mirror of https://github.com/tinygo-org/tinygo.git
wasmstm32webassemblymicrocontrollerarmavrspiwasiadafruitarduinocircuitplayground-expressgpioi2cllvmmicrobitnrf51nrf52nrf52840samd21tinygo
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
66 lines
1.7 KiB
66 lines
1.7 KiB
6 years ago
|
// Copyright 2010 The Go Authors. All rights reserved.
|
||
|
|
// Use of this source code is governed by a BSD-style
|
||
|
|
// license that can be found in the LICENSE file.
|
||
|
|
|
||
|
|
package runtime
|
||
|
|
|
||
|
|
// inf2one returns a signed 1 if f is an infinity and a signed 0 otherwise.
|
||
|
|
// The sign of the result is the sign of f.
|
||
|
|
func inf2one(f float64) float64 {
|
||
|
|
g := 0.0
|
||
|
|
if isInf(f) {
|
||
|
|
g = 1.0
|
||
|
|
}
|
||
|
|
return copysign(g, f)
|
||
|
|
}
|
||
|
|
|
||
|
|
func complex64div(n complex64, m complex64) complex64 {
|
||
|
|
return complex64(complex128div(complex128(n), complex128(m)))
|
||
|
|
}
|
||
|
|
|
||
|
|
func complex128div(n complex128, m complex128) complex128 {
|
||
|
|
var e, f float64 // complex(e, f) = n/m
|
||
|
|
|
||
|
|
// Algorithm for robust complex division as described in
|
||
|
|
// Robert L. Smith: Algorithm 116: Complex division. Commun. ACM 5(8): 435 (1962).
|
||
|
|
if abs(real(m)) >= abs(imag(m)) {
|
||
|
|
ratio := imag(m) / real(m)
|
||
|
|
denom := real(m) + ratio*imag(m)
|
||
|
|
e = (real(n) + imag(n)*ratio) / denom
|
||
|
|
f = (imag(n) - real(n)*ratio) / denom
|
||
|
|
} else {
|
||
|
|
ratio := real(m) / imag(m)
|
||
|
|
denom := imag(m) + ratio*real(m)
|
||
|
|
e = (real(n)*ratio + imag(n)) / denom
|
||
|
|
f = (imag(n)*ratio - real(n)) / denom
|
||
|
|
}
|
||
|
|
|
||
|
|
if isNaN(e) && isNaN(f) {
|
||
|
|
// Correct final result to infinities and zeros if applicable.
|
||
|
|
// Matches C99: ISO/IEC 9899:1999 - G.5.1 Multiplicative operators.
|
||
|
|
|
||
|
|
a, b := real(n), imag(n)
|
||
|
|
c, d := real(m), imag(m)
|
||
|
|
|
||
|
|
switch {
|
||
|
|
case m == 0 && (!isNaN(a) || !isNaN(b)):
|
||
|
|
e = copysign(inf, c) * a
|
||
|
|
f = copysign(inf, c) * b
|
||
|
|
|
||
|
|
case (isInf(a) || isInf(b)) && isFinite(c) && isFinite(d):
|
||
|
|
a = inf2one(a)
|
||
|
|
b = inf2one(b)
|
||
|
|
e = inf * (a*c + b*d)
|
||
|
|
f = inf * (b*c - a*d)
|
||
|
|
|
||
|
|
case (isInf(c) || isInf(d)) && isFinite(a) && isFinite(b):
|
||
|
|
c = inf2one(c)
|
||
|
|
d = inf2one(d)
|
||
|
|
e = 0 * (a*c + b*d)
|
||
|
|
f = 0 * (b*c - a*d)
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
return complex(e, f)
|
||
|
|
}
|