130 lines
2.9 KiB
V
130 lines
2.9 KiB
V
// Copyright (c) 2019-2020 Alexander Medvednikov. All rights reserved.
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// Use of this source code is governed by an MIT license
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// that can be found in the LICENSE file.
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module math
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// NOTE
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// When adding a new function, please make sure it's in the right place.
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// All functions are sorted alphabetically, separated by wrapped functions vs
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// backend specific functions.
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// If using System/Backend dependent functions, put them in their respective
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// .c.v or .js.v or other files
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// Below are functions that are not wrappers for built-in system functions, but
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// native V functions. They are still sorted alphabetically
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// Faster approximate sin() and cos() implemented from lolremez
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pub fn aprox_sin(a f64) f64 {
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a0 := 1.91059300966915117e-31
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a1 := 1.00086760103908896
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a2 := -1.21276126894734565e-2
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a3 := -1.38078780785773762e-1
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a4 := -2.67353392911981221e-2
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a5 := 2.08026600266304389e-2
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a6 := -3.03996055049204407e-3
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a7 := 1.38235642404333740e-4
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return a0 + a * (a1 + a * (a2 + a * (a3 + a * (a4 + a * (a5 + a * (a6 + a * a7))))))
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}
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pub fn aprox_cos(a f64) f64 {
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a0 := 9.9995999154986614e-1
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a1 := 1.2548995793001028e-3
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a2 := -5.0648546280678015e-1
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a3 := 1.2942246466519995e-2
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a4 := 2.8668384702547972e-2
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a5 := 7.3726485210586547e-3
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a6 := -3.8510875386947414e-3
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a7 := 4.7196604604366623e-4
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a8 := -1.8776444013090451e-5
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return a0 + a * (a1 + a * (a2 + a * (a3 + a * (a4 + a * (a5 + a * (a6 + a * (a7 + a * a8)))))))
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}
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// copysign returns a value with the magnitude of x and the sign of y
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pub fn copysign(x, y f64) f64 {
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return f64_from_bits((f64_bits(x) & ~sign_mask) | (f64_bits(y) & sign_mask))
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}
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// degrees convert from degrees to radians.
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pub fn degrees(radians f64) f64 {
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return radians * (180.0 / pi)
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}
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// digits returns an array of the digits of n in the given base.
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pub fn digits(_n, base int) []int {
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if base < 2 {
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panic('digits: Cannot find digits of n with base $base')
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}
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mut n := _n
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mut sign := 1
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if n < 0 {
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sign = -1
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n = -n
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}
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mut res := []int{}
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for n != 0 {
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res << (n % base) * sign
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n /= base
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}
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return res
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}
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pub fn fabs(x f64) f64 {
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if x < 0.0 {
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return -x
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}
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return x
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}
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// gcd calculates greatest common (positive) divisor (or zero if a and b are both zero).
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pub fn gcd(a_, b_ i64) i64 {
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mut a := a_
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mut b := b_
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if a < 0 {
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a = -a
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}
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if b < 0 {
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b = -b
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}
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for b != 0 {
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a %= b
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if a == 0 {
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return b
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}
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b %= a
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}
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return a
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}
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// lcm calculates least common (non-negative) multiple.
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pub fn lcm(a, b i64) i64 {
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if a == 0 {
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return a
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}
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res := a * (b / gcd(b, a))
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if res < 0 {
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return -res
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}
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return res
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}
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// max returns the maximum value of the two provided.
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pub fn max(a, b f64) f64 {
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if a > b {
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return a
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}
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return b
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}
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// min returns the minimum value of the two provided.
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pub fn min(a, b f64) f64 {
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if a < b {
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return a
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}
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return b
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}
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// radians convert from radians to degrees.
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pub fn radians(degrees f64) f64 {
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return degrees * (pi / 180.0)
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}
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