From 5fe21c3e2b88e8248c79311401db03124e88bc52 Mon Sep 17 00:00:00 2001 From: Charles Karney Date: Tue, 17 Sep 2019 10:29:53 -0400 Subject: Add atanh, copysign, cbrt, remainder, remquo to math.cpp. The supported C99 math functions provided by math.cpp are thus hypot log1p asinh atanh copysign cbrt remainder remquo round lround Make compiler checks in CMakeLists.txt and configure.ac consistent with this set. Make geodesic.c use the math.cpp defined (instead of the internally defined) versions of hypot atanh copysign cbrt This is keyed off the presence of the PROJ_LIB macro. I had at one time https://github.com/OSGeo/PROJ/pull/1425 suggested supplying an additional macro PROJ_COMPILATION when compiling geodesic.c. However, PROJ_LIB seems to fill the bill OK. The *next* version of geodesic.c (due out in a few weeks) will also use remainder remquo All of this is only of concern for C compilers without C99 support. So this may become an historical footnote at some point. --- src/math.cpp | 131 ++++++++++++++++++++++++++++++++++++++++++++++------------- 1 file changed, 102 insertions(+), 29 deletions(-) (limited to 'src/math.cpp') diff --git a/src/math.cpp b/src/math.cpp index 540ab9eb..0ec4f57f 100644 --- a/src/math.cpp +++ b/src/math.cpp @@ -44,64 +44,137 @@ int pj_isnan (double x) { #if !(defined(HAVE_C99_MATH) && HAVE_C99_MATH) +/* Define C99 compatible versions of + * hypot + * log1p + * asinh + * atanh + * copysign + * cbrt + * remainder + * remquo + * round + * lround + */ + /* Compute hypotenuse */ double pj_hypot(double x, double y) { - x = fabs(x); - y = fabs(y); - if ( x < y ) { - x /= y; - return ( y * sqrt( 1. + x * x ) ); - } else { - y /= (x != 0.0 ? x : 1.0); - return ( x * sqrt( 1. + y * y ) ); - } + x = fabs(x); + y = fabs(y); + if (x < y) { + x /= y; /* y is nonzero */ + return y * sqrt(1 + x * x); + } else { + y /= (x ? x : 1); + return x * sqrt(1 + y * y); + } } /* Compute log(1+x) accurately */ double pj_log1p(double x) { - volatile double - y = 1 + x, - z = y - 1; - /* Here's the explanation for this magic: y = 1 + z, exactly, and z - * approx x, thus log(y)/z (which is nearly constant near z = 0) returns - * a good approximation to the true log(1 + x)/x. The multiplication x * - * (log(y)/z) introduces little additional error. */ - return z == 0 ? x : x * log(y) / z; + volatile double + y = 1 + x, + z = y - 1; + /* Here's the explanation for this magic: y = 1 + z, exactly, and z + * approx x, thus log(y)/z (which is nearly constant near z = 0) returns + * a good approximation to the true log(1 + x)/x. The multiplication x * + * (log(y)/z) introduces little additional error. */ + return z == 0 ? x : x * log(y) / z; } /* Compute asinh(x) accurately */ double pj_asinh(double x) { - double y = fabs(x); /* Enforce odd parity */ - y = log1p(y * (1 + y/(hypot(1.0, y) + 1))); - return x > 0 ? y : (x < 0 ? -y : x); + double y = fabs(x); /* Enforce odd parity */ + y = pj_log1p(y * (1 + y/(pj_hypot(1.0, y) + 1))); + return x > 0 ? y : (x < 0 ? -y : x); /* asinh(-0.0) = -0.0 */ +} + +/* Compute atanh(x) accurately */ +double pj_atanh(double x) { + double y = fabs(x); /* Enforce odd parity */ + y = pj_log1p(2 * y/(1 - y))/2; + return x > 0 ? y : (x < 0 ? -y : x); /* atanh(-0.0) = -0.0 */ +} + +/* Implement copysign(x, y) */ +double pj_copysign(double x, double y) { + /* 1/y trick to get the sign of -0.0 */ + return fabs(x) * (y < 0 || (y == 0 && 1/y < 0) ? -1 : 1); +} + +/* Implement cbrt(x) */ +double pj_cbrt(double x) { + double y = pow(fabs(x), 1/3.0); /* Return the real cube root */ + return x > 0 ? y : (x < 0 ? -y : x); /* cbrt(-0.0) = -0.0 */ +} + +/* Implement remainder(x, y) with ties to even */ +double pj_remainder(double x, double y) { + double z; + y = fabs(y); /* The result doesn't depend on the sign of y */ + z = fmod(x, y); + if (z == 0) + /* This shouldn't be necessary. However, before version 14 (2015), + * Visual Studio had problems dealing with -0.0. Specifically + * VC 10,11,12 and 32-bit compile: fmod(-0.0, 360.0) -> +0.0 + * python 2.7 on Windows 32-bit machines has the same problem. */ + z = pj_copysign(z, x); + else if (2 * fabs(z) == y) + z -= fmod(x, 2 * y) - z; /* Implement ties to even */ + else if (2 * fabs(z) > y) + z += (z < 0 ? y : -y); /* Fold remaining cases to (-y/2, y/2) */ + return z; +} + +/* Implement remquo(x, y, n) with n giving low 3 bits + sign of x/y */ +double pj_remquo(double x, double y, int* n) { + double z = pj_remainder(x, y); + if (n) { + double + a = pj_remainder(x, 2 * y), + b = pj_remainder(x, 4 * y), + c = pj_remainder(x, 8 * y); + *n = (a > z ? 1 : (a < z ? -1 : 0)); + *n += (b > a ? 2 : (b < a ? -2 : 0)); + *n += (c > b ? 4 : (c < b ? -4 : 0)); + if (y < 0) *n *= -1; + if (y != 0) { + if (x/y > 0 && *n <= 0) + *n += 8; + else if (x/y < 0 && *n >= 0) + *n -= 8; + } + } + return z; } +/* Implement round(x) */ double pj_round(double x) { /* The handling of corner cases is copied from boost; see * https://github.com/boostorg/math/pull/8 * with improvements to return -0.0 when appropriate */ double t; - if (x == 0) - return x; /* Retain sign of 0 */ - else if (0 < x && x < 0.5) + if (0 < x && x < 0.5) return +0.0; else if (0 > x && x > -0.5) return -0.0; - else if (x > 0) { + else if (x > 0) { t = ceil(x); return 0.5 < t - x ? t - 1 : t; - } else { /* Includes NaN */ + } else if (x < 0) { t = floor(x); return 0.5 < x - t ? t + 1 : t; - } + } else /* +/-0 and NaN */ + return x; /* retain sign of 0 */ } +/* Implement lround(x) */ long pj_lround(double x) { /* Default value for overflow + NaN + (x == LONG_MIN) */ long r = LONG_MIN; - x = round(x); - if (fabs(x) < -(double)LONG_MIN) /* Assume (double)LONG_MIN is exact */ - r = (int)x; + x = pj_round(x); + if (fabs(x) < -(double)r) /* Assume (double)LONG_MIN is exact */ + r = (long)x; return r; } -- cgit v1.2.3 From c080801637b5b3c1fe7462829411a6859ce581dd Mon Sep 17 00:00:00 2001 From: Charles Karney Date: Tue, 17 Sep 2019 11:50:45 -0400 Subject: Fix floating-point number into integer warning in math.cpp --- src/math.cpp | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'src/math.cpp') diff --git a/src/math.cpp b/src/math.cpp index 0ec4f57f..6c1b6d1b 100644 --- a/src/math.cpp +++ b/src/math.cpp @@ -65,7 +65,7 @@ double pj_hypot(double x, double y) { x /= y; /* y is nonzero */ return y * sqrt(1 + x * x); } else { - y /= (x ? x : 1); + y /= (x != 0 ? x : 1); return x * sqrt(1 + y * y); } } -- cgit v1.2.3 From 93d0f53db70b581718f29601df11f4b819ef943e Mon Sep 17 00:00:00 2001 From: Charles Karney Date: Wed, 18 Sep 2019 07:08:55 -0400 Subject: Try removing C99 math functions from math.cpp (but leave isnan). --- src/math.cpp | 138 ----------------------------------------------------------- 1 file changed, 138 deletions(-) (limited to 'src/math.cpp') diff --git a/src/math.cpp b/src/math.cpp index 6c1b6d1b..90d35001 100644 --- a/src/math.cpp +++ b/src/math.cpp @@ -41,141 +41,3 @@ int pj_isnan (double x) { /* cppcheck-suppress duplicateExpression */ return x != x; } - -#if !