cold on the outside, warm on the inside). They go to a run-down amusement park where Kumagoro tries to bond with Kusuo. Kumagoro plots for them to stay longer, but when they come across a road black, Kusuo reveals to his grandparents that he is a psychic. Saiki and friends try out a new cross-over fighting video game.|
|10||September 4, 2014 ||ISBN 978-4-08-880175-9|
|Toritsuka recruits Saiki to join his Occult Club. Saiki looks forward to making crepes , but is grouped with Hairo and Kaido, who know nothing about cooking. Saiki suspects his class is planning a surprise birthday party for him but it is actually his father’s, so he has him attend in his place. Saiki hears the number 100 in multiple places. Saiki is abducted and put on trial by Kokomi’s fan club, the Kokomins, for being too close to Kokomi. Trying to avoid the guys, Saiki accidentally ends up in the girls’ locker room. When Saiki’s hair ornament gets damaged, his family has to get it repaired by Saiki’s older brother Kusuke who is in London. After repairing the ornament, Kusuke challenges Kusuo to a game of tag in which Kusuo has to evade Kusuke for three hours but bring Nendo and Kaido along.|
|11||December 4, 2014 ||ISBN 978-4-08-880224-4|
|Saiki, Nendo and Kaido visit a modern art museum where Kaido starts acting like some kind of expert. Saiki wants to have a trouble-free summer vacation, but his friends soon book up his entire summer with activities. He joins the Occult Club’s summer trip where they have a test of courage with Kaido, Chiyo, Arisa, and Toritsuka. He and Nendo then join Hairo’s Tennis Club training camp. Saiki and Nendo join Mera in a clinical trials where they take mysterious drugs. Saiki notices Mera and Nendo transform grotesquely. Saiki, Kaido, and Kuboyasu then attend motorcycle training classes. Saiki then takes Teruhashi on a date to the amusement park but brings Yuuta, and they have to watch a hero show. The wealthy Metori Saiko transfers into Saiki’s class and woos Kokomi, but she refuses because she harbors feelings for Saiki. Saiko then makes life miserable for Saiki and Kokomi’s friends and family, so Saiki gets his revenge on Saiko. When Saiki’s grandparents visit Tokyo, Kumagoro is left in the Shibuya district by himself and ends up befriending Nendo. Saiki visits Chono and Michael, who have become more successful as comedy magicians.|
|12||February 4, 2015 ||ISBN 978-4-08-880304-3|
|At a video rental store , Saiki has the challenge of picking a film that won’t get spoiled by the clerk’s thoughts. Saiko offers to pay Nendo to be his underling , but Nendo refuses, preferring to just be friends. Kaido hosts a Halloween party , but the guys have no clue how to dress or what to do there. Saiki is interrupted by his friends during the break in-between class periods. Toritsuka asks Saiki to help him impress a girl named Aiko by joining Hairo’s tennis team training. Chiyo has become morbidly obese , so Saiki uses telepathy to project Kaido’s image to motivate her to exercise to lose the weight. Saiki’s parents celebrate their 19th wedding anniversary when Kusuke calls and informs them that Saiki’s limiter might have a problem. When Saiki awakens, he finds himself 20 years in the past and must stop Nendo’s father from ruining his parents’ first encounter. Although he gets his parents to meet, but when he returns to the present, things have adically changed due to the butterfly effect to a post-apocalyptic world . Saiki finds that Kusuke had been using a time machine and started World War 3 . In a cross-over chapter , Saiki and his father visit the diner from Food Wars!: Shokugeki no Soma . Saiki, Kaido and Nendo are shopping at a clothing store when they see Kokomi and attempt some questionably fashionable clothes. Kuboyasu, who has been dealing with a lot of challenge letters, receives a love letter for once and doesn’t know how to respond.|
|13||May 1, 2015 ||ISBN 978-4-08-880355-5|
|Hoping for some peace and quiet, Saiki hangs out on a playground, but feels uneasy when Nendo, Kaido, and Kokomi have a Christmas party at his house. On New Year’s, Saiki notices his friends and family are showing up on various television programs. Saiki transforms into a girl in order to visit a dessert cafe but runs into Kokomi, Chiyo, and Mera. When Nendo and Kaido visit Saiki to play in the snow, Saiki gets premonitions of the two in a tragic situation. Saiki follows his mother to a class reunion where he foils her former classmate’s revenge plan. Kaido and Kuboyasu speculate that Hairo might be gay. Saiki helps a lost hamster find his owners, but as they bought another hamster, he asks his classmates to take care of him. When Saiki and the guys have to give Saiko some school printouts, Saiko tries to show off his mansion to them, but they are not impressed. Saiko has the house radically remodeled with things the guys like. Saiki takes his father’s place at work and visits a manga artist to get him to finish his chapter.|
|14||August 4, 2015 ||ISBN 978-4-08-880426-2|
