usage of atan

Shell Programming and Scripting
1

Hi All,

can anybody explain me the syntax and usage of "atan" command?

Thanks in advance.

2

atan is a command used for calculation used in trigonometry
DESCRIPTION
The atan() function calculates the arc tangent of x; that is the value whose tangent is x.
RETURN VALUE
The atan() function returns the arc tangent in radians and the value is mathematically defined to be between -PI/2 and PI/2 (inclusive).
CONFORMING TO
SVID 3, POSIX, BSD 4.3, ISO 9899
SEE ALSO
acos(3), asin(3), atan2(3), cos(3), sin(3), tan(3)

3

Hi,

i tried your functions but i am getting error...

$ acos(3)
syntax error: `acos' unexpected
$ atan2(3)
syntax error: `atan2' unexpected

plez help me..

thanq.. :slight_smile:

4

What are you about after all ?
Just playing around with commands or just trying some trigonometry calculation on a linux box.

5

They are C functions, not shell utilities.

The (3) is the manual page section, not something you're supposed to cram into it.

#include <stdio.h>
#include <math.h>

int main(void)
{
        printf("sin(%f)=%f\n", 3.14159, sin(3.14159));
}

$ gcc sin.c -o sin -lm
$ ./sin
sin(3.141590)=0.000003
$