    const std = @import("../../std.zig");
    const testing = std.testing;
    const math = std.math;
    const cmath = math.complex;
    const Complex = cmath.Complex;

    /// Returns the absolute value (modulus) of z.
    pub fn abs(z: anytype) @TypeOf(z.re) {
        const T = @TypeOf(z.re);
        return math.hypot(T, z.re, z.im);
    }

    const epsilon = 0.0001;

    test "complex.cabs" {
        const a = Complex(f32).init(5, 3);
        const c = abs(a);
        try testing.expect(math.approxEqAbs(f32, c, 5.83095, epsilon));
    }