Article View: comp.unix.shell
Article #993Math routines (was bourne shell query)
From: Jeffrey Gleixner
Date: Sun, 02 Sep 1990 14:16
Date: Sun, 02 Sep 1990 14:16
38 lines
1754 bytes
1754 bytes
In article <75@iconsys>, mday@iconsys (Matt Day) writes:
> In article <SCOTT.90Aug30124930@tab00.larc.nasa.gov>
scott@tab00.larc.nasa.gov (Scott Yelich) writes:
> >As a side question, does ANYONE have any bourne shell routines which do
> >math... reasonably effeciently? (For numbers > 1000?)
>
> For the Bourne shell, the most efficient way to do math is to use the "expr"
> ... If you have a shell script that needs to do
> a lot of math, I suggest you use the C shell built in math operators; it's
If you're going to do a lot of math write a {your favorite language besides
*sh here} program to do the math for you. Even if you're doing a small
amount of math it will really speed it up.
i.e.
#!/bin/sh
count 1 6 | while read value ; do
some commands...
done
=========
/*
* Count.c
*
* print succesive numbers from start to end.
* Used in scripts instead of `expr $i +1`
*/
#include <stdio.h>
main(argc,argv)
int argc; char *argv[];
{
register int i,j;
i=atoi(argv[1]);
j=atoi(argv[2]);
while (i <= j)
printf(" %d",i++);
}
--
glex@msc.umn.edu === " I don't go out with girls that say bitch'n " ===
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Path: arc1-ca.pugleaf.net!utzoo!utgpu!watserv1!watmath!att!rutgers!ub.d.umn.edu!cs.umn.edu!uc!uh.msc.umn.edu!glex From: glex@uh.msc.umn.edu (Jeffrey Gleixner) Newsgroups: comp.unix.shell Subject: Math routines (was bourne shell query) Keywords: Use C Message-ID: <2494@uc.msc.umn.edu> Date: 2 Sep 90 14:16:01 GMT References: <26DC6447.15922@maccs.dcss.mcmaster.ca> <8446@orca.wv.tek.com> <SCOTT.90Aug30124930@tab00.larc.nasa.gov> <75@iconsys> Sender: news@uc.msc.umn.edu Reply-To: glex@uh.msc.umn.edu (Jeffrey Gleixner) Organization: Minnesota Supercomputer Center Lines: 38