cngf-pf

commit 505d04b123cfb85d445042d88900ed96df6d1d4e
parent bbd789ecc0cafb7a97bfd3f0fd07dc068e1745f6
Author: Anders Damsgaard <anders@adamsgaard.dk>
Date:   Thu, 22 Apr 2021 12:09:06 +0200

sync arrays.[ch] from granular

Diffstat:
M
arrays.c
 | 
35
++++++++++++++++++++++++++++-------
M
arrays.h
 | 
6
++++--

2 files changed, 32 insertions(+), 9 deletions(-)
diff --git a/arrays.c b/arrays.c
@@ -8,11 +8,9 @@
 void
 check_magnitude(const char *func_name, int limit, int value)
 {
-	if (value < limit) {
-		fprintf(stderr, "error: %s: input size %d is less than %d\n",
-		        func_name, value, limit);
-		exit(1);
-	}
+	if (value < limit)
+		errx(1, "%s: input size %d is less than %d\n",
+		     func_name, value, limit);
 }
 
 /* Translate a i,j,k index in grid with dimensions nx, ny, nz into a
@@ -290,8 +288,7 @@ normalize(const double *in, const int n)
 	double *out;
 
 	check_magnitude(__func__, 1, n);
-	if (!(out = calloc(n, sizeof(double))))
-		err(1, "%s: out calloc", __func__);
+	out = empty(n);
 	copy_values(in, out, n);
 	max_val = max(out, n);
 
@@ -327,3 +324,27 @@ euclidean_distance(const double *a, const double *b, const int n)
 
 	return sqrt(out);
 }
+
+double
+dot(const double *a, const double *b, const int n)
+{
+	int i;
+	double out = 0.0;
+
+	for (i = 0; i < n; i++)
+		out += a[i] * b[i];
+
+	return out;
+}
+
+double *
+cross(const double a[3], const double b[3])
+{
+	double *out = empty(3);
+
+	out[0] = a[1]*b[2] - a[2]*b[1];
+	out[1] = a[2]*b[0] - a[0]*b[2];
+	out[2] = a[0]*b[1] - a[1]*b[0];
+
+	return out;
+}
diff --git a/arrays.h b/arrays.h
@@ -1,8 +1,8 @@
-#include <stdio.h>
-
 #ifndef ARRAYS_
 #define ARRAYS_
 
+#include <stdio.h>
+
 unsigned int idx3(
         const unsigned int i, const unsigned int j, const unsigned int k,
         const unsigned int nx, const unsigned int ny);
@@ -53,5 +53,7 @@ double * normalize(const double *in, const int n);
 
 double euclidean_norm(const double *a, const int n);
 double euclidean_distance(const double *a, const double *b, const int n);
+double dot(const double *a, const double *b, const int n);
+double * cross(const double a[3], const double b[3]);
 
 #endif