asin, asinl

Remonter à Math.h - Index

Header File

math.h

Category

Math Routines

Prototype

double asin(double x);

long double asinl(long double x);

Description

Calculates the arc sine.

asin of a real argument returns the arc sine of the input value.

asinl is the long double version; it takes a long double argument and returns a long double result.

Real arguments to asin and asinl must be in the range -1 to 1, or else asin and asinl return NAN and set the global variable errno to

EDOM Domain error

Return Value

asin and asinl of a real argument return a value in the range -pi/2 to pi/2. Error handling for these functions may be modified through the functions _matherr and _matherrl.

Example

 #include <stdio.h>
 #include <math.h>
 int main(void)
 {
    double result;
    double x = 0.5;
    result = asin(x);
    printf("The arc sin of %lf is %lf\n", x, result);
   return(0);
 }

Portability

	POSIX	Win32	ANSI C	ANSI C++
asin	+	+	+	+
asinl		+	+	+