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authorJörg Frings-Fürst <debian@jff-webhosting.net>2014-09-01 13:56:46 +0200
committerJörg Frings-Fürst <debian@jff-webhosting.net>2014-09-01 13:56:46 +0200
commit22f703cab05b7cd368f4de9e03991b7664dc5022 (patch)
tree6f4d50beaa42328e24b1c6b56b6ec059e4ef21a5 /numlib/tdhsx.c
Initial import of argyll version 1.5.1-8debian/1.5.1-8
Diffstat (limited to 'numlib/tdhsx.c')
-rw-r--r--numlib/tdhsx.c117
1 files changed, 117 insertions, 0 deletions
diff --git a/numlib/tdhsx.c b/numlib/tdhsx.c
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+
+/*
+ * Code to test the downhill simplex minimiser
+ *
+ * Copyright 1999 - 2005 Graeme W. Gill
+ * All rights reserved.
+ *
+ * This material is licenced under the GNU AFFERO GENERAL PUBLIC LICENSE Version 3 :-
+ * see the License.txt file for licencing details.
+ */
+
+#include <stdio.h>
+#include "numlib.h"
+
+/* Final approximate solution: */
+
+double expect[9] = {
+ -0.5706545E+00,
+ -0.6816283E+00,
+ -0.7017325E+00,
+ -0.7042129E+00,
+ -0.7013690E+00,
+ -0.6918656E+00,
+ -0.6657920E+00,
+ -0.5960342E+00,
+ -0.4164121E+00 };
+
+double fcn( /* Return function value */
+ void *fdata, /* Opaque data pointer */
+ double tp[]); /* Multivriate input value */
+
+#define N 9
+
+int main(void)
+{
+ double cp[N]; /* Function input values */
+ double s[N]; /* Search area */
+ double err;
+ int j;
+ int nprint = 0; /* Itteration debugging print = off */
+ int rv;
+
+ error_program = "tdhsx"; /* Set global error reporting string */
+
+ /* The following starting values provide a rough solution. */
+ for (j = 0; j < N; j++) {
+ cp[j] = -1.f;
+ s[j] = 0.9;
+ }
+
+ nprint = 0;
+
+ /* Set tol to the square root of the machine precision. */
+ /* Unless high precision solutions are required, */
+ /* this is the recommended setting. */
+
+ rv = dhsx(
+ &err, /* return residual */
+ N, /* Dimentionality */
+ cp, /* Initial starting point */
+ s, /* Size of initial search area */
+ 0.0000001, /* Tollerance of error change to stop on */
+ 1e6, /* Absolute error to stop on */
+// 10.0, /* Tollerance of error change to stop on */
+// 0.0001, /* Absolute error to stop on */
+ 1000, /* Maximum iterations allowed */
+ fcn, /* Error function to evaluate */
+ NULL); /* Opaque data needed by function */
+
+
+ fprintf(stdout,"Return code %d, residual err = %f:\n",rv, err);
+ for (j = 0; j < N; j++) {
+ fprintf(stdout,"cp[%d] = %e, expect %e\n",j,cp[j],expect[j]);
+ }
+
+ return 0;
+} /* main() */
+
+/* Function being minimized */
+double fcn( /* Return function value */
+void *fdata, /* Opaque data pointer */
+double tp[] /* Multivriate input value */
+) {
+ double err, tt;
+ double temp, temp1, temp2;
+ int k;
+
+ /* Function Body */
+ err = 0.0;
+ for (k = 0; k < N; ++k) {
+ temp = (3.0 - 2.0 * tp[k]) * tp[k];
+ temp1 = 0.0;
+ if (k != 0) {
+ temp1 = tp[k-1];
+ }
+ temp2 = 0.0;
+ if (k != ((N)-1))
+ temp2 = tp[k+1];
+ tt = temp - temp1 - 2.0 * temp2 + 1.0;
+ err += tt * tt;
+ }
+ err = sqrt(err);
+// printf("Returning %16.14f\n",err);
+ return err;
+}
+
+
+
+
+
+
+
+
+
+
+
+