Index: /branches/eam_branch_20070921/psModules/src/objects/pmPSFtoMetadata.c
===================================================================
--- /branches/eam_branch_20070921/psModules/src/objects/pmPSFtoMetadata.c	(revision 14987)
+++ /branches/eam_branch_20070921/psModules/src/objects/pmPSFtoMetadata.c	(revision 14987)
@@ -0,0 +1,91 @@
+
+// create a psMetadata representation (human-readable) of a psf model
+psMetadata *pmPSFtoMetadata (psMetadata *metadata, pmPSF *psf)
+{
+
+    if (metadata == NULL) {
+        metadata = psMetadataAlloc ();
+    }
+
+    char *modelName = pmModelClassGetName (psf->type);
+    psMetadataAdd (metadata, PS_LIST_TAIL, "PSF_MODEL_NAME", PS_DATA_STRING, "PSF model name", modelName);
+
+    int nPar = pmModelClassParameterCount (psf->type)    ;
+    psMetadataAdd (metadata, PS_LIST_TAIL, "PSF_MODEL_NPAR", PS_DATA_S32, "PSF model parameter count", nPar);
+
+    for (int i = 0; i < nPar; i++) {
+        psPolynomial2D *poly = psf->params->data[i];
+        if (poly == NULL)
+            continue;
+        psPolynomial2DtoMetadata (metadata, poly, "PSF_PAR%02d", i);
+    }
+
+    // XXX fix this
+    psWarning ("APTREND is currently missing");
+    // psPolynomial4DtoMetadata (metadata, psf->ApTrend, "APTREND");
+
+    psMetadataAdd (metadata, PS_LIST_TAIL, "PSF_AP_RESID", PS_DATA_F32, "aperture residual", psf->ApResid);
+    psMetadataAdd (metadata, PS_LIST_TAIL, "PSF_dAP_RESID", PS_DATA_F32, "aperture residual scatter", psf->dApResid);
+    psMetadataAdd (metadata, PS_LIST_TAIL, "PSF_SKY_BIAS", PS_DATA_F32, "sky bias level", psf->skyBias);
+
+    psMetadataAdd (metadata, PS_LIST_TAIL, "PSF_CHISQ", PS_DATA_F32, "chi-square for fit", psf->chisq);
+    psMetadataAdd (metadata, PS_LIST_TAIL, "PSF_NSTARS", PS_DATA_S32, "number of stars used to measure PSF", psf->nPSFstars);
+    psMetadataAdd (metadata, PS_LIST_TAIL, "PSF_POISSON_ERRORS", PS_DATA_BOOL, "Poisson errors for fits", psf->poissonErrors);
+
+    return metadata;
+}
+
+// parse a psMetadata representation (human-readable) of a psf model
+pmPSF *pmPSFfromMetadata (psMetadata *metadata)
+{
+
+    bool status;
+    char keyword[80];
+
+    char *modelName = psMetadataLookupPtr (&status, metadata, "PSF_MODEL_NAME");
+    pmModelType type = pmModelClassGetType (modelName);
+
+    bool poissonErrors = psMetadataLookupPtr (&status, metadata, "PSF_POISSON_ERRORS");
+    if (!status)
+        poissonErrors = true;
+
+    // we determine the PSF parameter polynomials from the MD-defined polynomials
+    pmPSF *psf = pmPSFAlloc (type, poissonErrors, NULL);
+
+    int nPar = psMetadataLookupS32 (&status, metadata, "PSF_MODEL_NPAR");
+    if (nPar != pmModelClassParameterCount (psf->type))
+        psAbort("mismatch model par count");
+
+    // un-fitted terms, not in the Metadata, are left NULL
+    // XXX add a double-check of the expected number?
+    for (int i = 0; i < nPar; i++) {
+        sprintf (keyword, "PSF_PAR%02d", i);
+        psMetadata *folder = psMetadataLookupPtr (&status, metadata, keyword);
+        if (!status)
+            continue;
+        psPolynomial2D *poly = psPolynomial2DfromMetadata (folder);
+        psFree (psf->params->data[i]);
+        psf->params->data[i] = poly;
+    }
+
+    // load the APTREND data
+    // XXX fix this to work with pmTrend2D
+    psWarning ("APTREND is not being read");
+    # if (0)
+    sprintf (keyword, "APTREND");
+    psMetadata *folder = psMetadataLookupPtr (&status, metadata, keyword);
+    psPolynomial4D *poly = psPolynomial4DfromMetadata (folder);
+    psFree (psf->ApTrend);
+    psf->ApTrend = poly;
+    # endif
+
+    psf->ApResid = psMetadataLookupF32 (&status, metadata, "PSF_AP_RESID");
+    psf->dApResid = psMetadataLookupF32 (&status, metadata, "PSF_dAP_RESID");
+    psf->skyBias = psMetadataLookupF32 (&status, metadata, "PSF_SKY_BIAS");
+
+    psf->chisq = psMetadataLookupF32 (&status, metadata, "PSF_CHISQ");
+    psf->nPSFstars = psMetadataLookupS32 (&status, metadata, "PSF_NSTARS");
+
+    psFree (metadata);
+    return (psf);
+}