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authorAndrea Orru <andrea@orru.io>2018-08-06 01:43:19 -0400
committerAndrea Orru <andrea@orru.io>2018-08-06 01:43:19 -0400
commitd2f5e57b68da0b16e5789ca19045ccbcb4ecfa8d (patch)
treee9fa3caec533a0d1e2b434868b2fde1f9240e5c8 /std/math/log10.zig
parent06614b3fa09954464c2e2f32756cacedc178a282 (diff)
parent63a23e848a62d5f167f8d5478de9766cb24aa6eb (diff)
downloadzig-d2f5e57b68da0b16e5789ca19045ccbcb4ecfa8d.tar.gz
zig-d2f5e57b68da0b16e5789ca19045ccbcb4ecfa8d.zip
Merge branch 'master' into zen_stdlib
Diffstat (limited to 'std/math/log10.zig')
-rw-r--r--std/math/log10.zig36
1 files changed, 17 insertions, 19 deletions
diff --git a/std/math/log10.zig b/std/math/log10.zig
index aa74caa901..a93ce48fb7 100644
--- a/std/math/log10.zig
+++ b/std/math/log10.zig
@@ -14,7 +14,7 @@ const TypeId = builtin.TypeId;
pub fn log10(x: var) @typeOf(x) {
const T = @typeOf(x);
switch (@typeId(T)) {
- TypeId.FloatLiteral => {
+ TypeId.ComptimeFloat => {
return @typeOf(1.0)(log10_64(x));
},
TypeId.Float => {
@@ -24,21 +24,21 @@ pub fn log10(x: var) @typeOf(x) {
else => @compileError("log10 not implemented for " ++ @typeName(T)),
};
},
- TypeId.IntLiteral => {
+ TypeId.ComptimeInt => {
return @typeOf(1)(math.floor(log10_64(f64(x))));
},
TypeId.Int => {
- return T(math.floor(log10_64(f64(x))));
+ return @floatToInt(T, math.floor(log10_64(@intToFloat(f64, x))));
},
else => @compileError("log10 not implemented for " ++ @typeName(T)),
}
}
pub fn log10_32(x_: f32) f32 {
- const ivln10hi: f32 = 4.3432617188e-01;
- const ivln10lo: f32 = -3.1689971365e-05;
- const log10_2hi: f32 = 3.0102920532e-01;
- const log10_2lo: f32 = 7.9034151668e-07;
+ const ivln10hi: f32 = 4.3432617188e-01;
+ const ivln10lo: f32 = -3.1689971365e-05;
+ const log10_2hi: f32 = 3.0102920532e-01;
+ const log10_2lo: f32 = 7.9034151668e-07;
const Lg1: f32 = 0xaaaaaa.0p-24;
const Lg2: f32 = 0xccce13.0p-25;
const Lg3: f32 = 0x91e9ee.0p-25;
@@ -71,7 +71,7 @@ pub fn log10_32(x_: f32) f32 {
// x into [sqrt(2) / 2, sqrt(2)]
ix += 0x3F800000 - 0x3F3504F3;
- k += i32(ix >> 23) - 0x7F;
+ k += @intCast(i32, ix >> 23) - 0x7F;
ix = (ix & 0x007FFFFF) + 0x3F3504F3;
x = @bitCast(f32, ix);
@@ -89,14 +89,14 @@ pub fn log10_32(x_: f32) f32 {
u &= 0xFFFFF000;
hi = @bitCast(f32, u);
const lo = f - hi - hfsq + s * (hfsq + R);
- const dk = f32(k);
+ const dk = @intToFloat(f32, k);
return dk * log10_2lo + (lo + hi) * ivln10lo + lo * ivln10hi + hi * ivln10hi + dk * log10_2hi;
}
pub fn log10_64(x_: f64) f64 {
- const ivln10hi: f64 = 4.34294481878168880939e-01;
- const ivln10lo: f64 = 2.50829467116452752298e-11;
+ const ivln10hi: f64 = 4.34294481878168880939e-01;
+ const ivln10lo: f64 = 2.50829467116452752298e-11;
const log10_2hi: f64 = 3.01029995663611771306e-01;
const log10_2lo: f64 = 3.69423907715893078616e-13;
const Lg1: f64 = 6.666666666666735130e-01;
@@ -109,7 +109,7 @@ pub fn log10_64(x_: f64) f64 {
var x = x_;
var ix = @bitCast(u64, x);
- var hx = u32(ix >> 32);
+ var hx = @intCast(u32, ix >> 32);
var k: i32 = 0;
if (hx < 0x00100000 or hx >> 31 != 0) {
@@ -125,18 +125,16 @@ pub fn log10_64(x_: f64) f64 {
// subnormal, scale x
k -= 54;
x *= 0x1.0p54;
- hx = u32(@bitCast(u64, x) >> 32);
- }
- else if (hx >= 0x7FF00000) {
+ hx = @intCast(u32, @bitCast(u64, x) >> 32);
+ } else if (hx >= 0x7FF00000) {
return x;
- }
- else if (hx == 0x3FF00000 and ix << 32 == 0) {
+ } else if (hx == 0x3FF00000 and ix << 32 == 0) {
return 0;
}
// x into [sqrt(2) / 2, sqrt(2)]
hx += 0x3FF00000 - 0x3FE6A09E;
- k += i32(hx >> 20) - 0x3FF;
+ k += @intCast(i32, hx >> 20) - 0x3FF;
hx = (hx & 0x000FFFFF) + 0x3FE6A09E;
ix = (u64(hx) << 32) | (ix & 0xFFFFFFFF);
x = @bitCast(f64, ix);
@@ -159,7 +157,7 @@ pub fn log10_64(x_: f64) f64 {
// val_hi + val_lo ~ log10(1 + f) + k * log10(2)
var val_hi = hi * ivln10hi;
- const dk = f64(k);
+ const dk = @intToFloat(f64, k);
const y = dk * log10_2hi;
var val_lo = dk * log10_2lo + (lo + hi) * ivln10lo + lo * ivln10hi;