|During the graduation ceremony, Saiki realizes he hardly knows any upperclassmen unlike his friends. Kaido’s April Fool’s Day jokes bite back when he sees some of Saiki’s telekinesis activity and cannot convince his classmates it is real. Toritsuka asks Saiki to help him exorcise a ghost in the music room. Imu Rifuta, an attractive first-year girl, finds that she is no match for Teruhashi. Saiki finds that his sneezing from allergies has a serious impact. Saiki and friends participate in a trash cleanup competition. Saiki’s parents prepare birthday gifts for each other. Nendo and Kaido bring Saiki to the circus, but Chono, who had been working as a clown magician, gets injured so Saiki has to perform in his place. But when Saiki gets a premonition of a big accident, he finds himself more involved in the acts in order to stop it. Rifuta notices that Teruhashi pays attention to Saiki and tries to woo him. After getting a massage chair from Kusuke, Kurumi gives Kusuo a massage but finds his shoulders to be unusally stiff.|
|15||October 3, 2015 ||ISBN 978-4-08-880462-0|
|Saiko invites the gang on a cruise, but they get shipwrecked on an island. Saiki realizes that things got out of control because his limiter was removed, and that they are now far away from Japan. He helps the gang build a raft by making materials conveniently available. They argue over who should stay or go. Saiki secretly arranges for them to be rescued. After returning to school, the newspaper club tries to interview them and portray their activities in a sensationalist light, but Saiki foils their plan. Saiki finds himself, Nendo and Kaido stuck in a time loop . Saiki’s father tells him to play his online game. Saiki’ grandfather is scammed into bringing money to a station, but the scammer is actually Kusuke. The Saikis hang out with the grandparents and attend a festival. The bonus chapter is about Kokomi’s story about pursuing Saiki.|
|16||January 4, 2016 ||ISBN 978-4-08-880582-5|
|17||April 4, 2016 ||ISBN 978-4-08-880652-5|
|18||July 4, 2016 ||ISBN 978-4-08-880728-7|
|19||October 4, 2016 ||ISBN 978-4-08-880791-1|
|20||December 31, 2016 ||ISBN 978-4-08-880887-1|
|21||April 4, 2017 ||ISBN 978-4-08-881047-8|
|22||July 4, 2017 ||ISBN 978-4-08-881180-2|
|23||October 4, 2017 ||ISBN 978-4-08-881211-3|
|24||January 4, 2018 ||ISBN 978-4-08-881315-8|
|25||April 4, 2018 ||ISBN 978-4-08-881377-6|
|26||August 3, 2018 ||ISBN 978-4-08-881539-8|
Light Novel[ edit ]
On May 4, 2013, a light novel titled, Saiki Kusuo no Psi-nan – Extra Story of Psychics was released, following with Saiki Kusuo no Psi-nan – Extra Story of Psychics 2 in July 2014.
Anime[ edit ]
A flash anime series based on the manga began release on Jump Live from August 4, 2013, featuring the same voice cast as an earlier Comic adaptation. 
An anime television adaptation was announced in the Weekly Shōnen Jump magazine’s 23rd issue of 2016. J.C.Staff and Egg Firm are producing the adaptation, with Hiroaki Sakurai directing, Michiko Yokote handling series composition and Masayuki Onji designing the characters.  The series began airing on July 4, 2016 on TV Tokyo , with an episode airing every weekday morning followed by a compilation episode at the end of each week, the series will contain one hundred and twenty episodes in total, along with twenty four compilation episodes on Oha Suta .  The opening themes are “Seishun wa Zankoku janai” (青春は残酷じゃない Youth Isn’t So Cruel) by Natsuki Hanae , “Sai-Sai-Saikōchō!” (最Ψ最好調！ The Most Favorable!) by Denpagumi.inc from the thirteenth compiled episode onwards and “Saihakkenden!” (Ψ発見伝！) by Denpagumi.inc from second season, while the ending theme, also used for the short episodes, is “Psi desu – I Like You” (Ψです I LIKE YOU) by Denpagumi.inc . From the thirteenth compiled episode onwards, the ending theme is “Kokoro” (こころ Heart) by Hanae. From second season, the ending theme is “Saihakkenden!” (Ψ発見伝！) by Denpagumi.inc. The series was simulcast by Funimation , who released an English dub starting from August 7, 2016.  
A second season premiered on January 17, 2018. 
In the last episode of second season it was revealed that a third season is in the works and will presumably be aired in Fall 2018 or early 2019. 
Video games[ edit ]
A video game titled Saiki Kusuo no Psi Nan: Shijō Psi Dai no Psi Nan!? was announced in the Weekly Shōnen Jump magazine’s 32nd issue of 2016. The game was developed by Bandai Namco Studios and published by Bandai Namco Entertainment for the Nintendo 3DS handheld game console.  It was released on November 10, 2016 in Japan. 
Another video game adaptation, 斉木楠雄のΨ難 妄想暴走！Ψキックバトル, is a tower defense game for mobile phones announced at Jump Festa 2018.  It was released on April 16, 2018 in Japan. 
Kusuo also appears as a playable character in the Jump crossover fighting game J-Stars Victory VS released in 2014.  Its European and North American release marks the first release of Saiki Kusuo no Psi-nan material outside Japan.
Live-action film[ edit ]
Notes[ edit ]
- ^ The author notes that he too is terrified of cockroaches. Vol. 7 author’s note
Works cited[ edit ]
- ^ “Ch.” is shortened form for chapter and refers to a chapter number of The Disastrous Life of Saiki K. manga. Chapters preceded with a P refer to the one-shots that were later collected in Volume 0.
- ^ “Ep.” is shortened form for episode and refers to an episode number of The Disastrous Life of Saiki K. anime
References[ edit ]
- ^ “The Disastrous Life of Saiki K Part 1 Blu-Ray/DVD” . Right Stuf Inc. Retrieved January 20, 2018.
- ^ “山崎賢人が「斉木楠雄のΨ難」で主演、監督は「銀魂」も手がける福田雄一” . 映画ナタリー. 2016-08-01. Retrieved 2016-08-01.
