| 1 | const std = @import("../../std.zig"); |
| 2 | const testing = std.testing; |
| 3 | const math = std.math; |
| 4 | const cmath = math.complex; |
| 5 | const Complex = cmath.Complex; |
| 6 | |
| 7 | /// Returns the hyperbolic arc-tangent of z. |
| 8 | pub fn atanh(z: anytype) Complex(@TypeOf(z.re, z.im)) { |
| 9 | const T = @TypeOf(z.re, z.im); |
| 10 | const q = Complex(T).init(-z.im, z.re); |
| 11 | const r = cmath.atan(q); |
| 12 | return Complex(T).init(r.im, -r.re); |
| 13 | } |
| 14 | |
| 15 | test atanh { |
| 16 | const epsilon = math.floatEps(f32); |
| 17 | const a = Complex(f32).init(5, 3); |
| 18 | const c = atanh(a); |
| 19 | |
| 20 | try testing.expectApproxEqAbs(0.14694665, c.re, epsilon); |
| 21 | try testing.expectApproxEqAbs(1.4808695, c.im, epsilon); |
| 22 | } |