• greatsam4sure (6/6) Aug 06 2017 import std.math;
• sarn (10/16) Aug 06 2017 That's just floating point maths for you. You're not putting
• Nicholas Wilson (3/9) Aug 06 2017 in addition to what sarn said, tan(3pi/4) is a pole, not
• greatsam4sure (3/14) Aug 07 2017 Thanks for the help. I will appreciate any resources for further

greatsam4sure <greatsam4sure gmail.com> writes:

import std.math;
import std.stdio;

cos(90*PI/180) = -2.7e-20 instead of zero. I will appreciate any 
help. thanks in advance.

tan(90*PI/180) = -3.689e+19 instead of infinity. What is the best 
way to use this module

sarn <sarn theartofmachinery.com> writes:

On Sunday, 6 August 2017 at 23:33:26 UTC, greatsam4sure wrote:
 import std.math;
 import std.stdio;

 cos(90*PI/180) = -2.7e-20 instead of zero. I will appreciate 
 any help. thanks in advance.

 tan(90*PI/180) = -3.689e+19 instead of infinity. What is the 
 best way to use this module

That's just floating point maths for you.  You're not putting 
exactly pi/2 into cos, just a good floating point approximation.  
What you're getting out isn't exactly 0, either, just a good 
floating point approximation.  (-2.7e-20 is really, really small.)

Here's a good talk from DConf 2016: 
https://www.youtube.com/watch?v=97bxjeP3LzY

If you need exact maths, you'll need a symbolic manipulation 
library (never used one in D, but there was a discussion recently 
https://forum.dlang.org/thread/ghihookwgzxculshibyc forum.dlang.org).  You
don't need this for most practical applications, though.

Nicholas Wilson <iamthewilsonator hotmail.com> writes:

On Sunday, 6 August 2017 at 23:33:26 UTC, greatsam4sure wrote:
 import std.math;
 import std.stdio;

 cos(90*PI/180) = -2.7e-20 instead of zero. I will appreciate 
 any help. thanks in advance.

 tan(90*PI/180) = -3.689e+19 instead of infinity. What is the 
 best way to use this module

in addition to what sarn said, tan(3pi/4) is a pole, not 
infinity. the mean of the left and right hand limits is 0

greatsam4sure <greatsam4sure gmail.com> writes:

On Monday, 7 August 2017 at 04:47:56 UTC, Nicholas Wilson wrote:
 On Sunday, 6 August 2017 at 23:33:26 UTC, greatsam4sure wrote:
 import std.math;
 import std.stdio;

 cos(90*PI/180) = -2.7e-20 instead of zero. I will appreciate 
 any help. thanks in advance.

 tan(90*PI/180) = -3.689e+19 instead of infinity. What is the 
 best way to use this module

 in addition to what sarn said, tan(3pi/4) is a pole, not 
 infinity. the mean of the left and right hand limits is 0

Thanks for the help. I will appreciate any resources for further 
reading