Upgrade to PRO for Only $50/Year—Limited-Time Offer! 🔥
Speaker Deck
Features
Speaker Deck
PRO
Sign in
Sign up for free
Search
Search
小数の丸め誤差の話
Search
circled9
July 26, 2024
Programming
0
150
小数の丸め誤差の話
Niigata5分Tech #10の発表資料です。
https://niigata-5min-tech.connpass.com/event/324842/
circled9
July 26, 2024
Tweet
Share
More Decks by circled9
See All by circled9
キースイッチ入門
circled9
0
88
CloudflareのAI関連の機能さわってみた
circled9
0
750
0.0.0.0 day
circled9
0
110
数値の文字列をパースしよう
circled9
0
240
🔥 Hono v4 やってみた
circled9
1
210
JetBrains AI Assistant を試してみた
circled9
1
550
Fresh
circled9
0
260
React Hooks 勉強会 vol.3
circled9
2
450
JSON.stringify()
circled9
2
500
Other Decks in Programming
See All in Programming
Building AI Agents with TypeScript #TSKaigiHokuriku
izumin5210
6
1.2k
TUIライブラリつくってみた / i-just-make-TUI-library
kazto
1
360
関数実行の裏側では何が起きているのか?
minop1205
1
680
ID管理機能開発の裏側 高速にSaaS連携を実現したチームのAI活用編
atzzcokek
0
210
Why Kotlin? 電子カルテを Kotlin で開発する理由 / Why Kotlin? at Henry
agatan
2
6.9k
モデル駆動設計をやってみようワークショップ開催報告(Modeling Forum2025) / model driven design workshop report
haru860
0
260
SwiftUIで本格音ゲー実装してみた
hypebeans
0
110
複数人でのCLI/Infrastructure as Codeの暮らしを良くする
shmokmt
5
2.2k
DSPy Meetup Tokyo #1 - はじめてのDSPy
masahiro_nishimi
1
160
20 years of Symfony, what's next?
fabpot
2
350
Navigation 3: 적응형 UI를 위한 앱 탐색
fornewid
1
220
配送計画の均等化機能を提供する取り組みについて(⽩⾦鉱業 Meetup Vol.21@六本⽊(数理最適化編))
izu_nori
0
140
Featured
See All Featured
Six Lessons from altMBA
skipperchong
29
4.1k
Optimizing for Happiness
mojombo
379
70k
Navigating Team Friction
lara
191
16k
Writing Fast Ruby
sferik
630
62k
Save Time (by Creating Custom Rails Generators)
garrettdimon
PRO
32
1.8k
Helping Users Find Their Own Way: Creating Modern Search Experiences
danielanewman
31
3k
CSS Pre-Processors: Stylus, Less & Sass
bermonpainter
359
30k
GraphQLの誤解/rethinking-graphql
sonatard
73
11k
RailsConf & Balkan Ruby 2019: The Past, Present, and Future of Rails at GitHub
eileencodes
141
34k
VelocityConf: Rendering Performance Case Studies
addyosmani
333
24k
For a Future-Friendly Web
brad_frost
180
10k
The MySQL Ecosystem @ GitHub 2015
samlambert
251
13k
Transcript
খͷؙΊޡࠩͷ Niigata 5min Tech #10 @circled9 1
ࣗݾհ @circled9 দҪɹਖ਼ࢤ / Matsui Masashi גࣜձࣾϞχΫϧ جຊใٕज़ऀͷࢿ֨͋Γ·͕͢ هԱ͋Γ·ͤΜ 2
ࠓখͷؙΊޡࠩͷΛ͠·͢ 3
Node.js 4
Ͳ͏ͯ͠ʁ • ଟ͘ͷϓϩάϥϛϯάݴޠɺ෦తʹΛೋਐͰѻ͍ͬͯΔ • ेਐͷখΛೋਐʹม͢Δͱޡ͕ࠩੜ͡Δ߹͕͋Δ • Ή͠Ζޡ͕ࠩग़ͳ͍ํ͕গͳ͍ͷͰ...? 5
ेਐͷখΛೋਐͰද͢ͷ͍͠ • ೋਐͷͷNܻ2ͷN-1ͷ 1 1 1 1 = 15 8
4 2 1 • ҰํɺೋਐͷখͷNܻ2ͷϚΠφεN-1ͷ 0. 1 1 1 = 0.5 + 0.25 + 0.125 = 0.875 1 1/2 1/4 1/8 • 2ͷϚΠφεNͷΈ߹ΘͤͰਖ਼֬ʹදݱͰ͖Δʹݶք͕͋Δ 6
Node.js 7
Ͳ͏͢ΕޡࠩΛ͛Δ͔ • খͷܭࢉΛͯ͠େৎͳܕͳͲΛ͏ • খͰͳ͘ͷܭࢉʹ͢Δ 8
খͷܭࢉΛͯ͠େৎͳܕͳͲΛ͏ • C#ͷ߹decimalܕ͕͋Δ • Pythonͷ߹decimalϞδϡʔϧ͕͋Δ • JavaScriptͷ߹big.jsͳͲͷϥΠϒϥϦ͕͋Δ 9
Python 10
খͰͳ͘ͷܭࢉʹ͢Δ • ܭࢉ͢Δલʹʹͯ͠ɺܭࢉޙʹখʹ͢ • ྫ͑100Λ͔͚ͯɺ࠷ޙʹ100ͰׂΔ • ((0.1 * 100) +
(0.2 * 100)) / 100 • ͜ͷ߹ɺܭࢉରͷͷܻΛؾʹ͢Δඞཁ͕͋Δ 11
Node.js 12
·ͱΊ • ଟ͘ͷϓϩάϥϛϯάݴޠͰɺখͷܭࢉͰޡ͕ࠩൃੜ͢Δ • ޡࠩΛग़͞ͳ͍Α͏ʹ͢ΔʹదͳରԠΛ͢Δඞཁ͕͋Δ 13
ଟ͘ͷϓϩάϥϛϯάݴޠʁ 14
খͷܭࢉͰޡࠩͷग़ͳ͍ϓϩάϥϛϯάݴޠ • COBOL • Ada • MSX-BASIC • etc... දݱʹBCDΛ͏ͷ͕ϙΠϯτͬΆ͍
15
BCD • Binary-Coded DecimalɺೋਐԽेਐ • ೋਐ4ܻ͋Ε0͔Β15·ͰͷΛදͤΔͷͰɺ0͔Β9Λͬ ͯेਐͷҰܻΛදݱ͢Δ • ྫ͑ेਐͷ26ɺBCDͰ 0010
0110 ʹͳΔ • BCDجຊใٕज़ऀࢼݧͷࢼݧൣғʹؚ·Ε͍ͯΔ 16
BCDجຊใٕज़ऀࢼݧͷ ࢼݧൣғʹؚ·Ε͍ͯΔ 17
શʹΕͯͨͱ͍͏͔ ֮͑ͨهԱ͢Βͳ͍😇 18
Goݴޠ 19
20
https://go.dev/ref/spec#Constant_expressions υΩϡϝϯτᐌ͘ ఆࣜৗʹਖ਼֬ʹධՁ͞Ε·͢ Constant expressions are always evaluated exactly; 21
22
͓͠·͍ 23
ࢀߟࢿྉ • খΛѻ͏ͳΒBCDΛ࠾༻͍ͯ͠Δݴޠ͕ѹత • https://qiita.com/ma2shita/items/d8aeec9e2921dc3536f4 24