Re: Incorrect expression calculation between programming languages

[Domingo Alvarez Duarte <mingodad@...>]

Hello Oliver !

Thanks for reply !

One of my objectives is to make awareness of this possible problems 
between different programming languages and provide test cases to help 
identify the problems and hopefully have a consensus between then to 
allow code reuse with fewer/no traps.

Cheers !

On 6/8/21 15:49, Oliver Kroth wrote:
> removing brackets around constants and bracketed terms leaves this 
> expression:
> (( (   788 * 8.46   )+8342*1.803-1 )*4186.4* 15 )*( (22 % 284/( 7530/( 
> 2 *(    25  -421  )) )*597 % 2663)+7283.8-9.60+167.8644 % 3   )+ 8871
>
> And that reveals that some of the modulo operations are NOT guarded by 
> brackets; i.e. the language's operator preference decides in which 
> order the operands are computed.
>
> E.g. 1 / 2 % 3 may be (1/2) % 3 or 1 / (2%3)
> similar multiplication:
> 1 * 2 % 3 can be (1*2) % 3 or 1 * (2%3)
>
> That could explain some of the differences.
>
> Oliver
>
>
> Am 06.08.21 um 14:31 schrieb Domingo Alvarez Duarte:
> > This expression shows that we have several disagreements between 
> > programming languages about what is the end result:
> > =====
> >
> > EXPR = 
> > (((((((788)*(8.46))))+8342*1.803-1))*4186.4*(15))*(((22%284/((7530/((2)*(((((25))-421))))))*597%2663)+7283.8-9.60+167.8644%((3))))+(8871)
> >
> > POSTGRESQL = 8291561284461.33301440
> >
> > SQUILU = 8291561284461.3
> >
> > JAVA = 8.291561284461331E12
> >
> > D = 8.29156e+12
> >
> > SQLITE = 8290383058308.3
> >
> > PHP = 8035491468054
> >
> > JAVSCRIPT = 8036090802426.098
> >
> > MYSQL = 8036090802312.071
> >
> > PYTHON = 1.1107636287e+13
> >
> > RUBY = 11107636286950.146
> >
> > LUA = 11665910614443
> >
> > =====
> >
> > And making all operands to modulo operator "%" integer:
> > =====
> >
> > EXPR = 
> > (((((((788)*(8.46))))+8342*1.803-1))*4186.4*(15))*(((22%284/((7530/((2)*(((((25))-421))))))*597%2663)+7283.8-9.60+167%((3))))+(8871)
> >
> > D = 8.29038e+12
> >
> > JAVA = 8.290383058308305E12
> >
> > MYSQL = 8034912576159.046
> >
> > POSTGRESQL = 8290383058308.307200
> >
> > SQLITE = 8290383058308.3
> >
> > SQUILU = 8291561284461.3
> >
> > JAVASCRIPT = 8034912576273.071
> >
> > PHP = 8035491468054
> >
> > AMPL = 8.03491e+12
> >
> > GAMS = 8.03491E+12
> >
> > PYTHON = 1.11064580608e+13
> >
> > RUBY = 11106458060797.121
> >
> > LUA = 11664732388290
> >
> > ====
> >
> >
> > See also posted here https://news.ycombinator.com/item?id=28085642 
> > and https://sqlite.org/forum/forumpost/6885cf9e21