- ^ a b c “Saiki Kusuo no Psi-nan VOMIC official website” . Shueisha (in Japanese). Archived from the original on 2013-10-06. Retrieved 2015-01-17.
- ^ a b c d e f “Saiki Kusuo no Psi Nan Manga Gets TV Anime in July” . Anime News Network . May 2, 2016. Retrieved May 2, 2016.
- ^ a b c d e f g h i j “Funimation Reveals Dub Casts for Planetarian, Handa-kun, Saiki K., Show By Rock!! Short!!” . Anime News Network. August 1, 2016. Retrieved January 13, 2017.
- ^ http://www.crunchyroll.com/anime-news/2016/09/26/koichi-yamadera-and-rie-tanaka-join-cast-of-the-disastrous-life-of-saiki-k
- ^ “The Disastrous Life of Saiki K. Anime Casts Kenji Nojima, Masaya Matsukaze” . Anime News Network. October 7, 2016. Retrieved October 9, 2016.
- ^ a b c d “Saiki Kusuo no Psi Nan Adds Yoshimasa Hosoya, Maaya Uchida, Tomoaki Maeno, Showtaro Morikubo” . Anime News Network. June 19, 2016. Retrieved June 19, 2016.
- ^ “M.A.O Joins The Disastrous Life of Saiki K. 2nd Season’s Cast as Imu Rifuta” . Anime News Network. November 26, 2017. Retrieved December 10, 2017.
- ^ a b c “Eri Kitamura Joins The Disasterous Life of Saiki K. 2nd Season’s Cast as Mikoto Aiura” . Anime News Network. Retrieved November 20, 2017.
- ^ https://manga.tokyo/news/the-disastrous-life-of-saiki-k-introduces-mikoto-aiura/
- ^ 斉木楠雄のサイ難 25(ジャンプコミックス) (in Japanese). Shueisha.
- ^ a b “The Disastrous Life of Saiki K. Manga Ends, Gets 4-Panel Manga Sequel” . Anime News Network. February 25, 2018. Retrieved February 25, 2018.
- ^ 超能力者 斉木楠雄のサイ難 0 (in Japanese). Shueisha. Retrieved November 22, 2016.
- ^ 斉木楠雄のサイ難 1 (in Japanese). Shueisha. Retrieved November 22, 2016.
- ^ 斉木楠雄のサイ難 2 (in Japanese). Shueisha. Retrieved November 22, 2016.
- ^ 斉木楠雄のサイ難 3 (in Japanese). Shueisha. Retrieved November 22, 2016.
- ^ 斉木楠雄のサイ難 4 (in Japanese). Shueisha. Retrieved November 22, 2016.
- ^ 斉木楠雄のサイ難 5 (in Japanese). Shueisha. Retrieved November 22, 2016.
- ^ 斉木楠雄のサイ難 6 (in Japanese). Shueisha. Retrieved November 22, 2016.
- ^ 斉木楠雄のサイ難 7 (in Japanese). Shueisha. Retrieved November 22, 2016.
- ^ 斉木楠雄のサイ難 8 (in Japanese). Shueisha. Retrieved November 22, 2016.
- ^ 斉木楠雄のサイ難 9 (in Japanese). Shueisha. Retrieved November 22, 2016.
- ^ 斉木楠雄のサイ難 10 (in Japanese). Shueisha. Retrieved November 22, 2016.
- ^ 斉木楠雄のサイ難 11 (in Japanese). Shueisha. Retrieved November 22, 2016.
- ^ 斉木楠雄のサイ難 12 (in Japanese). Shueisha. Retrieved November 22, 2016.
- ^ 斉木楠雄のサイ難 13 (in Japanese). Shueisha. Retrieved November 22, 2016.
- ^ 斉木楠雄のサイ難 14 (in Japanese). Shueisha. Retrieved November 22, 2016.
- ^ 斉木楠雄のサイ難 15 (in Japanese). Shueisha. Retrieved November 22, 2016.
- ^ 斉木楠雄のサイ難 16 (in Japanese). Shueisha. Retrieved November 22, 2016.
- ^ 斉木楠雄のサイ難 17 (in Japanese). Shueisha. Retrieved November 22, 2016.
- ^ 斉木楠雄のサイ難 18 (in Japanese). Shueisha. Retrieved November 22, 2016.
- ^ 斉木楠雄のサイ難 19 (in Japanese). Shueisha. Retrieved November 22, 2016.
- ^ 斉木楠雄のサイ難 20 (in Japanese). Shueisha. Retrieved November 22, 2016.
- ^ 斉木楠雄のサイ難 21 (in Japanese). Shueisha. Retrieved March 7, 2017.
- ^ 斉木楠雄のサイ難 22 (in Japanese). Shueisha. Retrieved June 19, 2017.
- ^ 斉木楠雄のサイ難 23 (in Japanese). Shueisha. Retrieved June 19, 2017.
- ^ 斉木楠雄のサイ難 24 (in Japanese). Shueisha. Retrieved December 11, 2017.
- ^ 斉木楠雄のサイ難 25 (in Japanese). Shueisha. Retrieved February 26, 2018.
- ^ 斉木楠雄のサイ難 26 (in Japanese). Shueisha. Retrieved July 13, 2018.
- ^ “Saiki Kusuo no Psi Nan Manga’s Adaptation Is a Flash Anime” . Anime News Network .
- ^ “Saiki Kusuo no Psi Nan Anime’s Main Visual, Premiere Dates Revealed” . Anime News Network . May 30, 2016. Retrieved May 30, 2016.
