#!/usr/bin/env python
##############################################################################
#
# PDFgui by DANSE Diffraction group
# Simon J. L. Billinge
# (c) 2006 trustees of the Michigan State University.
# All rights reserved.
#
# File coded by: Pavol Juhas
#
# See AUTHORS.txt for a list of people who contributed.
# See LICENSE.txt for license information.
#
##############################################################################
"""Class Parameter for handling one refined parameter To be stored in
Fitting.parameters { idx : parameter } dictionary."""
from diffpy.pdfgui.control.controlerrors import (
ControlError,
ControlKeyError,
ControlRuntimeError,
ControlTypeError,
)
[docs]
class Parameter:
"""Parameter is class for value and properties of refined parameter.
Because the initial value of Parameter may come from another Fitting, it is
accessed by setInitial(), initialStr() and initialValue() methods.
Data members:
idx -- integer identifier of this parameter in PdfFit
name -- optional description
refined -- refined value of the parameter, float or None.
fixed -- flag for fixing the parameter in refinement [False]
Private members:
__initial -- stores the initial value, float, or "=fitname:idx" string
__fitrepr -- None or string representation of Fitting instance
"""
# fits should reference PDFGuiControl.fits
def __init__(self, idx, initial=0.0):
"""Initialize new parameter.
idx -- idx of this parameter in PdfFit
initial -- optional initial value of the parameter.
It can be float, Fitting, "=fitname" or "=fitname:idx" string.
"""
self.idx = idx
self.name = ""
self.refined = None
self.fixed = False
self.__initial = None
self.__fitrepr = None
self.setInitial(initial)
return
[docs]
def setInitial(self, initial):
"""Set initial value to float or refined value from another Fitting.
initial -- initial value, it can be something convertible to float,
Fitting reference or string in "=fitname" or
"=fitname:idx" format.
"""
self.__fitrepr = None
from diffpy.pdfgui.control.fitting import Fitting
try:
self.__initial = float(initial)
return
except (ValueError, TypeError):
pass
if isinstance(initial, Fitting):
self.__initial = "=" + initial.name
self.__fitrepr = repr(initial)
elif isinstance(initial, str) and initial[:1] == "=":
self.__initial = initial
self.__findLinkedFitting()
else:
raise ControlTypeError("invalid type of Parameter initial value")
return
[docs]
def initialStr(self):
"""Convert initial value to string.
returns string in "=fitname:idx" or "%f" format
"""
if isinstance(self.__initial, float):
s = str(self.__initial)
else:
self.__findLinkedFitting()
s = self.__initial
return s
[docs]
def initialValue(self):
"""Convert initial value to float.
For linked parameters it may raise:
ControlKeyError if source Fitting does not exist
KeyError when parameter does not exist
ControlRunTimeError for self-dependent parameters
returns the initial value
"""
if isinstance(self.__initial, float):
value = self.__initial
else:
try:
value = self.__getLinkedValue()
except RuntimeError as v:
# we will catch only recursion RuntimeError
if "maximum recursion" in str(v):
raise ControlRuntimeError("self-dependent parameter")
# other RuntimeError should be left alone
else:
raise
return float(value)
def __getLinkedValue(self):
"""Private retrieval of parameter value from linked Fitting."""
# Check to see if the fit name has a ':' in it
isplit = self.__initial.split(":")
# Who needs regular expressions?
try:
if len(isplit) == 1:
srcidx = self.idx
fitname = self.__initial[1:]
else:
srcidx = int(isplit[-1])
fitname = (":".join(isplit[:-1]))[1:]
except ValueError:
# __initial should be in the form "=fitname[:srcidx]"
raise ControlError("Malformed linked parameter %s" % self.__initial)
srcfit = self.__findLinkedFitting()
if srcfit is None:
raise ControlKeyError("Fitting '%s' does not exist" % fitname)
# Check to see if srcfit has parameter srcidx
try:
srcpar = srcfit.parameters[srcidx]
except KeyError:
raise ControlKeyError("Fitting '%s' has no parameter %s" % (fitname, srcidx))
if srcpar.refined is not None:
value = srcpar.refined
elif isinstance(srcpar.__initial, float):
value = srcpar.__initial
else:
value = srcpar.__getLinkedValue()
return value
def __findLinkedFitting(self):
"""Private search for linked Fitting by name and by representation.
Should be called only when initial value is linked to another Fitting.
Updates self.__initial and self.__fitrepr.
returns reference to Fitting when found or None
"""
# Check to see if the fit name has a ':' in it
isplit = self.__initial.split(":")
try:
srcidx = int(isplit[-1])
fitname = (":".join(isplit[:-1]))[1:]
except ValueError:
fitname = self.__initial[1:]
srcidx = self.idx
self.__initial += ":%i" % srcidx
from diffpy.pdfgui.control.pdfguicontrol import pdfguicontrol
fits = pdfguicontrol().fits
fitnames = [f.name for f in fits]
fitrepres = [repr(f) for f in fits]
# first find linked fitting by name
if fitname in fitnames:
idx = fitnames.index(fitname)
self.__fitrepr = fitrepres[idx]
ref = fits[idx]
# if not found by name, look up by representation
elif self.__fitrepr in fitrepres:
idx = fitrepres.index(self.__fitrepr)
self.__initial = "=%s:%i" % (fitnames[idx], srcidx)
ref = fits[idx]
# here self.__initial was not found, but let it pass
# maybe the linked fitting will be defined later
else:
self.__fitrepr = None
ref = None
return ref
# End of class Parameter