diff options
| -rw-r--r-- | changelog.md | 1 | ||||
| -rw-r--r-- | compiler/vmops.nim | 6 | ||||
| -rw-r--r-- | lib/pure/math.nim | 38 | ||||
| -rw-r--r-- | tests/stdlib/tmath.nim | 50 |
4 files changed, 94 insertions, 1 deletions
diff --git a/changelog.md b/changelog.md index 035ba46b8..bbc83ff25 100644 --- a/changelog.md +++ b/changelog.md @@ -69,6 +69,7 @@ - `echo` and `debugEcho` will now raise `IOError` if writing to stdout fails. Previous behavior silently ignored errors. See #16366. Use `-d:nimLegacyEchoNoRaise` for previous behavior. +- Added `math.copySign`. - Added new operations for singly- and doubly linked lists: `lists.toSinglyLinkedList` and `lists.toDoublyLinkedList` convert from `openArray`s; `lists.copy` implements shallow copying; `lists.add` concatenates two lists - an O(1) variation that consumes diff --git a/compiler/vmops.nim b/compiler/vmops.nim index 47df3d24f..3e859d3d7 100644 --- a/compiler/vmops.nim +++ b/compiler/vmops.nim @@ -13,6 +13,9 @@ from math import sqrt, ln, log10, log2, exp, round, arccos, arcsin, arctan, arctan2, cos, cosh, hypot, sinh, sin, tan, tanh, pow, trunc, floor, ceil, `mod` +when declared(math.copySign): + from math import copySign + from os import getEnv, existsEnv, dirExists, fileExists, putEnv, walkDir, getAppFilename from md5 import getMD5 from sighashes import symBodyDigest @@ -168,6 +171,9 @@ proc registerAdditionalOps*(c: PCtx) = wrap1f_math(floor) wrap1f_math(ceil) + when declared(copySign): + wrap2f_math(copySign) + wrap1s(getMD5, md5op) proc `mod Wrapper`(a: VmArgs) {.nimcall.} = diff --git a/lib/pure/math.nim b/lib/pure/math.nim index 5b19a8ec0..76052ec3b 100644 --- a/lib/pure/math.nim +++ b/lib/pure/math.nim @@ -62,6 +62,9 @@ when defined(c) or defined(cpp): proc c_isnan(x: float): bool {.importc: "isnan", header: "<math.h>".} # a generic like `x: SomeFloat` might work too if this is implemented via a C macro. + proc c_copysign(x, y: cfloat): cfloat {.importc: "copysignf", header: "<math.h>".} + proc c_copysign(x, y: cdouble): cdouble {.importc: "copysign", header: "<math.h>".} + func binom*(n, k: int): int = ## Computes the `binomial coefficient <https://en.wikipedia.org/wiki/Binomial_coefficient>`_. runnableExamples: @@ -153,6 +156,40 @@ func isNaN*(x: SomeFloat): bool {.inline, since: (1,5,1).} = when defined(js): fn() else: result = c_isnan(x) +func copySign*[T: SomeFloat](x, y: T): T {.inline, since: (1, 5, 1).} = + ## Returns a value with the magnitude of `x` and the sign of `y`; + ## this works even if x or y are NaN or zero, both of which can carry a sign. + runnableExamples: + doAssert copySign(1.0, -0.0) == -1.0 + doAssert copySign(0.0, -0.0) == -0.0 + doAssert copySign(-1.0, 0.0) == 1.0 + doAssert copySign(10.0, 0.0) == 10.0 + + doAssert copySign(Inf, -1.0) == -Inf + doAssert copySign(-Inf, 1.0) == Inf + doAssert copySign(-1.0, NaN) == 1.0 + doAssert copySign(10.0, NaN) == 10.0 + + doAssert copySign(NaN, 0.0).isNaN + doAssert copySign(NaN, -0.0).isNaN + + # fails in VM and JS backend + doAssert copySign(1.0, copySign(NaN, -1.0)) == -1.0 + + # TODO use signbit for examples + template impl() = + if y > 0.0 or (y == 0.0 and 1.0 / y > 0.0): + result = abs(x) + elif y <= 0.0: + result = -abs(x) + else: # must be NaN + result = abs(x) + + when defined(js): impl() + else: + when nimvm: impl() + else: result = c_copysign(x, y) + func classify*(x: float): FloatClass = ## Classifies a floating point value. ## @@ -1159,3 +1196,4 @@ func lcm*[T](x: openArray[T]): T {.since: (1, 1).} = while i < x.len: result = lcm(result, x[i]) inc(i) + diff --git a/tests/stdlib/tmath.nim b/tests/stdlib/tmath.nim index 64a4ff0ca..1b6fb4e9f 100644 --- a/tests/stdlib/tmath.nim +++ b/tests/stdlib/tmath.nim @@ -308,5 +308,53 @@ template main = doAssert not Inf.isNaN doAssert isNaN(Inf - Inf) -main() + block: # copySign + doAssert copySign(10.0, -1.0) == -10.0 + doAssert copySign(-10.0, -1.0) == -10.0 + doAssert copySign(-10.0, 1.0) == 10.0 + doAssert copySign(float(10), -1.0) == -10.0 + + doAssert copySign(10.0'f64, -1.0) == -10.0 + doAssert copySign(-10.0'f64, -1.0) == -10.0 + doAssert copySign(-10.0'f64, 1.0) == 10.0 + doAssert copySign(10'f64, -1.0) == -10.0 + + doAssert copySign(10.0'f32, -1.0) == -10.0 + doAssert copySign(-10.0'f32, -1.0) == -10.0 + doAssert copySign(-10.0'f32, 1.0) == 10.0 + doAssert copySign(10'f32, -1.0) == -10.0 + + doAssert copySign(Inf, -1.0) == -Inf + doAssert copySign(-Inf, 1.0) == Inf + doAssert copySign(Inf, 1.0) == Inf + doAssert copySign(-Inf, -1.0) == -Inf + doAssert copySign(Inf, 0.0) == Inf + doAssert copySign(Inf, -0.0) == -Inf + doAssert copySign(-Inf, 0.0) == Inf + doAssert copySign(-Inf, -0.0) == -Inf + doAssert copySign(1.0, -0.0) == -1.0 + doAssert copySign(0.0, -0.0) == -0.0 + doAssert copySign(-1.0, 0.0) == 1.0 + doAssert copySign(10.0, 0.0) == 10.0 + doAssert copySign(-1.0, NaN) == 1.0 + doAssert copySign(10.0, NaN) == 10.0 + + doAssert copySign(NaN, NaN).isNaN + doAssert copySign(-NaN, NaN).isNaN + doAssert copySign(NaN, -NaN).isNaN + doAssert copySign(-NaN, -NaN).isNaN + doAssert copySign(NaN, 0.0).isNaN + doAssert copySign(NaN, -0.0).isNaN + doAssert copySign(-NaN, 0.0).isNaN + doAssert copySign(-NaN, -0.0).isNaN + + when nimvm: + discard + else: + when not defined(js): + doAssert copySign(-1.0, -NaN) == 1.0 + doAssert copySign(10.0, -NaN) == 10.0 + doAssert copySign(1.0, copySign(NaN, -1.0)) == -1.0 # fails in VM + static: main() +main() |