- ^ “Funimation to Stream Cheer Boys!!, The Disastrous Life of Saiki K., Puzzle & Dragons X” . Anime News Network . June 29, 2016. Retrieved July 11, 2016.
- ^ “The Disastrous Life of Saiki K. Season 2 Listed With 24 Episodes” . Anime News Network. Retrieved 21 January 2018.
- ^ https://www.monstersandcritics.com/anime/the-disastrous-life-of-saiki-k-season-3-release-date-anime-sequel-teased-u-s-netflix-releases-saiki-kusuo-no-psi-nan-season-2-english-dub-and-episodes-13-through-24-later-in-2018/
- ^ “The Disastrous Life of Saiki K. Gets 3DS Game” . Anime News Network . July 10, 2016. Retrieved July 10, 2016.
- ^ Sato. “Saiki Kusuo no Psy-nan’s 3DS Game Releases In Japan On November 10, 2016” . Siliconera. Retrieved 16 April 2018.
- ^ Sherman, Jennifer. “The Disastrous Life of Saiki K. Gets Smartphone Game” . Anime News Network . Retrieved 16 April 2018.
- ^ “Teaser Page” . Saiki K. App Website. Retrieved 16 April 2018.
- ^ “J-Stars Victory Vs. Game’s 52 Characters Unveiled” . Anime News Network .
External links[ edit ]
- Official website (in Japanese)
- The Disastrous Life of Saiki K. (manga) at Anime News Network ‘s encyclopedia
- Manga series
- 2012 manga
- 2016 anime television series
- 2018 manga
- 2018 anime television series
- Anime series based on manga
- Bandai Namco games
- Comedy anime and manga
- Japan-exclusive video games
- Mobile games
- Nintendo 3DS games
- Nintendo 3DS-only games
- Science fiction anime and manga
- Shōnen manga
- Shueisha manga
- TV Tokyo shows
- Video games based on anime and manga
- Japanese high school television series
- Psychic powers in fiction
- Video games developed in Japan
- CS1 Japanese-language sources (ja)
- CS1 uses Japanese-language script (ja)
- Articles with short description
- Articles containing Japanese-language text
- Articles with Japanese-language external links
- This page was last edited on 24 August 2018, at 18:32 (UTC).
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IEEE 754-1985 was an industry standard for representing floating-point numbers in computers , officially adopted in 1985 and superseded in 2008 by IEEE 754-2008 . During its 23 years, it was the most widely used format for floating-point computation. It was implemented in software, in the form of floating-point libraries , and in hardware, in the instructions of many CPUs and FPUs . The first integrated circuit to implement the draft of what was to become IEEE 754-1985 was the Intel 8087 .
IEEE 754-1985 represents numbers in binary , providing definitions for four levels of precision, of which the two most commonly used are:
|Level||Width||Range at full precision||Precision [a]|
|Single precision||32 bits||±1.18×10−38 to ±3.4×1038||Approximately 7 decimal digits|
|Double precision||64 bits||±2.23×10−308 to ±1.80×10308||Approximately 16 decimal digits|
The standard also defines representations for positive and negative infinity , a ” negative zero “, five exceptions to handle invalid results like division by zero , special values called NaNs for representing those exceptions, denormal numbers to represent numbers smaller than shown above, and four rounding modes.
- 1 Representation of numbers
- 1.1 Zero
- 1.2 Denormalized numbers
- 2 Representation of non-numbers
- 2.1 Positive and negative infinity
- 2.2 NaN
- 3 Range and precision
- 3.1 Single precision
- 3.2 Double precision
- 3.3 Extended formats
- 4 Examples
- 5 Comparing floating-point numbers
- 6 Rounding floating-point numbers
- 7 Extending the real numbers
- 8 Functions and predicates
- 8.1 Standard operations
- 8.2 Recommended functions and predicates
- 9 History
- 10 See also
- 11 Notes
- 12 References
- 13 Further reading
- 14 External links
Representation of numbers[ edit ]
Floating-point numbers in IEEE 754 format consist of three fields: a sign bit , a biased exponent , and a fraction. The following example illustrates the meaning of each.
The decimal number 0.1562510 represented in binary is 0.001012 (that is, 1/8 + 1/32). (Subscripts indicate the number base .) Analogous to scientific notation , where numbers are written to have a single non-zero digit to the left of the decimal point, we rewrite this number so it has a single 1 bit to the left of the “binary point”. We simply multiply by the appropriate power of 2 to compensate for shifting the bits left by three positions:
Now we can read off the fraction and the exponent: the fraction is .012 and the exponent is −3.
As illustrated in the pictures, the three fields in the IEEE 754 representation of this number are:
- sign = 0, because the number is positive. (1 indicates negative.)
- biased exponent = −3 + the “bias”. In single precision, the bias is 127, so in this example the biased exponent is 124; in double precision, the bias is 1023, so the biased exponent in this example is 1020.
- fraction = .01000…2.
IEEE 754 adds a bias to the exponent so that numbers can in many cases be compared conveniently by the same hardware that compares signed 2’s-complement integers. Using a biased exponent, the lesser of two positive floating-point numbers will come out “less than” the greater following the same ordering as for sign and magnitude integers. If two floating-point numbers have different signs, the sign-and-magnitude comparison also works with biased exponents. However, if both biased-exponent floating-point numbers are negative, then the ordering must be reversed. If the exponent were represented as, say, a 2’s-complement number, comparison to see which of two numbers is greater would not be as convenient.
