Hi!
when i'm trying to compile this lite example
on my linux machine I'll get errors and i don't know why..
#include <stdio.h>
#include <math.h> /* needed by sqrt() */
int main()
{
printf("%f", sqrt(10.0));
return (0);
}
this is the error:
/tmp/cc33hNVHK.o: In function... (1 Reply)
I was writing a simple program in linux, which includes sqrt function of c.
I included the math.h. But when I use gcc to compile it, it gave an error message:
/home/murat/tmp/ccOv9upo.o(.text+0x4b): In function `main':
: undefined reference to `sqrt'
collect2: ld returned 1 exit status
I... (2 Replies)
HI,
I have a file which i catenate and using the fields in the file, I would like to get sqrt of it. I tried to man the function but it normally would need an echo as well as bc.
What I am intending to find out is catenate a file where let say
cat a.txt| awk ' {
t= h*($3+$2);
t=... (7 Replies)
I have looked for hours for an answer, so I have decided to request your guidance.
I want to substract the first number (series of digits) contained in a string. This string is the output of another command. The substring (number) can be located at any position inside the string.
I want to... (4 Replies)
Hi there!
I'm trying to validate a simple 6 digits number with reg expr. I ONLY want 6 digits so when i type 7 digits the script should no validate the number.
I've write this code:
#!/usr/bin/perl
while(<STDIN>){
if($_=~/\d{6}/){
print "Bingo!\n";
... (2 Replies)
This so basic that it should work.... Any ideas would be appreciared. Using a number directly in the sqrt allows it to compile.
primrose > cat a.c
#include <stdio.h>
#include <math.h>
int main(void)
{
double abcd=9;
printf("%f\n",sqrt(abcd));
}
primrose > gcc a.c
Undefined first... (2 Replies)
Hi,
i have a the following script:
#!/bin/bash
a=3
b=9
let "c= b*a"
let "d=sqrt $c "
echo $d
But when i execute the code, it gives me the an error saying:
line 5: let: d=sqrt 27 : syntax error in expression (error token is "27 ")
Can any body tell me what I'm doing wrong? (5 Replies)
Hi, I would like to use find command to find file with a predefined extension
for example find . modules/*.ksh *.lib
I thought it's possible to use something like :
find . modules/*. but it does not work. is there any other way?
Thanks you (2 Replies)
Hi
I want to use awk to match where field 3 contains a number within string - then print the line and just the number as a new field.
The source file is pipe delimited and looks something like
1|net|ABC Letr1|1530|||
1|net|EXP_1040 ABC|1121|||
1|net|EXP_TG1224|1122|||
1|net|R_North|1123|||... (5 Replies)
Hi all...
This is just a fun project to see if it is possible to get a square root of a positive integer from 1 to 9200000 to 6 decimal places on a 64 bit architecture machine.
It is coded around dash and the results show the values from 0 to 10000.
Complex numbers can easily be catered for by... (3 Replies)
Discussion started by: wisecracker
3 Replies
LEARN ABOUT BSD
expr
EXPR(1) General Commands Manual EXPR(1)NAME
expr - evaluate arguments as an expression
SYNOPSIS
expr arg ...
DESCRIPTION
The arguments are taken as an expression. After evaluation, the result is written on the standard output. Each token of the expression is
a separate argument.
The operators and keywords are listed below. The list is in order of increasing precedence, with equal precedence operators grouped.
expr | expr
yields the first expr if it is neither null nor `0', otherwise yields the second expr.
expr & expr
yields the first expr if neither expr is null or `0', otherwise yields `0'.
expr relop expr
where relop is one of < <= = != >= >, yields `1' if the indicated comparison is true, `0' if false. The comparison is numeric if
both expr are integers, otherwise lexicographic.
expr + expr
expr - expr
addition or subtraction of the arguments.
expr * expr
expr / expr
expr % expr
multiplication, division, or remainder of the arguments.
expr : expr
The matching operator compares the string first argument with the regular expression second argument; regular expression syntax is
the same as that of ed(1). The (...) pattern symbols can be used to select a portion of the first argument. Otherwise, the
matching operator yields the number of characters matched (`0' on failure).
( expr )
parentheses for grouping.
Examples:
To add 1 to the Shell variable a:
a=`expr $a + 1`
To find the filename part (least significant part) of the pathname stored in variable a, which may or may not contain `/':
expr $a : '.*/(.*)' '|' $a
Note the quoted Shell metacharacters.
SEE ALSO sh(1), test(1)DIAGNOSTICS
Expr returns the following exit codes:
0 if the expression is neither null nor `0',
1 if the expression is null or `0',
2 for invalid expressions.
7th Edition April 29, 1985 EXPR(1)