Add math functions to posix and metro-snek builds. Add tests.

These implement most of the standard Python3 math functions, except
for math.frexp, math.fsum and math.modf

These are optional and not included in the snek-duino build

Signed-off-by: Keith Packard <keithp@keithp.com>

metro-snek/Makefile

@@ -72,11 +72,13 @@ SNEK_LOCAL_SRC = \
 	ao_snek.c \
 	snek_altos.c \
 	snek_eeprom.c \
+	snek-math.c \
 	snek_gpio.c \
 	snek_io.c
 
 SNEK_LOCAL_BUILTINS = \
-	snek-altos.builtin
+	snek-altos.builtin \
+	../snek-math.builtin
 
 SNEK_ROOT = $(HOME)/src/snek
 

posix/Makefile

@@ -17,14 +17,15 @@ SNEK_ROOT=..
 SNEK_LOCAL_SRC = \
 	snek-main.c \
 	snek-posix.c \
+	snek-math.c \
 	snek-curses.c
 
 SNEK_LOCAL_INC = snek-posix.h
-SNEK_LOCAL_BUILTINS = snek-posix.builtin
+SNEK_LOCAL_BUILTINS = snek-posix.builtin ../snek-math.builtin
 
 include $(SNEK_ROOT)/snek-install.defs
 
-OPT?=-O0
+OPT?=-O99
 
 CFLAGS+=-DSNEK_MEM_INCLUDE_NAME $(OPT) -g -I. $(SNEK_CFLAGS) -Werror $(CPPFLAGS)
 

snek-builtin.py

@@ -79,7 +79,9 @@ def load_builtins(filename):
     f = open(filename)
     for line in f.readlines():
         line = line.rstrip()
-        if line[0] == '#':
+        if len(line) == 0:
+            pass
+        elif line[0] == '#':
             if len(line) > 1 and line[1] != ' ':
                 headers += [line]
         else:

snek-lex.c

@@ -536,6 +536,31 @@ snek_lex(void)
 		case SNEK_BUILTIN_True:
 			snek_token_val.number = 1.0f;
 			RETURN(NUMBER);
+#ifdef SNEK_BUILTIN_math_pi
+		case SNEK_BUILTIN_math_pi:
+			snek_token_val.number = M_PI;
+			RETURN(NUMBER);
+#endif
+#ifdef SNEK_BUILTIN_math_e
+		case SNEK_BUILTIN_math_e:
+			snek_token_val.number = M_E;
+			RETURN(NUMBER);
+#endif
+#ifdef SNEK_BUILTIN_math_tau
+		case SNEK_BUILTIN_math_tau:
+			snek_token_val.number = 2 * M_PI;
+			RETURN(NUMBER);
+#endif
+#ifdef SNEK_BUILTIN_math_inf
+		case SNEK_BUILTIN_math_inf:
+			snek_token_val.number = INFINITY;
+			RETURN(NUMBER);
+#endif
+#ifdef SNEK_BUILTIN_math_nan
+		case SNEK_BUILTIN_math_nan:
+			snek_token_val.number = NAN;
+			RETURN(NUMBER);
+#endif
 		}
 
 		snek_token_val.id = id;

snek-math.builtin

@@ -0,0 +1,89 @@
+#
+# Copyright © 2019 Keith Packard <keithp@keithp.com>
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+# General Public License for more details.
+#
+
+#
+# Number-theoretic and representation functions
+#
+math.ceil, 1
+math.copysign, 2
+math.fabs, 1
+math.factorial, 1
+math.floor, 1
+math.fmod, 2
+# math.frexp, 1
+# math.fsum, 1
+math.gcd, 2
+math.isclose, -1
+rel_tol,-2
+abs_tol,-2
+math.isfinite, 1
+math.isinf, 1
+math.isnan, 1
+math.ldexp, 2
+# math.modf, 1
+math.remainder, 2
+math.trunc, 1
+math.round, 1
+#
+# Power and logarithmic functions
+#
+math.exp, 1
+math.expm1, 1
+math.exp2, 1
+math.log, 1
+math.log1p, 1
+math.log2, 1
+math.log10, 1
+math.pow, 2
+math.cbrt, 1
+#
+# Trigonometric functions
+#
+math.acos, 1
+math.asin, 1
+math.atan, 1
+math.atan2, 2
+math.cos, 1
+math.hypot, 2
+math.sin, 1
+math.tan, 1
+#
+# Angular conversion
+#
+math.degrees, 1
+math.radians, 1
+#
+# Hyperbolic functions
+#
+math.acosh, 1
+math.asinh, 1
+math.atanh, 1
+math.cosh, 1
+math.sinh, 1
+math.tanh, 1
+#
+# Special functions
+#
+math.erf, 1
+math.erfc, 1
+math.gamma, 1
+math.lgamma, 1
+#
+# constants
+#
+math.pi, -2
+math.e, -2
+math.tau, -2
+math.inf, -2
+math.nan, -2

