Merge pull request #20878 from tiehuis/std-math-complex-fixes

std.math.complex fixes
ziglang · Aug 1, 2024 · 059856a · 059856a
2 parents 7c5ee3e + 8438855
commit 059856a
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Showing 19 changed files with 102 additions and 120 deletions.
diff --git a/lib/std/math/complex/abs.zig b/lib/std/math/complex/abs.zig
@@ -9,10 +9,9 @@ pub fn abs(z: anytype) @TypeOf(z.re, z.im) {
     return math.hypot(z.re, z.im);
 }
 
-const epsilon = 0.0001;
-
 test abs {
+    const epsilon = math.floatEps(f32);
     const a = Complex(f32).init(5, 3);
     const c = abs(a);
-    try testing.expect(math.approxEqAbs(f32, c, 5.83095, epsilon));
+    try testing.expectApproxEqAbs(5.8309517, c, epsilon);
 }
diff --git a/lib/std/math/complex/acos.zig b/lib/std/math/complex/acos.zig
@@ -11,12 +11,11 @@ pub fn acos(z: anytype) Complex(@TypeOf(z.re, z.im)) {
     return Complex(T).init(@as(T, math.pi) / 2 - q.re, -q.im);
 }
 
-const epsilon = 0.0001;
-
 test acos {
+    const epsilon = math.floatEps(f32);
     const a = Complex(f32).init(5, 3);
     const c = acos(a);
 
-    try testing.expect(math.approxEqAbs(f32, c.re, 0.546975, epsilon));
-    try testing.expect(math.approxEqAbs(f32, c.im, -2.452914, epsilon));
+    try testing.expectApproxEqAbs(0.5469737, c.re, epsilon);
+    try testing.expectApproxEqAbs(-2.4529128, c.im, epsilon);
 }
diff --git a/lib/std/math/complex/acosh.zig b/lib/std/math/complex/acosh.zig
@@ -8,15 +8,18 @@ const Complex = cmath.Complex;
 pub fn acosh(z: anytype) Complex(@TypeOf(z.re, z.im)) {
     const T = @TypeOf(z.re, z.im);
     const q = cmath.acos(z);
-    return Complex(T).init(-q.im, q.re);
-}
 
-const epsilon = 0.0001;
+    return if (math.signbit(z.im))
+        Complex(T).init(q.im, -q.re)
+    else
+        Complex(T).init(-q.im, q.re);
+}
 
 test acosh {
+    const epsilon = math.floatEps(f32);
     const a = Complex(f32).init(5, 3);
     const c = acosh(a);
 
-    try testing.expect(math.approxEqAbs(f32, c.re, 2.452914, epsilon));
-    try testing.expect(math.approxEqAbs(f32, c.im, 0.546975, epsilon));
+    try testing.expectApproxEqAbs(2.4529128, c.re, epsilon);
+    try testing.expectApproxEqAbs(0.5469737, c.im, epsilon);
 }
diff --git a/lib/std/math/complex/arg.zig b/lib/std/math/complex/arg.zig
@@ -9,10 +9,9 @@ pub fn arg(z: anytype) @TypeOf(z.re, z.im) {
     return math.atan2(z.im, z.re);
 }
 
-const epsilon = 0.0001;
-
 test arg {
+    const epsilon = math.floatEps(f32);
     const a = Complex(f32).init(5, 3);
     const c = arg(a);
-    try testing.expect(math.approxEqAbs(f32, c, 0.540420, epsilon));
+    try testing.expectApproxEqAbs(0.5404195, c, epsilon);
 }
diff --git a/lib/std/math/complex/asin.zig b/lib/std/math/complex/asin.zig
@@ -17,12 +17,11 @@ pub fn asin(z: anytype) Complex(@TypeOf(z.re, z.im)) {
     return Complex(T).init(r.im, -r.re);
 }
 
-const epsilon = 0.0001;
-
 test asin {
+    const epsilon = math.floatEps(f32);
     const a = Complex(f32).init(5, 3);
     const c = asin(a);
 
-    try testing.expect(math.approxEqAbs(f32, c.re, 1.023822, epsilon));
-    try testing.expect(math.approxEqAbs(f32, c.im, 2.452914, epsilon));
+    try testing.expectApproxEqAbs(1.0238227, c.re, epsilon);
+    try testing.expectApproxEqAbs(2.4529128, c.im, epsilon);
 }
diff --git a/lib/std/math/complex/asinh.zig b/lib/std/math/complex/asinh.zig
@@ -12,12 +12,11 @@ pub fn asinh(z: anytype) Complex(@TypeOf(z.re, z.im)) {
     return Complex(T).init(r.im, -r.re);
 }
 
-const epsilon = 0.0001;
-
 test asinh {
+    const epsilon = math.floatEps(f32);
     const a = Complex(f32).init(5, 3);
     const c = asinh(a);
 
