StepLo1D¶

class sherpa.models.basic.StepLo1D(name='steplo1d')[source]

One-dimensional step function.

The model is flat below xcut, where it is set to the ampl parameter, and zero above this.

xcut

The position of the step.

ampl

The amplitude of the step.

Notes

The functional form of the model for points is:

f(x) = ampl if x <= xcut
= 0       otherwise


and for an integrated grid it is:

f(xlo,xhi) = ampl * (xhi - xlo)  if xhi <= xcut
= ampl * (xcut - xlo) if xlo <= xcut and xhi > xcut
= 0                   if xlo > xcut


Attributes Summary

Methods Summary

 apply(outer, *otherargs, **otherkwargs) calc(pars, xlo, *args, **kwargs) get_center() guess(dep, *args, **kwargs) Set an initial guess for the parameter values. regrid(*arrays) reset() set_center(*args, **kwargs) startup() Called before a model may be evaluated multiple times. teardown() Called after a model may be evaluated multiple times.

Attributes Documentation

thawedparhardmaxes
thawedparhardmins
thawedparmaxes
thawedparmins
thawedpars

Methods Documentation

apply(outer, *otherargs, **otherkwargs)
calc(pars, xlo, *args, **kwargs)
get_center()
guess(dep, *args, **kwargs)[source]

Set an initial guess for the parameter values.

Attempt to set the parameter values, and ranges, for the model to match the data values. This is intended as a rough guess, so it is expected that the model is only evaluated a small number of times, if at all.

regrid(*arrays)
reset()
set_center(*args, **kwargs)
startup()

Called before a model may be evaluated multiple times.

teardown()

Called after a model may be evaluated multiple times.

setup()