* Moved Poly_base & friends to wpylib.math.fitting.funcs_poly.

master
Wirawan Purwanto 9 years ago
parent 773177d2b0
commit 4111dc2da7
  1. 102
      math/fitting/__init__.py
  2. 119
      math/fitting/funcs_poly.py

@ -24,106 +24,6 @@ except ImportError:
last_fit_rslt = None
last_chi_sqr = None
class Poly_base(object):
"""Typical base class for a function to fit a polynomial. (?)
The following members must be defined to use the basic features in
this class---unless the methods are redefined appropriately:
* order = the order (maximum exponent) of the polynomial.
* dim = dimensionality of the function domain (i.e. the "x" coordinate).
A 2-dimensional (y vs x) fitting will have dim==1.
A 3-dimensional (z vs (x,y)) fitting will have dim==2.
And so on.
"""
# Must set the following:
# * order = ?
# * dim = ?
#def __call__(C, x):
# raise NotImplementedError, "must implement __call__"
def __init__(self, xdata=None, ydata=None, ndim=None):
if xdata != None:
self.dim = len(xdata)
elif ndim != None:
self.dim = ndim
else:
raise ValueError, "Either xdata or ndim argument must be supplied"
if ydata: self.guess = [ numpy.mean(ydata) ] + [0.0] * (self.order*self.dim)
def Guess(self, ydata):
"""The simplest guess: set the parameter for the constant term to <y>, and
the rest to zero. In general, this may not be the best."""
return [ numpy.mean(ydata) ] + [0.0] * (self.NParams() - 1)
def NParams(self):
'''Default NParams for polynomial without cross term.'''
return 1 + self.order*self.dim
class Poly_order2(Poly_base):
"""Multidimensional polynomial of order 2 without cross terms."""
order = 2
def __call__(self, C, x):
return C[0] \
+ sum([ C[i*2+1] * x[i] + C[i*2+2] * x[i]**2 \
for i in xrange(len(x)) ])
class Poly_order2_only(Poly_base):
"""Multidimensional polynomial of order 2 without cross terms.
The linear terms are deleted."""
order = 1 # HACK: the linear term is deleted
def __call__(self, C, x):
return C[0] \
+ sum([ C[i+1] * x[i]**2 \
for i in xrange(len(x)) ])
class Poly_order2x_only(Poly_base):
'''Multidimensional order-2-only polynomial with all the cross terms.'''
order = 2 # but not used
def __call__(self, C, x):
ndim = self.dim
# Reorganize the coeffs in the form of symmetric square matrix
# For 4x4 it will become like:
# [ 1, 5, 6, 7]
# [ 5, 2, 8, 9]
# [ 6, 8, 3, 10]
# [ 7, 9, 10, 4]
Cmat = numpy.diag(C[1:ndim+1])
j = ndim+1
for r in xrange(0, ndim-1):
jnew = j + ndim - 1 - r
Cmat[r, r+1:] = C[j:jnew]
Cmat[r+1:, r] = C[j:jnew]
j = jnew
#print Cmat
#print x
nrec = len(x[0]) # assume a 2-D array
rslt = numpy.empty((nrec,), dtype=numpy.float64)
for r in xrange(nrec):
rslt[r] = C[0] \
+ numpy.sum( Cmat * numpy.outer(x[:,r], x[:,r]) )
return rslt
def NParams(self):
# 1 is for the constant term
return 1 + self.dim * (self.dim + 1) / 2
class Poly_order3(Poly_base):
"""Multidimensional polynomial of order 3 without cross terms.
The linear terms are deleted."""
order = 3
def __call__(self, C, x):
return C[0] \
+ sum([ C[i*3+1] * x[i] + C[i*3+2] * x[i]**2 + C[i*3+3] * x[i]**3 \
for i in xrange(len(x)) ])
class Poly_order4(Poly_base):
"""Multidimensional polynomial of order 4 without cross terms.
The linear terms are deleted."""
order = 4
def __call__(self, C, x):
return C[0] \
+ sum([ C[i*4+1] * x[i] + C[i*4+2] * x[i]**2 + C[i*4+3] * x[i]**3 + C[i*4+4] * x[i]**4 \
for i in xrange(len(x)) ])
class fit_result(result_base):
"""The basic values expected in fit_result are:
- xopt
@ -477,3 +377,5 @@ def fit_func(Funct, Data=None, Guess=None, Params=None,
except:
x = "(?)"
raise ValueError, "Invalid `outfmt' argument = " + x