-    try testing.expect(math.approxEqAbs(f32, c.re, 2.459831, epsilon));
-    try testing.expect(math.approxEqAbs(f32, c.im, 0.533999, epsilon));
+    try testing.expectApproxEqAbs(2.4598298, c.re, epsilon);
+    try testing.expectApproxEqAbs(0.5339993, c.im, epsilon);
 }
diff --git a/lib/std/math/complex/atan.zig b/lib/std/math/complex/atan.zig
@@ -32,37 +32,22 @@ fn redupif32(x: f32) f32 {
         t -= 0.5;
     }
 
-    const u = @as(f32, @floatFromInt(@as(i32, @intFromFloat(t))));
-    return ((x - u * DP1) - u * DP2) - t * DP3;
+    const u: f32 = @trunc(t);
+    return ((x - u * DP1) - u * DP2) - u * DP3;
 }
 
 fn atan32(z: Complex(f32)) Complex(f32) {
-    const maxnum = 1.0e38;
-
     const x = z.re;
     const y = z.im;
 
-    if ((x == 0.0) and (y > 1.0)) {
-        // overflow
-        return Complex(f32).init(maxnum, maxnum);
-    }
-
     const x2 = x * x;
     var a = 1.0 - x2 - (y * y);
-    if (a == 0.0) {
-        // overflow
-        return Complex(f32).init(maxnum, maxnum);
-    }
 
     var t = 0.5 * math.atan2(2.0 * x, a);
     const w = redupif32(t);
 
     t = y - 1.0;
     a = x2 + t * t;
-    if (a == 0.0) {
-        // overflow
-        return Complex(f32).init(maxnum, maxnum);
-    }
 
     t = y + 1.0;
     a = (x2 + (t * t)) / a;
@@ -81,57 +66,42 @@ fn redupif64(x: f64) f64 {
         t -= 0.5;
     }
 
-    const u = @as(f64, @floatFromInt(@as(i64, @intFromFloat(t))));
-    return ((x - u * DP1) - u * DP2) - t * DP3;
+    const u: f64 = @trunc(t);
+    return ((x - u * DP1) - u * DP2) - u * DP3;
 }
 
 fn atan64(z: Complex(f64)) Complex(f64) {
-    const maxnum = 1.0e308;
-
     const x = z.re;
     const y = z.im;
 
-    if ((x == 0.0) and (y > 1.0)) {
-        // overflow
-        return Complex(f64).init(maxnum, maxnum);
-    }
-
     const x2 = x * x;
     var a = 1.0 - x2 - (y * y);
-    if (a == 0.0) {
-        // overflow
-        return Complex(f64).init(maxnum, maxnum);
-    }
 
     var t = 0.5 * math.atan2(2.0 * x, a);
     const w = redupif64(t);
 
     t = y - 1.0;
     a = x2 + t * t;
-    if (a == 0.0) {
-        // overflow
-        return Complex(f64).init(maxnum, maxnum);
-    }
 
     t = y + 1.0;
     a = (x2 + (t * t)) / a;
     return Complex(f64).init(w, 0.25 * @log(a));
 }
 
-const epsilon = 0.0001;
-
 test atan32 {
+    const epsilon = math.floatEps(f32);
     const a = Complex(f32).init(5, 3);
     const c = atan(a);
 
-    try testing.expect(math.approxEqAbs(f32, c.re, 1.423679, epsilon));
-    try testing.expect(math.approxEqAbs(f32, c.im, 0.086569, epsilon));
+    try testing.expectApproxEqAbs(1.423679, c.re, epsilon);
+    try testing.expectApproxEqAbs(0.086569, c.im, epsilon);
 }
 
 test atan64 {
+    const epsilon = math.floatEps(f64);
     const a = Complex(f64).init(5, 3);
     const c = atan(a);
 
-    try testing.expect(math.approxEqAbs(f64, c.re, 1.423679, epsilon));
-    try testing.expect(math.approxEqAbs(f64, c.im, 0.086569, epsilon));
+    try testing.expectApproxEqAbs(1.4236790442393028, c.re, epsilon);
+    try testing.expectApproxEqAbs(0.08656905917945844, c.im, epsilon);
 }
diff --git a/lib/std/math/complex/atanh.zig b/lib/std/math/complex/atanh.zig
@@ -12,12 +12,11 @@ pub fn atanh(z: anytype) Complex(@TypeOf(z.re, z.im)) {
     return Complex(T).init(r.im, -r.re);
 }
 
-const epsilon = 0.0001;
-
 test atanh {
+    const epsilon = math.floatEps(f32);
     const a = Complex(f32).init(5, 3);
     const c = atanh(a);
 