(defined(HAVE_C99_MATH) && HAVE_C99_MATH) - -/* Define C99 compatible versions of - * hypot - * log1p - * asinh - * atanh - * copysign - * cbrt - * remainder - * remquo - * round - * lround - */ - -/* Compute hypotenuse */ -double pj_hypot(double x, double y) { - x = fabs(x); - y = fabs(y); - if (x < y) { - x /= y; /* y is nonzero */ - return y * sqrt(1 + x * x); - } else { - y /= (x != 0 ? x : 1); - return x * sqrt(1 + y * y); - } -} - -/* Compute log(1+x) accurately */ -double pj_log1p(double x) { - volatile double - y = 1 + x, - z = y - 1; - /* Here's the explanation for this magic: y = 1 + z, exactly, and z - * approx x, thus log(y)/z (which is nearly constant near z = 0) returns - * a good approximation to the true log(1 + x)/x. The multiplication x * - * (log(y)/z) introduces little additional error. */ - return z == 0 ? x : x * log(y) / z; -} - -/* Compute asinh(x) accurately */ -double pj_asinh(double x) { - double y = fabs(x); /* Enforce odd parity */ - y = pj_log1p(y * (1 + y/(pj_hypot(1.0, y) + 1))); - return x > 0 ? y : (x < 0 ? -y : x); /* asinh(-0.0) = -0.0 */ -} - -/* Compute atanh(x) accurately */ -double pj_atanh(double x) { - double y = fabs(x); /* Enforce odd parity */ - y = pj_log1p(2 * y/(1 - y))/2; - return x > 0 ? y : (x < 0 ? -y : x); /* atanh(-0.0) = -0.0 */ -} - -/* Implement copysign(x, y) */ -double pj_copysign(double x, double y) { - /* 1/y trick to get the sign of -0.0 */ - return fabs(x) * (y < 0 || (y == 0 && 1/y < 0) ? -1 : 1); -} - -/* Implement cbrt(x) */ -double pj_cbrt(double x) { - double y = pow(fabs(x), 1/3.0); /* Return the real cube root */ - return x > 0 ? y : (x < 0 ? -y : x); /* cbrt(-0.0) = -0.0 */ -} - -/* Implement remainder(x, y) with ties to even */ -double pj_remainder(double x, double y) { - double z; - y = fabs(y); /* The result doesn't depend on the sign of y */ - z = fmod(x, y); - if (z == 0) - /* This shouldn't be necessary. However, before version 14 (2015), - * Visual Studio had problems dealing with -0.0. Specifically - * VC 10,11,12 and 32-bit compile: fmod(-0.0, 360.0) -> +0.0 - * python 2.7 on Windows 32-bit machines has the same problem. */ - z = pj_copysign(z, x); - else if (2 * fabs(z) == y) - z -= fmod(x, 2 * y) - z; /* Implement ties to even */ - else if (2 * fabs(z) > y) - z += (z < 0 ? y : -y); /* Fold remaining cases to (-y/2, y/2) */ - return z; -} - -/* Implement remquo(x, y, n) with n giving low 3 bits + sign of x/y */ -double pj_remquo(double x, double y, int* n) { - double z = pj_remainder(x, y); - if (n) { - double - a = pj_remainder(x, 2 * y), - b = pj_remainder(x, 4 * y), - c = pj_remainder(x, 8 * y); - *n = (a > z ? 1 : (a < z ? -1 : 0)); - *n += (b > a ? 2 : (b < a ? -2 : 0)); - *n += (c > b ? 