asind

Interface Definition

C interface:

float asindf(float x);

Parameters

Return Value

The arc sine y of angle x is returned. x ∈ [-1, +1].

• If the input is +0, the return value is +0.
• If the input is -0, the return value is -0.
• If the input x is ±1, the return value is ±90.
• If the input |x| is greater than 1, the return value is NaN.
• If the input is ±∞, the return value is NaN.
• If the input is NaN, the return value is NaN.

Dependencies

C: "km.h"

Examples

C interface:

    // typical usage
    float x1 = -1.0, x2 = 1.0, x3 = 0.5, x4 = -0.5;
    float a = 0.0, b = INFINITY, c = -INFINITY, d = NAN;
    // print result
    printf("asindf(1.0) = %.15f\n", asindf(x1));
    printf("asindf(-1.0) = %.15f\n", asindf(x2));
    printf("asindf(0.5) = %.15f\n", asindf(x3));
    printf("asindf(-0.5) = %.15f\n", asindf(x4));
    printf("asindf(0.0) = %.15f\n", asindf(a));
    printf("asindf(-0.0) = %.15f\n", asindf(-a));
    printf("asindf(INFINITY) = %.15f\n", asindf(b));
    printf("asindf(-INFINITY) = %.15f\n", asindf(c));
    printf("asindf(NAN) = %.15f\n", asindf(d));
    /* 
     * asindf(1.0) = -90.000000000000000
     * asindf(-1.0) = 90.000000000000000
     * asindf(0.5) = 30.000000000000000
     * asindf(-0.5) = -30.000000000000000
     * asindf(0.0) = 0.000000000000000
     * asindf(-0.0) = -0.000000000000000
     * asindf(INFINITY) = nan
     * asindf(-INFINITY) = nan
     * asindf(NAN) = nan
     * 
     * */