The leading 1 bit is omitted since all numbers except zero start with a leading 1; the leading 1 is implicit and doesn’t actually need to be stored which gives an extra bit of precision for “free.”
Zero[ edit ]
The number zero is represented specially:
- sign = 0 for positive zero , 1 for negative zero .
- biased exponent = 0.
- fraction = 0.
Denormalized numbers[ edit ]
The number representations described above are called normalized, meaning that the implicit leading binary digit is a 1. To reduce the loss of precision when an underflow occurs, IEEE 754 includes the ability to represent fractions smaller than are possible in the normalized representation, by making the implicit leading digit a 0. Such numbers are called denormal . They don’t include as many significant digits as a normalized number, but they enable a gradual loss of precision when the result of an arithmetic operation is not exactly zero but is too close to zero to be represented by a normalized number.
A denormal number is represented with a biased exponent of all 0 bits, which represents an exponent of −126 in single precision (not −127), or −1022 in double precision (not −1023).  In contrast, the smallest biased exponent representing a normal number is 1 (see examples below).
Representation of non-numbers[ edit ]
The biased-exponent field is filled with all 1 bits to indicate either infinity or an invalid result of a computation.
Positive and negative infinity[ edit ]
Positive and negative infinity are represented thus:
- sign = 0 for positive infinity, 1 for negative infinity.
- biased exponent = all 1 bits.
- fraction = all 0 bits.
NaN[ edit ]
Some operations of floating-point arithmetic are invalid, such as taking the square root of a negative number. The act of reaching an invalid result is called a floating-point exception. An exceptional result is represented by a special code called a NaN, for ” Not a Number “. All NaNs in IEEE 754-1985 have this format:
- sign = either 0 or 1.
- biased exponent = all 1 bits.
- fraction = anything except all 0 bits (since all 0 bits represents infinity).
Range and precision[ edit ]
Relative precision of single (binary32) and double precision (binary64) numbers, compared with decimal representations using a fixed number of significant digits . Relative precision is defined here as ulp(x)/x, where ulp(x) is the unit in the last place in the representation of x, i.e. the gap between x and the next representable number.
Precision is defined as the minimum difference between two successive mantissa representations; thus it is a function only in the mantissa; while the gap is defined as the difference between two successive numbers. 
Single precision[ edit ]
Single-precision numbers occupy 32 bits. In single precision:
- The positive and negative numbers closest to zero (represented by the denormalized value with all 0s in the exponent field and the binary value 1 in the fraction field) are
- ±2−149 ≈ ±1.40130×10−45
- The positive and negative normalized numbers closest to zero (represented with the binary value 1 in the exponent field and 0 in the fraction field) are
- ±2−126 ≈ ±1.17549×10−38
- The finite positive and finite negative numbers furthest from zero (represented by the value with 254 in the exponent field and all 1s in the fraction field) are
- ±(1−2−24) × 2128  ≈ ±3.40282×1038
Some example range and gap values for given exponents in single precision:
|Actual Exponent (unbiased)||Exp (biased)||Minimum||Maximum||Gap|
|0||127||1||≈ 1.999999880791||≈ 1.19209e-7|
|1||128||2||≈ 3.999999761581||≈ 2.38419e-7|
|2||129||4||≈ 7.999999523163||≈ 4.76837e-7|
|10||137||1024||≈ 2047.999877930||≈ 1.22070e-4|
|11||138||2048||≈ 4095.999755859||≈ 2.44141e-4|
|127||254||≈ 1.70141e38||≈ 3.40282e38||≈ 2.02824e31|
As an example, 16,777,217 can not be encoded as a 32-bit float as it will be rounded to 16,777,216. This shows why floating point arithmetic is unsuitable for accounting software. However, all integers within the representable range that are a power of 2 can be stored in a 32-bit float without rounding.
Double precision[ edit ]
Double-precision numbers occupy 64 bits. In double precision:
- The positive and negative numbers closest to zero (represented by the denormalized value with all 0s in the Exp field and the binary value 1 in the Fraction field) are
- ±2−1074 ≈ ±4.94066×10−324
- The positive and negative normalized numbers closest to zero (represented with the binary value 1 in the Exp field and 0 in the fraction field) are
- ±2−1022 ≈ ±2.22507×10−308
- The finite positive and finite negative numbers furthest from zero (represented by the value with 2046 in the Exp field and all 1s in the fraction field) are
- ±(1−2−53) × 21024  ≈ ±1.79769×10308
Some example range and gap values for given exponents in double precision:
|Actual Exponent (unbiased)||Exp (biased)||Minimum||Maximum||Gap|
|0||1023||1||≈ 1.999999999999999777955||≈ 2.22045e-16|
|1||1024||2||≈ 3.999999999999999555911||≈ 4.44089e-16|
|2||1025||4||≈ 7.999999999999999111822||≈ 8.88178e-16|
|10||1033||1024||≈ 2047.999999999999772626||≈ 2.27374e-13|
|11||1034||2048||≈ 4095.999999999999545253||≈ 4.54747e-13|
|1023||2046||≈ 8.98847e307||≈ 1.79769e308||≈ 1.99584e292|
Extended formats[ edit ]
The standard also recommends extended format(s) to be used to perform internal computations at a higher precision than that required for the final result, to minimise round-off errors: the standard only specifies minimum precision and exponent requirements for such formats. The x87 80-bit extended format is the most commonly implemented extended format that meets these requirements.
