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Diffstat (limited to 'v_windows/v/old/vlib/builtin/float.v')
-rw-r--r-- | v_windows/v/old/vlib/builtin/float.v | 205 |
1 files changed, 205 insertions, 0 deletions
diff --git a/v_windows/v/old/vlib/builtin/float.v b/v_windows/v/old/vlib/builtin/float.v new file mode 100644 index 0000000..99fe8b8 --- /dev/null +++ b/v_windows/v/old/vlib/builtin/float.v @@ -0,0 +1,205 @@ +// 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 builtin + +import strconv + +#include <float.h> +/* +----------------------------------- +----- f64 to string functions ----- +*/ +// str return a `f64` as `string` in suitable notation. +[inline] +pub fn (x f64) str() string { + unsafe { + f := strconv.Float64u{ + f: x + } + if f.u == strconv.double_minus_zero { + return '-0' + } + if f.u == strconv.double_plus_zero { + return '0' + } + } + abs_x := f64_abs(x) + if abs_x >= 0.0001 && abs_x < 1.0e6 { + return strconv.f64_to_str_l(x) + } else { + return strconv.ftoa_64(x) + } +} + +// strg return a `f64` as `string` in "g" printf format +[inline] +pub fn (x f64) strg() string { + if x == 0 { + return '0' + } + abs_x := f64_abs(x) + if abs_x >= 0.0001 && abs_x < 1.0e6 { + return strconv.f64_to_str_l_no_dot(x) + } else { + return strconv.ftoa_64(x) + } +} + +// str returns the value of the `float_literal` as a `string`. +[inline] +pub fn (d float_literal) str() string { + return f64(d).str() +} + +// strsci returns the `f64` as a `string` in scientific notation with `digit_num` decimals displayed, max 17 digits. +// Example: assert f64(1.234).strsci(3) == '1.234e+00' +[inline] +pub fn (x f64) strsci(digit_num int) string { + mut n_digit := digit_num + if n_digit < 1 { + n_digit = 1 + } else if n_digit > 17 { + n_digit = 17 + } + return strconv.f64_to_str(x, n_digit) +} + +// strlong returns a decimal notation of the `f64` as a `string`. +// Example: assert f64(1.23456).strlong() == '1.23456' +[inline] +pub fn (x f64) strlong() string { + return strconv.f64_to_str_l(x) +} + +/* +----------------------------------- +----- f32 to string functions ----- +*/ +// str returns a `f32` as `string` in suitable notation. +[inline] +pub fn (x f32) str() string { + unsafe { + f := strconv.Float32u{ + f: x + } + if f.u == strconv.single_minus_zero { + return '-0' + } + if f.u == strconv.single_plus_zero { + return '0' + } + } + abs_x := f32_abs(x) + if abs_x >= 0.0001 && abs_x < 1.0e6 { + return strconv.f32_to_str_l(x) + } else { + return strconv.ftoa_32(x) + } +} + +// strg return a `f32` as `string` in "g" printf format +[inline] +pub fn (x f32) strg() string { + if x == 0 { + return '0' + } + abs_x := f32_abs(x) + if abs_x >= 0.0001 && abs_x < 1.0e6 { + return strconv.f32_to_str_l_no_dot(x) + } else { + return strconv.ftoa_32(x) + } +} + +// strsci returns the `f32` as a `string` in scientific notation with `digit_num` deciamals displayed, max 8 digits. +// Example: assert f32(1.234).strsci(3) == '1.234e+00' +[inline] +pub fn (x f32) strsci(digit_num int) string { + mut n_digit := digit_num + if n_digit < 1 { + n_digit = 1 + } else if n_digit > 8 { + n_digit = 8 + } + return strconv.f32_to_str(x, n_digit) +} + +// strlong returns a decimal notation of the `f32` as a `string`. +[inline] +pub fn (x f32) strlong() string { + return strconv.f32_to_str_l(x) +} + +/* +----------------------- +----- C functions ----- +*/ +// f32_abs returns the absolute value of `a` as a `f32` value. +// Example: assert f32_abs(-2.0) == 2.0 +[inline] +pub fn f32_abs(a f32) f32 { + return if a < 0 { -a } else { a } +} + +// f64_abs returns the absolute value of `a` as a `f64` value. +// Example: assert f64_abs(-2.0) == f64(2.0) +[inline] +fn f64_abs(a f64) f64 { + return if a < 0 { -a } else { a } +} + +// f32_max returns the largest `f32` of input `a` and `b`. +// Example: assert f32_max(2.0,3.0) == 3.0 +[inline] +pub fn f32_max(a f32, b f32) f32 { + return if a > b { a } else { b } +} + +// f32_min returns the smallest `f32` of input `a` and `b`. +// Example: assert f32_min(2.0,3.0) == 2.0 +[inline] +pub fn f32_min(a f32, b f32) f32 { + return if a < b { a } else { b } +} + +// f64_max returns the largest `f64` of input `a` and `b`. +// Example: assert f64_max(2.0,3.0) == 3.0 +[inline] +pub fn f64_max(a f64, b f64) f64 { + return if a > b { a } else { b } +} + +// f64_min returns the smallest `f64` of input `a` and `b`. +// Example: assert f64_min(2.0,3.0) == 2.0 +[inline] +fn f64_min(a f64, b f64) f64 { + return if a < b { a } else { b } +} + +// eq_epsilon returns true if the `f32` is equal to input `b`. +// using an epsilon of typically 1E-5 or higher (backend/compiler dependent). +// Example: assert f32(2.0).eq_epsilon(2.0) +[inline] +pub fn (a f32) eq_epsilon(b f32) bool { + hi := f32_max(f32_abs(a), f32_abs(b)) + delta := f32_abs(a - b) + if hi > f32(1.0) { + return delta <= hi * (4 * f32(C.FLT_EPSILON)) + } else { + return (1 / (4 * f32(C.FLT_EPSILON))) * delta <= hi + } +} + +// eq_epsilon returns true if the `f64` is equal to input `b`. +// using an epsilon of typically 1E-9 or higher (backend/compiler dependent). +// Example: assert f64(2.0).eq_epsilon(2.0) +[inline] +pub fn (a f64) eq_epsilon(b f64) bool { + hi := f64_max(f64_abs(a), f64_abs(b)) + delta := f64_abs(a - b) + if hi > 1.0 { + return delta <= hi * (4 * f64(C.DBL_EPSILON)) + } else { + return (1 / (4 * f64(C.DBL_EPSILON))) * delta <= hi + } +} |