Last modified: December 2018

URL: http://cxc.harvard.edu/sherpa/ahelp/steplo1d.html
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AHELP for CIAO 4.11 Sherpa v1

steplo1d

Context: models

Synopsis

One-dimensional step function.

Syntax

steplo1d

Description

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


Example

>>> create_model_component("steplo1d", "mdl")
>>> print(mdl)

Create a component of the steplo1d model and display its default parameters. The output is:

mdl
   Param        Type          Value          Min          Max      Units
   -----        ----          -----          ---          ---      -----
   mdl.xcut     thawed            0 -3.40282e+38  3.40282e+38           
   mdl.ampl     thawed            1            0  3.40282e+38           

ATTRIBUTES

The attributes for this object are:

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

Bugs

See the bugs pages on the Sherpa website for an up-to-date listing of known bugs.

See Also

models
box1d, const1d, delta1d, stephi1d