From:	"George Kinney" <goober AT mail DOT net>
Subject:	Re: Why doesn't this work (correct, running code)
Newsgroups:	comp.os.msdos.djgpp
References:	<5qf224$6m0$1 AT missing DOT link DOT ca>
Organization:	The Unknown Programmers
Message-ID:	<01bc91cf$959d40e0$e68033cf@pentium>
NNTP-Posting-Host:	207.51.128.230
Date:	16 Jul 97 09:55:05 GMT
Lines:	53
To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp

James Edwin Cooper <ab837 AT sfn DOT saskatoon DOT sk DOT ca> wrote in article
<5qf224$6m0$1 AT missing DOT link DOT ca>...
> Sorry, me again! Anyway, I just made this program, changed it until there

> weren't any DAMN errors, and now it doesn't work! It is a SUPER fast SIN 
> calculator (integer values only). The problem is, no matter WHAT number 
> you type in, it always pumps out 0.000000. Any reason?
> 
> *** WARNING: DJGPP V1 CODE START ***

Get DJGPP v2+ ! It'll save you many headaches. (As well as being supported)

[CLIP]
>  float answer,sintable[360];
[CLIP]
>  for(i=0;i<360;i++)
>  {
>   sintable[i]=sin(i);
>   printf(".");
>  }

sin takes radians,  not degrees.  The values stored in sintable are most
certainly not what you seem to think they are.

[SNIP]
>  printf("\nThe answer is %f.\n\n");

I hope this is a typo.  It should read:
printf( "\nThe answer is %f.\n\n", answer );

It would certainly be beneficial to you to get a good book on the C
language,
or at least check the standard librarys reference when calling a function
so
that you can make sure you are actually using it properly,  and that it
will
do what you expect. (if used properly that is)

[CLIP]

> Sorry if this doesn't look perfect or run fast, it was a 15 minute hack 
> by a newbie. Anyway, If this should work, then can you give me hints? 
> Otherwise, a simple fix would be nice! Thanks in advance :)

Also,  print out the contents of sintable after your calculations,
you'll notice that it is a string of numbers that are actually the 
sin values taken every ~60 degrees or so.  

If you don't know what a radian is,  get a math book to go along with 
the C book. (HINT: there are 2PI radians in a circle)

And above all,  read the info files on the library functions you intend to
use,  it will save you from many errors like these.

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