Bioequivalence and Bioavailability Forum • Spreadsheet failures, any recent examples?

Spreadsheet failures, any recent examples? [Software]

posted by Ohlbe – France, 2020-12-10 19:43 (1621 d 02:30 ago) – Posting: # 22125
Views: 19,030

Dear ElMaestro,

❝ does anyone have recent examples of spreadsheet functions truly misbehaving with real-life realistic data?

A colleague recently pointed to a strange behaviour in Excel (I have 2013, he has 2016, both give the same result here.

Type =0.5-0.4-0.1: you'll get the expected result, 0.

Now type =(0.5-0.4-0.1): you'll get -2,77556E-17. What ? Ain't that supposed to be the same calculation?

Trying =0=0.5-0.4-0.1: the answer I got was FALSE. WTF, if the answer you get is 0? It's not a matter of number of decimals displayed: I tried to add more to the first result, or to switch to scientific notation, but still got 0.

—
Regards
Ohlbe

Complete thread:

Spreadsheet failures, any recent examples? ElMaestro 2019-07-18 13:43 [Software]
- Spreadsheet failures, any recent examples? Ohlbe 2019-07-18 14:32
  - Spreadsheet addiction Helmut 2019-07-18 16:12
    - Nasty beast Ohlbe 2019-07-18 17:30
      - Nasty beast Helmut 2019-07-18 20:26
        
        Nasty beast Ohlbe 2019-07-19 11:32
        
        Nasty beast ElMaestro 2019-07-19 12:32
        
        Decidedly off topic Ohlbe 2019-07-19 13:38
        
        OT: R limbo 101 Helmut 2019-07-19 13:00
    - Spreadsheet addiction Shuanghe 2019-07-18 18:59
      - Spreadsheet addiction Helmut 2019-07-18 20:04
        
        OT: Spreadsheet addiction Shuanghe 2019-07-19 12:41
        
        OT: Spreadsheet addiction Helmut 2019-07-19 14:29
        
        OT: Spreadsheet addiction nobody 2019-07-19 15:53
        
        OT: Spreadsheet addiction Helmut 2019-07-19 19:32
  - Spreadsheet etc. failures zizou 2019-07-20 00:18
    - As designed ☺ Helmut 2019-07-20 02:12
      - As designed ☺ ElMaestro 2019-07-20 09:08
        
        To round or not to round… Helmut 2019-07-20 12:53
        
        To round or not to round… ElMaestro 2019-07-20 19:59
        
        floating-point math is always more complex than you think it is mittyri 2019-07-20 22:43
- Spreadsheet failures, any recent examples?Ohlbe 2020-12-10 18:43
  - Floating point arithmetic, again Helmut 2020-12-10 19:12
    - Floating point arithmetic, again ElMaestro 2020-12-10 19:40
      - Floating point arithmetic, again Ohlbe 2020-12-10 20:18
        
        Floating point arithmetic, again ElMaestro 2020-12-10 21:38
        
        Floating point arithmetic, again Ohlbe 2020-12-10 21:46
        
        Floating point arithmetic, again ElMaestro 2020-12-10 22:05
        
        Depressed Ohlbe 2020-12-10 23:35
        
        Depressed ElMaestro 2020-12-11 07:59
    - Floating point arithmetic, again Ohlbe 2020-12-10 20:13
  - From bad to worse Ohlbe 2020-12-10 22:11
    - From bad to worse mittyri 2020-12-11 00:22
    - All is good Helmut 2020-12-11 00:36
      - Float is float PharmCat 2020-12-18 20:53
        
        Float is float! Helmut 2020-12-20 23:27
        
        rational solution in R mittyri 2020-12-21 13:49
        
        related stuff Helmut 2021-01-14 12:53
        
        related stuff SDavis 2021-02-09 12:02
        
        related stuff ElMaestro 2021-02-09 19:55