fit_one_of function to avoid redundant parameters (Trac #940) #149
Description
Could put some sort of function in model.py to identify which parameters should not all fit simultaneously, then flag to user as an issue.
e.g. for a simple particle:
fit_one_of('scale', 'sld', 'sld_solvent')
e.g. for a core-shell particle, think might need:
fit_one_of('scale', 'sld_core'.AND.'sld_shell'.AND.'sld_solvent')
There may be a better way to express this, or a clever way to to this automatically, certainly from the derivatives, or the correlation matrix. Also does not work always, e.g. if sld_shell is fixed at same as sld_solvent then the core/shell system beomes a simple particle, but could add extra logic for this???
Migrated from http://trac.sasview.org/ticket/940
{
"status": "assigned",
"changetime": "2017-04-10T08:12:30",
"_ts": "2017-04-10 08:12:30.091116+00:00",
"description": "\nCould put some sort of function in model.py to identify which parameters should not all fit simultaneously, then flag to user as an issue. \n\ne.g. for a simple particle:\n fit_one_of('scale', 'sld', 'sld_solvent')\n\ne.g. for a core-shell particle, think might need:\n fit_one_of('scale', 'sld_core'.AND.'sld_shell'.AND.'sld_solvent')\n\nThere may be a better way to express this, or a clever way to to this automatically, certainly from the derivatives, or the correlation matrix. Also does not work always, e.g. if sld_shell is fixed at same as sld_solvent then the core/shell system beomes a simple particle, but could add extra logic for this???\n",
"reporter": "richardh",
"cc": "",
"resolution": "",
"workpackage": "SasView Bug Fixing",
"time": "2017-04-09T08:07:16",
"component": "sasmodels",
"summary": "fit_one_of function to avoid redundant parameters",
"priority": "minor",
"keywords": "",
"milestone": "sasmodels WishList",
"owner": "pkienzle",
"type": "enhancement"
}