Examples[ edit ]
Here are some examples of single-precision IEEE 754 representations:
|Type||Sign||Actual Exponent||Exp (biased)||Exponent field||Significand (fraction field)||Value|
|Zero||0||−127||0||0000 0000||000 0000 0000 0000 0000 0000||0.0|
|Negative zero||1||−127||0||0000 0000||000 0000 0000 0000 0000 0000||−0.0|
|One||0||0||127||0111 1111||000 0000 0000 0000 0000 0000||1.0|
|Minus One||1||0||127||0111 1111||000 0000 0000 0000 0000 0000||−1.0|
|Smallest denormalized number||*||−126||0||0000 0000||000 0000 0000 0000 0000 0001||±2−23 × 2−126 = ±2−149 ≈ ±1.4×10−45|
|“Middle” denormalized number||*||−126||0||0000 0000||100 0000 0000 0000 0000 0000||±2−1 × 2−126 = ±2−127 ≈ ±5.88×10−39|
|Largest denormalized number||*||−126||0||0000 0000||111 1111 1111 1111 1111 1111||±(1−2−23) × 2−126 ≈ ±1.18×10−38|
|Smallest normalized number||*||−126||1||0000 0001||000 0000 0000 0000 0000 0000||±2−126 ≈ ±1.18×10−38|
|Largest normalized number||*||127||254||1111 1110||111 1111 1111 1111 1111 1111||±(2−2−23) × 2127 ≈ ±3.4×1038|
|Positive infinity||0||128||255||1111 1111||000 0000 0000 0000 0000 0000||+∞|
|Negative infinity||1||128||255||1111 1111||000 0000 0000 0000 0000 0000||−∞|
|Not a number||*||128||255||1111 1111||non zero||NaN|
|* Sign bit can be either 0 or 1 .|
Comparing floating-point numbers[ edit ]
Every possible bit combination is either a NaN or a number with a unique value in the affinely extended real number system with its associated order, except for the two bit combinations negative zero and positive zero, which sometimes require special attention (see below). The binary representation has the special property that, excluding NaNs, any two numbers can be compared as sign and magnitude integers ( endianness issues apply). When comparing as 2’s-complement integers: If the sign bits differ, the negative number precedes the positive number, so 2’s complement gives the correct result (except that negative zero and positive zero should be considered equal). If both values are positive, the 2’s complement comparison again gives the correct result. Otherwise (two negative numbers), the correct FP ordering is the opposite of the 2’s complement ordering.
Rounding errors inherent in floating point calculations often make comparison of results for exact equality not useful. Choosing an acceptable range is a complex topic.
Although negative zero and positive zero are generally considered equal for comparison purposes, some programming language relational operators and similar constructs might or do treat them as distinct. According to the Java Language Specification,  comparison and equality operators treat them as equal, but
Math.max() distinguish them (officially starting with Java version 1.1 but actually with 1.1.1), as do the comparison methods
compareTo() and even
compare() of classes
Rounding floating-point numbers[ edit ]
The IEEE standard has four different rounding modes; the first is the default; the others are called directed roundings .
- Round to Nearest – rounds to the nearest value; if the number falls midway it is rounded to the nearest value with an even (zero) least significant bit, which occurs 50% of the time (in IEEE 754-2008 this mode is called roundTiesToEven to distinguish it from another round-to-nearest mode)
- Round toward 0 – directed rounding towards zero
- Round toward +∞ – directed rounding towards positive infinity
- Round toward −∞ – directed rounding towards negative infinity.
Extending the real numbers[ edit ]
The IEEE standard employs (and extends) the affinely extended real number system , with separate positive and negative infinities. During drafting, there was a proposal for the standard to incorporate the projectively extended real number system , with a single unsigned infinity, by providing programmers with a mode selection option. In the interest of reducing the complexity of the final standard, the projective mode was dropped, however. The Intel 8087 and Intel 80287 floating point co-processors both support this projective mode.   
Functions and predicates[ edit ]
Standard operations[ edit ]
The following functions must be provided:
- Add, subtract, multiply, divide
- Square root
- Floating point remainder. This is not like a normal modulo operation , it can be negative for two positive numbers. It returns the exact value of x–(round(x/y)·y).
- Round to nearest integer . For undirected rounding when halfway between two integers the even integer is chosen.
- Comparison operations. Besides the more obvious results, IEEE 754 defines that −∞ = −∞, +∞ = +∞ and x ≠
NaNfor any x (including
Recommended functions and predicates[ edit ]
copysign(x,y)returns x with the sign of y, so
copysign(x,1.0). This is one of the few operations which operates on a NaN in a way resembling arithmetic. The function
copysignis new in the C99 standard.
- −x returns x with the sign reversed. This is different from 0−x in some cases, notably when x is 0. So −(0) is −0, but the sign of 0−0 depends on the rounding mode.
finite(x)a predicate for “x is a finite value”, equivalent to −Inf < x < Inf
isnan(x)a predicate for “x is a NaN”, equivalent to “x ≠ x”
x <> ywhich turns out to have different exception behavior than NOT(x = y).
unordered(x, y)is true when “x is unordered with y”, i.e., either x or y is a NaN.
nextafter(x,y)returns the next representable value from x in the direction towards y
History[ edit ]
In 1976 Intel began planning to produce a floating point coprocessor. John Palmer, the manager of the effort, persuaded them that they should try to develop a standard for all their floating point operations. William Kahan was hired as a consultant; he had helped improve the accuracy of Hewlett-Packard ‘s calculators. Kahan initially recommended that the floating point base be decimal  but the hardware design of the coprocessor was too far along to make that change.