@ -0,0 +1,119 @@
#
# wpylib.math.fitting.funcs_poly module
# Created: 20150520
# Wirawan Purwanto
#
# Split 20150520 from wpylib.math.fitting module
#
"""
Module wpylib.math.fitting.funcs_poly
Legacy examples for 2-D polynomial function ansatz for fitting.
Newer applications should
"""
class Poly_base(object):
"""Typical base class for a function to fit a polynomial. (?)
The following members must be defined to use the basic features in
this class---unless the methods are redefined appropriately:
* order = the order (maximum exponent) of the polynomial.
* dim = dimensionality of the function domain (i.e. the "x" coordinate).
A 2-dimensional (y vs x) fitting will have dim==1.
A 3-dimensional (z vs (x,y)) fitting will have dim==2.
And so on.
"""
# Must set the following:
# * order = ?
# * dim = ?
#def __call__(C, x):
# raise NotImplementedError, "must implement __call__"
def __init__(self, xdata=None, ydata=None, ndim=None):
if xdata != None:
self.dim = len(xdata)
elif ndim != None:
self.dim = ndim
else:
raise ValueError, "Either xdata or ndim argument must be supplied"
if ydata: self.guess = [ numpy.mean(ydata) ] + [0.0] * (self.order*self.dim)
def Guess(self, ydata):
"""The simplest guess: set the parameter for the constant term to <y>, and
the rest to zero. In general, this may not be the best."""
return [ numpy.mean(ydata) ] + [0.0] * (self.NParams() - 1)
def NParams(self):
'''Default NParams for polynomial without cross term.'''
return 1 + self.order*self.dim
class Poly_order2(Poly_base):
"""Multidimensional polynomial of order 2 without cross terms."""
order = 2
def __call__(self, C, x):
return C[0] \
+ sum([ C[i*2+1] * x[i] + C[i*2+2] * x[i]**2 \
for i in xrange(len(x)) ])
class Poly_order2_only(Poly_base):
"""Multidimensional polynomial of order 2 without cross terms.
The linear terms are deleted."""
order = 1 # HACK: the linear term is deleted
def __call__(self, C, x):
return C[0] \
+ sum([ C[i+1] * x[i]**2 \
for i in xrange(len(x)) ])
class Poly_order2x_only(Poly_base):
'''Multidimensional order-2-only polynomial with all the cross terms.'''
order = 2 # but not used
def __call__(self, C, x):
ndim = self.dim
# Reorganize the coeffs in the form of symmetric square matrix
# For 4x4 it will become like:
# [ 1, 5, 6, 7]
# [ 5, 2, 8, 9]
# [ 6, 8, 3, 10]
# [ 7, 9, 10, 4]
Cmat = numpy.diag(C[1:ndim+1])
j = ndim+1
for r in xrange(0, ndim-1):
jnew = j + ndim - 1 - r
Cmat[r, r+1:] = C[j:jnew]
Cmat[r+1:, r] = C[j:jnew]
j = jnew
#print Cmat
#print x
nrec = len(x[0]) # assume a 2-D array
rslt = numpy.empty((nrec,), dtype=numpy.float64)
for r in xrange(nrec):
rslt[r] = C[0] \
+ numpy.sum( Cmat * numpy.outer(x[:,r], x[:,r]) )
return rslt
def NParams(self):
# 1 is for the constant term
return 1 + self.dim * (self.dim + 1) / 2
class Poly_order3(Poly_base):
"""Multidimensional polynomial of order 3 without cross terms.
The linear terms are deleted."""
order = 3
def __call__(self, C, x):
return C[0] \
+ sum([ C[i*3+1] * x[i] + C[i*3+2] * x[i]**2 + C[i*3+3] * x[i]**3 \
for i in xrange(len(x)) ])
class Poly_order4(Poly_base):
"""Multidimensional polynomial of order 4 without cross terms.
The linear terms are deleted."""
order = 4
def __call__(self, C, x):
return C[0] \
+ sum([ C[i*4+1] * x[i] + C[i*4+2] * x[i]**2 + C[i*4+3] * x[i]**3 + C[i*4+4] * x[i]**4 \
for i in xrange(len(x)) ])
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