-    try testing.expect(math.approxEqAbs(f32, c.re, 0.146947, epsilon));
-    try testing.expect(math.approxEqAbs(f32, c.im, 1.480870, epsilon));
+    try testing.expectApproxEqAbs(0.14694665, c.re, epsilon);
+    try testing.expectApproxEqAbs(1.4808695, c.im, epsilon);
 }
diff --git a/lib/std/math/complex/conj.zig b/lib/std/math/complex/conj.zig
@@ -14,5 +14,6 @@ test conj {
     const a = Complex(f32).init(5, 3);
     const c = a.conjugate();
 
-    try testing.expect(c.re == 5 and c.im == -3);
+    try testing.expectEqual(5, c.re);
+    try testing.expectEqual(-3, c.im);
 }
diff --git a/lib/std/math/complex/cos.zig b/lib/std/math/complex/cos.zig
@@ -11,12 +11,11 @@ pub fn cos(z: anytype) Complex(@TypeOf(z.re, z.im)) {
     return cmath.cosh(p);
 }
 
-const epsilon = 0.0001;
-
 test cos {
+    const epsilon = math.floatEps(f32);
     const a = Complex(f32).init(5, 3);
     const c = cos(a);
 
-    try testing.expect(math.approxEqAbs(f32, c.re, 2.855815, epsilon));
-    try testing.expect(math.approxEqAbs(f32, c.im, 9.606383, epsilon));
+    try testing.expectApproxEqAbs(2.8558152, c.re, epsilon);
+    try testing.expectApproxEqAbs(9.606383, c.im, epsilon);
 }
diff --git a/lib/std/math/complex/cosh.zig b/lib/std/math/complex/cosh.zig
@@ -34,7 +34,7 @@ fn cosh32(z: Complex(f32)) Complex(f32) {
 
     if (ix < 0x7f800000 and iy < 0x7f800000) {
         if (iy == 0) {
-            return Complex(f32).init(math.cosh(x), y);
+            return Complex(f32).init(math.cosh(x), x * y);
         }
         // small x: normal case
         if (ix < 0x41100000) {
@@ -45,7 +45,7 @@ fn cosh32(z: Complex(f32)) Complex(f32) {
         if (ix < 0x42b17218) {
             // x < 88.7: exp(|x|) won't overflow
             const h = @exp(@abs(x)) * 0.5;
-            return Complex(f32).init(math.copysign(h, x) * @cos(y), h * @sin(y));
+            return Complex(f32).init(h * @cos(y), math.copysign(h, x) * @sin(y));
         }
         // x < 192.7: scale to avoid overflow
         else if (ix < 0x4340b1e7) {
@@ -68,7 +68,7 @@ fn cosh32(z: Complex(f32)) Complex(f32) {
         if (hx & 0x7fffff == 0) {
             return Complex(f32).init(x * x, math.copysign(@as(f32, 0.0), x) * y);
         }
-        return Complex(f32).init(x, math.copysign(@as(f32, 0.0), (x + x) * y));
+        return Complex(f32).init(x * x, math.copysign(@as(f32, 0.0), (x + x) * y));
     }
 
     if (ix < 0x7f800000 and iy >= 0x7f800000) {
@@ -123,7 +123,7 @@ fn cosh64(z: Complex(f64)) Complex(f64) {
         }
         // x >= 1455: result always overflows
         else {
-            const h = 0x1p1023;
+            const h = 0x1p1023 * x;
             return Complex(f64).init(h * h * @cos(y), h * @sin(y));
         }
     }
@@ -153,20 +153,29 @@ fn cosh64(z: Complex(f64)) Complex(f64) {
     return Complex(f64).init((x * x) * (y - y), (x + x) * (y - y));
 }
 
-const epsilon = 0.0001;
-
 test cosh32 {
+    const epsilon = math.floatEps(f32);
     const a = Complex(f32).init(5, 3);
     const c = cosh(a);
 
-    try testing.expect(math.approxEqAbs(f32, c.re, -73.467300, epsilon));
-    try testing.expect(math.approxEqAbs(f32, c.im, 10.471557, epsilon));
+    try testing.expectApproxEqAbs(-73.467300, c.re, epsilon);
+    try testing.expectApproxEqAbs(10.471557, c.im, epsilon);
 }
 
 test cosh64 {
+    const epsilon = math.floatEps(f64);
     const a = Complex(f64).init(5, 3);
     const c = cosh(a);
 