The work within Intel worried other vendors, who set up a standardization effort to ensure a ‘level playing field’. Kahan attended the second IEEE 754 standards working group meeting, held in November 1977. Here, he received permission from Intel to put forward a draft proposal based on the standard arithmetic part of their design for a coprocessor. The arguments over gradual underflow lasted until 1981 when an expert hired by DEC to assess it sided against the dissenters.
Even before it was approved, the draft standard had been implemented by a number of manufacturers.   The Intel 8087 , which was announced in 1980, was the first chip to implement the draft standard.
See also[ edit ]
- −0 (negative zero)
- Intel 8087
- minifloat for simple examples of properties of IEEE 754 floating point numbers
- Fixed-point arithmetic
Notes[ edit ]
- ^ Precision: The number of decimal digits precision is calculated via number_of_mantissa_bits * Log10(2). Thus ~7.2 and ~15.9 for single and double precision respectively.
References[ edit ]
- ^ Hennessy. Computer Organization and Design. Morgan Kaufmann. p. 270.
- ^ Hossam A. H. Fahmy; Shlomo Waser; Michael J. Flynn, Computer Arithmetic (PDF), archived from the original (PDF) on 2010-10-08, retrieved 2011-01-02
- ^ a b William Kahan . “Lecture Notes on the Status of IEEE 754” (PDF). October 1, 1997 3:36 am. Elect. Eng. & Computer Science University of California. Retrieved 2007-04-12.
- ^ “Java Language and Virtual Machine Specifications” . Java Documentation.
- ^ John R. Hauser (March 1996). “Handling Floating-Point Exceptions in Numeric Programs” (PDF). ACM Transactions on Programming Languages and Systems. 18 (2): 139–174. doi : 10.1145/227699.227701 .
- ^ David Stevenson (March 1981). “IEEE Task P754: A proposed standard for binary floating-point arithmetic”. IEEE Computer. 14 (3): 51–62.
- ^ William Kahan and John Palmer (1979). “On a proposed floating-point standard”. SIGNUM Newsletter. 14 (Special): 13–21. doi : 10.1145/1057520.1057522 .
- ^ W. Kahan 2003, pers. comm. to Mike Cowlishaw and others after an IEEE 754 meeting[ unreliable source? ]
- ^ Charles Severance (20 February 1998). “An Interview with the Old Man of Floating-Point” .
- ^ Charles Severance . “History of IEEE Floating-Point Format” . Connexions.
Further reading[ edit ]
- Charles Severance (March 1998). “IEEE 754: An Interview with William Kahan” (PDF). IEEE Computer . 31 (3): 114–115. doi : 10.1109/MC.1998.660194 . Retrieved 2008-04-28.
- David Goldberg (March 1991). “What Every Computer Scientist Should Know About Floating-Point Arithmetic” (PDF). ACM Computing Surveys . 23 (1): 5–48. doi : 10.1145/103162.103163 . Retrieved 2008-04-28.
- Chris Hecker (February 1996). “Let’s Get To The (Floating) Point” (PDF). Game Developer Magazine: 19–24. ISSN 1073-922X .
- David Monniaux (May 2008). “The pitfalls of verifying floating-point computations” . ACM Transactions on Programming Languages and Systems . 30 (3): article #12. arXiv : cs/0701192 . doi : 10.1145/1353445.1353446 . ISSN 0164-0925 .: A compendium of non-intuitive behaviours of floating-point on popular architectures, with implications for program verification and testing.
External links[ edit ]
- Comparing floats
- Coprocessor.info: x87 FPU pictures, development and manufacturer information
- IEEE 854-1987 — History and minutes
- IEEE754 (Single and Double precision) Online Converter
- Computer arithmetic
- IEEE standards
- Floating point
- All articles lacking reliable references
- Articles lacking reliable references from October 2016
- This page was last edited on 16 May 2018, at 12:14 (UTC).
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- 1 EMMAX Overview
- 2 Download EMMAX
- 3 Key Instructions
- 3.1 Preparing Input Genotype Files
- 3.2 Preparing Input Phenotype Files
- 3.3 Creating Marker-Based Kinship Matrix
- 3.4 Run EMMAX Association
- 3.5 Incorporating Covariates
- 3.6 Running EMMAX with dosages
- 4 Frequently asked Questions
- 4.1 Effect allele
- 4.2 Support for VCF format and Gene-level Burden Test
- 4.3 Encoding Case-control Phenotypes
- 4.4 IBS matrix or BN matrix?
- 4.5 NaN in the kinship file
- 4.6 Citing EMMAX
- 5 Acknowledgements
EMMAX is a statistical test for large scale human or model organism association mapping accounting for the sample structure. In addition to the computational efficiency obtained by EMMA algorithm, EMMAX takes advantage of the fact that each loci explains only a small fraction of complex traits, which allows us to avoid repetitive variance component estimation procedure, resulting in a significant amount of increase in computational time of association mapping using mixed model.
The latest release of EMMAX can be downloaded at EMMAX Download Page
The instruction is based on latest INTEL binary of EMMAX release. See http://genetics.cs.ucla.edu/emmax/ for the documentation of the original version of the binary
Preparing Input Genotype Files
Use PLINK software to transpose your genotype files (bed or ped format) to tped/tfam format by running % plink –bfile [bed_prefix] (or –file [ped_prefix]) –recode12 –output-missing-genotype 0 –transpose –out [tped_prefix]
Preparing Input Phenotype Files
Reformat the phenotype files in the same order of .tfam files. The phenotype file has three entries at each line, FAMID, INDID, and phenotype values. Missing phenotype values should be represented as “NA”. It is simpler to regress out the covariates when generating the phenotypes, but it is possible to simultaneously adjust for covariates.
