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sd.scantable.cspline_baseline - Function

5.1.2 Perform a baseline subtraction using cubic spline function
Description

Return a scan which has been baselined (all rows) by cubic spline function (piecewise cubic polynomial). Fit will be done with ’sigma-clipping’.

Note: The best-fit parameter values output in logger and/or blfile are now based on specunit of ’channel’.

Arguments





Inputs

insitu

If False a new scantable is returned

allowed: bool

Default: None (use default value)

mask

An optional mask retreived from scantable

allowed:

bool

Default:

None (no mask)

npiece

Number of pieces

allowed:

integer

Default:

2

clipthresh

Clipping threshold in unit of sigma

allowed:

float

Default:

3.0

clipniter

Maximum number of iteration of clipping

allowed:

integer

Default:

0

plot

Plot the fit and the residual (currently unavailable)

allowed:

bool

Default:

False

getresidual

If False, return best-fit value instead of residual

allowed:

bool

Default:

True

showprogress

Show progress status for large data

allowed:

bool

Default:

True

minnrow

Minimum number of spectra to show progress status

allowed:

integer

Default:

1000

outlog

Output the coefficients of the best-fit function to logger

allowed:

bool

Default:

False

blfile

Name of text file in which the best-fit parameter values to be written

allowed:

string

Default:





Returns
scantable

Example

        scan = sd.scantable(’OrionS_rawACSmod_cal’,average=False)  
        # return a scan baselined by a cubic spline consisting of 2 pieces (i.e., 1 internal knot),  
        # also with 3-sigma clipping, iteration up to 4 times  
        bscan = scan.cspline_baseline(npiece=2,clipthresh=3.0,clipniter=4)


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