r25260 - in /trunk/target_functions: relax_fit.c relax_fit.h -- August 26, 2014 - 09:00

Author: bugman
Date: Tue Aug 26 09:00:14 2014
New Revision: 25260

URL: http://svn.gna.org/viewcvs/relax?rev=25260&view=rev
Log:
Implemented the target_functions.relax_fit.dfunc() gradient function.

This is using the Python/C interface to provide a Python function for 
calculating and returned the
chi-squared gradient for the exponential curves.


Modified:
    trunk/target_functions/relax_fit.c
    trunk/target_functions/relax_fit.h

Modified: trunk/target_functions/relax_fit.c
URL: 
http://svn.gna.org/viewcvs/relax/trunk/target_functions/relax_fit.c?rev=25260&r1=25259&r2=25260&view=diff
==============================================================================
--- trunk/target_functions/relax_fit.c  (original)
+++ trunk/target_functions/relax_fit.c  Tue Aug 26 09:00:14 2014
@@ -123,19 +123,45 @@
 
     /* Declarations */
     PyObject *params_arg;
-
-    /* Temp Declarations */
-    double aaa[MAXPARAMS] = {1.0, 2.0};
+    PyObject *element;
     int i;
-    double *params;
 
     /* Parse the function arguments, the only argument should be the 
parameter array */
     if (!PyArg_ParseTuple(args, "O", &params_arg))
         return NULL;
 
+    /* Place the parameter array elements into the C array */
+    for (i = 0; i < num_params; i++) {
+        /* Get the element */
+        element = PySequence_GetItem(params_arg, i);
+
+        /* Convert to a C double, then free the memory. */
+        params[i] = PyFloat_AsDouble(element);
+        Py_CLEAR(element);
+
+        /* Scale the parameter */
+        params[i] = params[i] * scaling_matrix[i];
+    }
+
     /* Back calculated the peak intensities */
     exponential(params, relax_times, back_calc, num_times);
 
+    /* The partial derivates */
+    exponential_dR(params, relax_times, back_calc_grad, num_times);
+    exponential_dI(params, relax_times, back_calc_grad, num_times);
+
+    /* The chi-squared gradient */
+    dchi2(dchi2_vals, values, back_calc, back_calc_grad, sd, num_times, 
num_params);
+
+    /* Convert to a Python list */
+    PyObject *list = PyList_New(0);
+    Py_INCREF(list);
+    for (i = 0; i < num_params; i++) {
+        PyList_Append(list, PyFloat_FromDouble(dchi2_vals[i]));
+    }
+
+    /* Return the Jacobian */
+    return list;
     return NULL;
 }
 

Modified: trunk/target_functions/relax_fit.h
URL: 
http://svn.gna.org/viewcvs/relax/trunk/target_functions/relax_fit.h?rev=25260&r1=25259&r2=25260&view=diff
==============================================================================
--- trunk/target_functions/relax_fit.h  (original)
+++ trunk/target_functions/relax_fit.h  Tue Aug 26 09:00:14 2014
@@ -40,6 +40,7 @@
 /* Variables used for storage during the function calls of optimisation */
 static double back_calc[MAXTIMES];
 static double back_calc_grad[MAXPARAMS][MAXTIMES];
+static double dchi2_vals[MAXPARAMS];
 static double params[MAXPARAMS];
 static double values[MAXTIMES];
 static double sd[MAXTIMES];