Sample lines of phenotype files. (tab or space delimited)
859811 859811 0.609109817670387 862311 862311 -0.0735227335684144 864111 864111 -0.210247209814720 865211 865211 -0.154258680369780 875511 875511 0.239822160194388 880111 880111 0.287436401143001 880811 880811 NA 881511 881511 0.114872064616424 88211 88211 -0.0165529689285573
Creating Marker-Based Kinship Matrix
Create kinship matrix (IBS or BN, BN is preferred) using emmax-kin. Make sure that both .tped and .tfam file exist with the same prefix. The intel implementation of emmax-kin should be orders of magnitude faster than previous implementation
% emmax-kin-intel64 -v -s -d 10 [tped_prefix] (will generate [tped_prefix].aIBS.kinf)
BN (Balding-Nichols) matrix
% emmax-kin-intel64 -v -d 10 [tped_prefix] (will generate [tped_prefix].aBN.kinf)
Run EMMAX Association
Run EMMAX with the phenotype, tped/tfam files, and the kinship files as follows.
% emmax -v -d 10 -t [tped_prefix] -p [pheno_file] -k [kin_file] -o [out_prefix]
This will generate the following files:
- [out_prefix].reml : REML output with 6 lines, where each line represents
- Log-likelihood with variance component
- Log-likelihood without variance component
- \delta = \sigma_e^2 / \sigma_g^2 (Ratio between variance parameters)
- \sigma_g^2 (genetic variance parameter)
- sigma_e^2 (residual variance parameter)
- The pseudo-heritability estimates . (Explained variance by the kinship matrix)
- [out_prefix].ps : Each line consist of
- SNP ID
- Beta (1 is effect allele)
If one wants to adjust for covariates simultanenously, add -c [cov_file] options to the above run, with the covariate file similar to the phenotype files, but allowing multiple columns ( > 3 ). Note that the intercept has to be included, meaning that the third column is recommended to be 1 always, and the covariates needs to be included from the fourth column. The order of the individual IDs should conform to the .tfam files, similar to the phenotype files.
Sample lines of covariate files
100211 100211 1 2 100611 100611 1 2 100711 100711 1 3 100811 100811 1 4 101611 101611 1 2 101711 101711 1 2
Running EMMAX with dosages
If you add -Z option, it will accept .tped file format, where each individual is represented as one dosage value (ranging from 0 to 2), instead of two genotype columns, (which is one of the standard PLINK dosage format). You will be able to run EMMAX with this model. But when creating the kinship matrix, you will not be able to use dosage-based genotypes.
Frequently asked Questions
Q. Which allele is effect allele?
A. EMMAX simply follows the encoding scheme of .tped file in additive model. So whichever allele encoded as 2 in the .tped file, it will be the effect allele (usually the major allele)
Support for VCF format and Gene-level Burden Test
Q. Is there a version supporting VCF format and gene-level burden test?
A. Use EPACTS software pipeline for running EMMAX with VCF files, including the implementations of gene-level burden tests.
Encoding Case-control Phenotypes
Q. I would like to run EMMAX for case-control phenotypes. How can I encode the phenotypes?
A. If you encode case/control to 2/1, you will be able to run case-control analysis. Because EMMAX is based on linear mixed model rather than generalized mixed model, the effect size (beta) would not be meaningful, but the p-values should be reliable (unless case/control counts are highly imbalanced).
IBS matrix or BN matrix?
Q. Between IBS and BN matrix, which one is preferred?
A. We believe that BN matrix is more robust to construct the empirical kinship matrix. Also we recommend to use call rate 95% threshold and MAF threshold of 0.01 when preparing the data.
NaN in the kinship file
Q. I am observing a series of -nan in the kinship matrix. What is the problem?
A. Most likely, monomorphic SNPs would create such a problem. Typically, MAF threshold such as 1% is used.
Q. How can I cite EMMAX if I used it in my research?
A. Please see http://www.ncbi.nlm.nih.gov/pubmed/20208533 , or copy the line below.
Kang HM, Sul JH, Service SK, Zaitlen NA, Kong SY, Freimer NB, Sabatti C, Eskin E. (2010) Variance component model to account for sample structure in genome-wide association studies. Nat. Genet. 42:348-54
This research was supported by National Science Foundation grants 0513612, 0731455 and 0729049, and National Institutes of Health (NIH) grants 1K25HL080079 and U01-DA024417. N.A.Z. is supported by the Microsoft Research Fellowship. H.M.K. is supported by the Samsung Scholarship, National Human Genome Research Institute grant HG00521401, National Institute for Mental Health grant NH084698 and GlaxoSmithKline. C.S. is partially supported by NIH grants GM053275-14, HL087679-01, P30 1MH083268, 5PL1NS062410-03, 5UL1DE019580-03 and 5RL1MH083268-03. N.B.F. and S.K.S. are supported by NIH grants HL087679-03, 5PL1NS062410-03, 5UL1DE019580-03 and 5RL1MH083268-03. This research was supported in part by the University of California, Los Angeles subcontract of contract N01-ES-45530 from the National Toxicology Program and National Institute of Environmental Health Sciences to Perlegen Sciences.
- This page was last edited on 2 February 2017, at 09:58.
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