snek-math.c

@@ -0,0 +1,148 @@
+/*
+ * Copyright © 2019 Keith Packard <keithp@keithp.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ */
+
+#include "snek.h"
+#include <math.h>
+
+#define make_builtin(name) snek_builtin_ ## name
+
+#define m1(name,func) snek_poly_t make_builtin(name)(snek_poly_t a) { return snek_float_to_poly(func(snek_poly_to_float(a))); }
+#define m2(name,func) snek_poly_t make_builtin(name)(snek_poly_t a, snek_poly_t b) { return snek_float_to_poly(func(snek_poly_to_float(a), snek_poly_to_float(b))); }
+
+m1(math_ceil, ceilf)
+m2(math_copysign, copysignf)
+m1(math_fabs, fabsf)
+
+static float
+factorialf(float f)
+{
+	float	result = 1;
+	if (f > 35)
+		return (float) INFINITY;
+	for (float x = 2; x <= f; x++)
+		result *= x;
+	return result;
+}
+
+m1(math_factorial, factorialf)
+m1(math_floor, floorf)
+m2(math_fmod, fmodf)
+/* frexp */
+/* fsum */
+
+static float
+gcdf(float af, float bf)
+{
+	int	a = fabsf(af);
+	int	b = fabsf(bf);
+
+	if (a == 0 || b == 0)
+		return 0.0f;
+	while (a > 1 && b > 1) {
+		int r = a % b;
+		a = b;
+		b = r;
+	}
+	return (float) a;
+}
+
+m2(math_gcd, gcdf)
+
+snek_poly_t
+snek_builtin_math_isclose(uint8_t nposition, uint8_t nnamed, snek_poly_t *args)
+{
+	if (nposition != 2) {
+		snek_error("wrong number of args: wanted 2, got %d", nposition);
+		return SNEK_NULL;
+	}
+	float	af = snek_poly_to_float(*args++);
+	float	bf = snek_poly_to_float(*args++);
+	float	rel_tol = 1e-6f;
+	float	abs_tol = 0.0f;
+
+	while (nnamed--) {
+		snek_id_t id = (snek_id_t) ((*args++).f);
+		float	v = snek_poly_to_float(*args++);
+		switch (id) {
+		case SNEK_BUILTIN_rel_tol:
+			rel_tol = v;
+			break;
+		case SNEK_BUILTIN_abs_tol:
+			abs_tol = v;
+			break;
+		}
+	}
+	float dist = fabsf(af - bf);
+	float tol = fmaxf(rel_tol * fmaxf(fabsf(af), fabsf(bf)), abs_tol);
+	return snek_bool_to_poly(dist <= tol);
+}
+
+m1(math_isfinite, isfinite)
+m1(math_isinf, isinff)
+m1(math_isnan, isnanf)
+m2(math_ldexp, ldexpf)
+/* modf */
+m2(math_remainder, remainderf)
+m1(math_trunc, truncf)
+m1(math_round, roundf)
+
+m1(math_exp, expf)
+m1(math_expm1, expm1f)
+m1(math_exp2, exp2f)
+m1(math_log, logf)
+m1(math_log1p, log1pf)
+m1(math_log2, log2f)
+m1(math_log10, log10f)
+m2(math_pow, powf)
+
+m1(math_acos, acosf)
+m1(math_asin, asinf)
+m1(math_atan, atanf)
+m2(math_atan2, atan2f)
+m1(math_cos, cosf)
+m2(math_hypot, hypotf)
+m1(math_sin, sinf)
+m1(math_tan, tanf)
+
+static float
+degreesf(float x) { return x * 180.0f / M_PI; }
+
+static float
+radiansf(float x) { return x * M_PI / 180.0f; }
+
+m1(math_degrees, degreesf)
+m1(math_radians, radiansf)
+
+m1(math_acosh, acoshf);
+m1(math_asinh, asinhf);
+m1(math_atanh, atanhf);
+m1(math_cosh, coshf);
+m1(math_sinh, sinhf);
+m1(math_tanh, tanhf);
+
+m1(math_erf, erff);
+m1(math_erfc, erfcf);
+m1(math_gamma, tgammaf);
+
+static float
+_lgammaf(float f)
+{
+	int sgn;
+	return lgammaf_r(f, &sgn);
+}
+
+m1(math_lgamma, _lgammaf);
+
+m1(math_cbrt, cbrtf)
+

test/Makefile

@@ -27,6 +27,7 @@ TESTS = \
 	for-nested.py \
 	global.py \
 	if.py \
+	math.py \
 	op.py \
 	range.py \
 	slice.py \