add a test of the get_solid_angle function

1 files changed, 44 insertions, 0 deletions

diff --git a/test.c b/test.c
new file mode 100644
index 0000000..62529ea
--- /dev/null
+++ b/test.c
@@ -0,0 +1,44 @@
+#include "solid_angle.h"
+#include <math.h>
+#include <stdio.h>
+
+int isclose(double a, double b, double rel_tol, double abs_tol)
+{
+    /* Returns 1 if a and b are "close". This algorithm is taken from Python's
+     * math.isclose() function.
+     *
+     * See https://www.python.org/dev/peps/pep-0485/. */
+    return fabs(a-b) <= fmax(rel_tol*fmax(fabs(a),fabs(b)),abs_tol);
+}
+
+int test_solid_angle(char *err)
+{
+    /* Tests the get_solid_angle() function. */
+    double pmt[3] = {0,0,0};
+    double pos[3] = {0,0,1};
+    double n[3] = {0,0,1};
+    double r = 1.0;
+    double solid_angle;
+
+    solid_angle = get_solid_angle(pos,pmt,n,r);
+
+    if (!isclose(solid_angle, 2*M_PI*(1-1/sqrt(2)), 1e-9, 0)) {
+        sprintf(err, "solid angle = %.2f, but expected %.2f", solid_angle, 2*M_PI*(1-1/sqrt(2)));
+        return 1;
+    }
+
+    return 0;
+}
+
+int main(int argc, char **argv)
+{
+    char err[256];
+
+    if (!test_solid_angle(err)) {
+        printf("[\033[92mok\033[0m] test_solid_angle\n");
+        return 0;
+    } else {
+        printf("[\033[91mfail\033[0m] test_solid_angle: %s\n", err);
+        return 1;
+    }
+}