const std = @import("../../std.zig"); const testing = std.testing; const math = std.math; const cmath = math.complex; const Complex = cmath.Complex; /// Returns the cosine of z. pub fn cos(z: var) Complex(@typeOf(z.re)) { const T = @typeOf(z.re); const p = Complex(T).new(-z.im, z.re); return cmath.cosh(p); } const epsilon = 0.0001; test "complex.ccos" { const a = Complex(f32).new(5, 3); const c = cos(a); testing.expect(math.approxEq(f32, c.re, 2.855815, epsilon)); testing.expect(math.approxEq(f32, c.im, 9.606383, epsilon)); }