diff --git a/math/fitting/__init__.py b/math/fitting/__init__.py index 268bd0a..dcd2509 100644 --- a/math/fitting/__init__.py +++ b/math/fitting/__init__.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 , 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 + + diff --git a/math/fitting/funcs_poly.py b/math/fitting/funcs_poly.py new file mode 100644 index 0000000..60e9fa2 --- /dev/null +++ b/math/fitting/funcs_poly.py @@ -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 , 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)) ]) + +