Usage for linfit
Return to directory of Todd's CASA extensions
Basic linear function fitter with error bars in the y-axis data points.
Uses scipy.optimize.leastsq(). Accepts either lists or arrays. See also
spectralindex. For linear fits with uncertainties
in both axes, see
orthogonalDistanceRegression.
Usage:
lf = au.linfit()
lf.linfit(x, y, yerror, pinit=[0.57, 3.4], plot=False, plotfile=None, xlabel=None,
ylabel=None, title=None, residual=False, excludeXrange=[], returnResiduals=False)
- Input:
- x, y: x and y axis values
- yerror: uncertainty in the y-axis values
- pinit contains the initial guess of [slope, intercept]
- residual: if True, show the residual of the fit in second panel
- excludeXrange: exclude a range of x-axis values when doing the fit e.g. [109,116] to avoid 109-116 GHz points
- returnResiduals: if True, return [slope,intercept,data-fit]
- Output:
- The fit result as: [slope, y-intercept], or [slope, y-intercept, data-fit]
Example:
CASA<5> lf = au.linfit()
CASA<6> x = [1,2,3,4,5]
CASA<7> y = [.43,.96,1.24,1.67,1.86]
CASA<8> yerror = [0.1,0.1,0.1,0.2,0.2]
CASA<9> lf.linfit(x, y, yerror, xlabel='my x label', ylabel='my y label', title='test', plotfile='test.png', plot=True)
Out[9]: array([ 0.31652522, 0.30612593])
--
ToddHunter - 2012-09-10
- test.png: