math: add a pure V math.mathutil, with generic min, max and abs functions (#9176), and use it consistently

vlib/math/util/util.v

@@ -0,0 +1,82 @@
+// Copyright (c) 2019-2021 Alexander Medvednikov. All rights reserved.
+// Use of this source code is governed by an MIT license
+// that can be found in the LICENSE file.
+module util
+
+// imin returns the smallest of two integer values
+[inline]
+pub fn imin(a int, b int) int {
+	return if a < b { a } else { b }
+}
+
+// imin returns the biggest of two integer values
+[inline]
+pub fn imax(a int, b int) int {
+	return if a > b { a } else { b }
+}
+
+// iabs returns an integer as absolute value
+[inline]
+pub fn iabs(v int) int {
+	return if v > 0 { v } else { -v }
+}
+
+// umin returns the smallest of two u32 values
+[inline]
+pub fn umin(a u32, b u32) u32 {
+	return if a < b { a } else { b }
+}
+
+// umax returns the biggest of two u32 values
+[inline]
+pub fn umax(a u32, b u32) u32 {
+	return if a > b { a } else { b }
+}
+
+// uabs returns an u32 as absolute value
+[inline]
+pub fn uabs(v u32) u32 {
+	return if v > 0 { v } else { -v }
+}
+
+// fmin_32 returns the smallest `f32` of input `a` and `b`.
+// Example: assert fmin_32(2.0,3.0) == 2.0
+[inline]
+pub fn fmin_32(a f32, b f32) f32 {
+	return if a < b { a } else { b }
+}
+
+// fmax_32 returns the largest `f32` of input `a` and `b`.
+// Example: assert fmax_32(2.0,3.0) == 3.0
+[inline]
+pub fn fmax_32(a f32, b f32) f32 {
+	return if a > b { a } else { b }
+}
+
+// fabs_32 returns the absolute value of `a` as a `f32` value.
+// Example: assert fabs_32(-2.0) == 2.0
+[inline]
+pub fn fabs_32(v f32) f32 {
+	return if v > 0 { v } else { -v }
+}
+
+// fmin_64 returns the smallest `f64` of input `a` and `b`.
+// Example: assert fmin_64(2.0,3.0) == 2.0
+[inline]
+pub fn fmin_64(a f64, b f64) f64 {
+	return if a < b { a } else { b }
+}
+
+// fmax_64 returns the largest `f64` of input `a` and `b`.
+// Example: assert fmax_64(2.0,3.0) == 3.0
+[inline]
+pub fn fmax_64(a f64, b f64) f64 {
+	return if a > b { a } else { b }
+}
+
+// fabs_64 returns the absolute value of `a` as a `f64` value.
+// Example: assert fabs_64(-2.0) == f64(2.0)
+[inline]
+pub fn fabs_64(v f64) f64 {
+	return if v > 0 { v } else { -v }
+}