-    try testing.expect(math.approxEqAbs(f64, c.re, -73.467300, epsilon));
-    try testing.expect(math.approxEqAbs(f64, c.im, 10.471557, epsilon));
+    try testing.expectApproxEqAbs(-73.46729221264526, c.re, epsilon);
+    try testing.expectApproxEqAbs(10.471557674805572, c.im, epsilon);
+}
+
+test "cosh64 musl" {
+    const epsilon = math.floatEps(f64);
+    const a = Complex(f64).init(7.44648873421389e17, 1.6008058402057622e19);
+    const c = cosh(a);
+
+    try testing.expectApproxEqAbs(std.math.inf(f64), c.re, epsilon);
+    try testing.expectApproxEqAbs(std.math.inf(f64), c.im, epsilon);
 }
diff --git a/lib/std/math/complex/log.zig b/lib/std/math/complex/log.zig
@@ -13,12 +13,11 @@ pub fn log(z: anytype) Complex(@TypeOf(z.re, z.im)) {
     return Complex(T).init(@log(r), phi);
 }
 
-const epsilon = 0.0001;
-
 test log {
+    const epsilon = math.floatEps(f32);
     const a = Complex(f32).init(5, 3);
     const c = log(a);
 
-    try testing.expect(math.approxEqAbs(f32, c.re, 1.763180, epsilon));
-    try testing.expect(math.approxEqAbs(f32, c.im, 0.540419, epsilon));
+    try testing.expectApproxEqAbs(1.7631803, c.re, epsilon);
+    try testing.expectApproxEqAbs(0.5404195, c.im, epsilon);
 }
diff --git a/lib/std/math/complex/pow.zig b/lib/std/math/complex/pow.zig
@@ -9,13 +9,12 @@ pub fn pow(z: anytype, s: anytype) Complex(@TypeOf(z.re, z.im, s.re, s.im)) {
     return cmath.exp(cmath.log(z).mul(s));
 }
 
-const epsilon = 0.0001;
-
 test pow {
+    const epsilon = math.floatEps(f32);
     const a = Complex(f32).init(5, 3);
     const b = Complex(f32).init(2.3, -1.3);
     const c = pow(a, b);
 
-    try testing.expect(math.approxEqAbs(f32, c.re, 58.049110, epsilon));
-    try testing.expect(math.approxEqAbs(f32, c.im, -101.003433, epsilon));
+    try testing.expectApproxEqAbs(58.049110, c.re, epsilon);
+    try testing.expectApproxEqAbs(-101.003433, c.im, epsilon);
 }
diff --git a/lib/std/math/complex/proj.zig b/lib/std/math/complex/proj.zig
@@ -19,5 +19,6 @@ test proj {
     const a = Complex(f32).init(5, 3);
     const c = proj(a);
 
-    try testing.expect(c.re == 5 and c.im == 3);
+    try testing.expectEqual(5, c.re);
+    try testing.expectEqual(3, c.im);
 }
diff --git a/lib/std/math/complex/sin.zig b/lib/std/math/complex/sin.zig
@@ -12,12 +12,11 @@ pub fn sin(z: anytype) Complex(@TypeOf(z.re, z.im)) {
     return Complex(T).init(q.im, -q.re);
 }
 
-const epsilon = 0.0001;
-
 test sin {
+    const epsilon = math.floatEps(f32);
     const a = Complex(f32).init(5, 3);
     const c = sin(a);
 
-    try testing.expect(math.approxEqAbs(f32, c.re, -9.654126, epsilon));
-    try testing.expect(math.approxEqAbs(f32, c.im, 2.841692, epsilon));
+    try testing.expectApproxEqAbs(-9.654126, c.re, epsilon);
+    try testing.expectApproxEqAbs(2.8416924, c.im, epsilon);
 }
diff --git a/lib/std/math/complex/sinh.zig b/lib/std/math/complex/sinh.zig
@@ -152,20 +152,20 @@ fn sinh64(z: Complex(f64)) Complex(f64) {
     return Complex(f64).init((x * x) * (y - y), (x + x) * (y - y));
 }
 
-const epsilon = 0.0001;
-
 test sinh32 {
+    const epsilon = math.floatEps(f32);
     const a = Complex(f32).init(5, 3);
     const c = sinh(a);
 
-    try testing.expect(math.approxEqAbs(f32, c.re, -73.460617, epsilon));
-    try testing.expect(math.approxEqAbs(f32, c.im, 10.472508, epsilon));
+    try testing.expectApproxEqAbs(-73.460617, c.re, epsilon);
+    try testing.expectApproxEqAbs(10.472508, c.im, epsilon);
 }
 
 test sinh64 {
+    const epsilon = math.floatEps(f64);
     const a = Complex(f64).init(5, 3);
     const c = sinh(a);
 
-    try testing.expect(math.approxEqAbs(f64, c.re, -73.460617, epsilon));
-    try testing.expect(math.approxEqAbs(f64, c.im, 10.472508, epsilon));
+    try testing.expectApproxEqAbs(-73.46062169567367, c.re, epsilon);
+    try testing.expectApproxEqAbs(10.472508533940392, c.im, epsilon);
 }