4 : (c < b ? -4 : 0)); - if (y < 0) *n *= -1; - if (y != 0) { - if (x/y > 0 && *n <= 0) - *n += 8; - else if (x/y < 0 && *n >= 0) - *n -= 8; - } - } - return z; -} - -/* Implement round(x) */ -double pj_round(double x) { - /* The handling of corner cases is copied from boost; see - * https://github.com/boostorg/math/pull/8 - * with improvements to return -0.0 when appropriate */ - double t; - if (0 < x && x < 0.5) - return +0.0; - else if (0 > x && x > -0.5) - return -0.0; - else if (x > 0) { - t = ceil(x); - return 0.5 < t - x ? t - 1 : t; - } else if (x < 0) { - t = floor(x); - return 0.5 < x - t ? t + 1 : t; - } else /* +/-0 and NaN */ - return x; /* retain sign of 0 */ -} - -/* Implement lround(x) */ -long pj_lround(double x) { - /* Default value for overflow + NaN + (x == LONG_MIN) */ - long r = LONG_MIN; - x = pj_round(x); - if (fabs(x) < -(double)r) /* Assume (double)LONG_MIN is exact */ - r = (long)x; - return r; -} - -#endif /* !(defined(HAVE_C99_MATH) && HAVE_C99_MATH) */ -- cgit v1.2.3 From 646da7bf3868090ec8ac2d05ab63781de86be64b Mon Sep 17 00:00:00 2001 From: Charles Karney Date: Wed, 18 Sep 2019 14:25:15 -0400 Subject: math.cpp removed since its isnan isn't used. Keep proj_math.h (which just includes math.h and limits.h) since it's included in a score of places. --- src/math.cpp | 43 ------------------------------------------- 1 file changed, 43 deletions(-) delete mode 100644 src/math.cpp (limited to 'src/math.cpp') diff --git a/src/math.cpp b/src/math.cpp deleted file mode 100644 index 90d35001..00000000 --- a/src/math.cpp +++ /dev/null @@ -1,43 +0,0 @@ -/****************************************************************************** - * Project: PROJ - * Purpose: Make C99 math functions available on C89 systems - * Author: Kristian Evers - * - ****************************************************************************** - * Copyright (c) 2018, Kristian Evers - * - * Permission is hereby granted, free of charge, to any person obtaining a - * copy of this software and associated documentation files (the "Software"), - * to deal in the Software without restriction, including without limitation - * the rights to use, copy, modify, merge, publish, distribute, sublicense, - * and/or sell copies of the Software, and to permit persons to whom the - * Software is furnished to do so, subject to the following conditions: - * - * The above copyright notice and this permission notice shall be included - * in all copies or substantial portions of the Software. - * - * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS - * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, - * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL - * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER - * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING - * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER - * DEALINGS IN THE SOFTWARE. - *****************************************************************************/ - -#include "proj_math.h" - -/* pj_isnan is used in gie.c which means that is has to */ -/* be exported in the Windows DLL and therefore needs */ -/* to be declared even though we have isnan() on the */ -/* system. */ - -#ifdef HAVE_C99_MATH -int pj_isnan (double x); -#endif - -/* Returns 0 if not a NaN and non-zero if val is a NaN */ -int pj_isnan (double x) { - /* cppcheck-suppress duplicateExpression */ - return x != x; -} -- cgit v1.2.3