1.1.1.0 image.fitprofile

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image.fitprofile - Function

1.1.1 Fit 1-dimensional profile with functional forms
Description

This function fits 1-dimensional models to profiles. All data in the specified region (except along the fitting axis) are averaged.

The behaviour is primarily controlled by argument fit.

If fit==T then you need an estimate. If estimate is unset, then that estimate is automatically provided by fitting ngauss gaussians. If estimate is set then it is used to provide the initial estimate.

The functional form that is actually fit for will be any polynomial specified by the poly argument, plus the number of gaussians present in the estimate.

If fit==F then an estimate is created and returned. If estimate is empty, than an estimate for ngauss gaussians is made. If estimate is not empty, then it is just evaluated.

After calling this function, argument values holds the fitted or estimated profile values, and argument resid holds the fitted or estimated residual profile values. Look at the example for information on accessing returned values.

The output mask is a copy of the default input pixel mask (if any); the OTF mask does not contribute. Any other input pixel masks will not be copied. Use function maskhandler if you need to copy other masks too. Use function calcmask if you need to apply the OTF mask to the output.

Arguments


Outputs
values	Output fitted or estimated profile
	allowed:	doubleArray
	Default:
resid	Output residual profile
	allowed:	doubleArray
	Default:
Inputs
region	The region of interest. Default is whole image.
	allowed:	any
	Default:	record
axis	The profile axis. Default is spectral axis.
	allowed:	int
	Default:	-1
mask	OTF mask, Boolean LEL expression or mask region. Default is none.
	allowed:	any
	Default:	variant
estimate	Initial estimate. Default is unset.
	allowed:	any
	Default:	record
ngauss	Number of Gaussian elements. Default is one.
	allowed:	int
	Default:	-1
poly	Order of polynomial element. Default is unset.
	allowed:	int
	Default:	-1
fit	Do fit or get estimate
	allowed:	bool
	Default:	true
sigma	Weights image. Default is unset.
	allowed:	string
	Default:

Returns
anyrecord

Example

"""
#
print "\t----\t fitprofile Ex 1 \t----"
ia.maketestimage(’gc.small’, overwrite=true)
fit = ia.fitprofile(axis=1, fit=T) # Auto-est and fit
print fit.keys()
#print fit[’return’]
#print fit[’values’]
#print fit[’resid’]

ia.close()
#
"""

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