Changeset 42078 for trunk/Ohana/src/opihi/cmd.astro/imfit-qgauss.c

Timestamp:

Feb 28, 2022, 12:10:28 PM (4 years ago)

Author:

eugene

Message:

add Molweide projection; improvements to source fitting functions (imfit) for testing

File:

• trunk/Ohana/src/opihi/cmd.astro/imfit-qgauss.c (modified) (4 diffs)

trunk/Ohana/src/opihi/cmd.astro/imfit-qgauss.c

@@ -25 +25 @@
   par[4]  = get_variable_default ("SXYg", 0);
   par[5]  = get_variable_default ("Zpk", 10000);
-  par[6]  = get_variable_default ("Sg", 0.0);
+  par[6]  = get_variable_default ("Sg", 0.0); // sky
   par[7]  = get_variable_default ("Sr", 1.0);
   fpar[0] = get_variable_default ("Npow", 2.25);
@@ -40 +40 @@
   set_variable ("Zpk",  par[5]);
   set_variable ("Sg",   par[6]);
-  set_variable ("Sr", par[7]);
+  set_variable ("Sr",   par[7]);
 }
 
-/* one component, two slopes: (1 + z^M + z^N)^(-1) -- x, y, sx, sy, sxy, I, sky, sr */
+/* qgauss: (1 + Sr*z + z^Npow)^(-1) -- x, y, sx, sy, sxy, I, sky, sr */
 opihi_flt qgaussTD (opihi_flt x, opihi_flt y, opihi_flt *par, int Npar, opihi_flt *dpar) {
   OHANA_UNUSED_PARAM(Npar);
@@ -60 +60 @@
   r = 1.0 / (1 + par[7]*z + pow(z,fpar[0]));
   f = par[5]*r + par[6];
-  q = par[5]*SQ(r)*(par[7] + fpar[0]*pow(z,(fpar[0]-1)));
 
   if (dpar != NULL) {
+    q = par[5]*SQ(r)*(par[7] + fpar[0]*pow(z,(fpar[0]-1)));
     dpar[0] = q*(2*px*par[2] + par[4]*Y);
     dpar[1] = q*(2*py*par[3] + par[4]*X);
@@ -75 +75 @@
 }
 
+/******************************************************************************
+ * this file defines the QGAUSS source shape model.  Note that these model functions are
+ * loaded by pmModelClass.c using 'include', and thus need no 'include' statements of
+ * their own.  The models use a psVector to represent the set of parameters, with the
+ * sequence used to specify the meaning of the parameter.  The meaning of the parameters
+ * may thus vary depending on the specifics of the model.  All models which are used as a
+ * PSF representations share a few parameters, for which # define names are listed in
+ * pmModel.h:
+
+   power-law with fitted linear term
+   1 / (1 + kz + z^2.25)
+
+   * PM_PAR_SKY 0   - local sky : note that this is unused and may be dropped in the future
+   * PM_PAR_I0 1    - central intensity
+   * PM_PAR_XPOS 2  - X center of object
+   * PM_PAR_YPOS 3  - Y center of object
+   * PM_PAR_SXX 4   - X^2 term of elliptical contour (SigmaX / sqrt(2))
+   * PM_PAR_SYY 5   - Y^2 term of elliptical contour (SigmaY / sqrt(2))
+   * PM_PAR_SXY 6   - X*Y term of elliptical contour
+   * PM_PAR_7   7   - amplitude of the linear component (k)
+   *****************************************************************************/