zig/lib/std/math/complex/asin.zig
Robin Voetter 4b4fbe3887
Replace @typeOf with @TypeOf in all zig source
This change was mostly made with `zig fmt` and this also modified some whitespace. Note that in some files, `zig fmt` produced incorrect code, so the change was made manually.
2019-12-10 11:09:41 -05:00

29 lines
734 B
Zig

const std = @import("../../std.zig");
const testing = std.testing;
const math = std.math;
const cmath = math.complex;
const Complex = cmath.Complex;
// Returns the arc-sine of z.
pub fn asin(z: var) Complex(@TypeOf(z.re)) {
const T = @TypeOf(z.re);
const x = z.re;
const y = z.im;
const p = Complex(T).new(1.0 - (x - y) * (x + y), -2.0 * x * y);
const q = Complex(T).new(-y, x);
const r = cmath.log(q.add(cmath.sqrt(p)));
return Complex(T).new(r.im, -r.re);
}
const epsilon = 0.0001;
test "complex.casin" {
const a = Complex(f32).new(5, 3);
const c = asin(a);
testing.expect(math.approxEq(f32, c.re, 1.023822, epsilon));
testing.expect(math.approxEq(f32, c.im, 2.452914, epsilon));
}