Last modified: December 2018

URL: http://cxc.harvard.edu/sherpa/ahelp/lorentz1d.html
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AHELP for CIAO 4.11 Sherpa v1

lorentz1d

Context: models

Synopsis

One-dimensional normalized Lorentz model function.

Syntax

lorentz1d

Example

>>> create_model_component("lorentz1d", "mdl")
>>> print(mdl)

Create a component of the lorentz1d model and display its default parameters. The output is:

mdl
   Param        Type          Value          Min          Max      Units
   -----        ----          -----          ---          ---      -----
   mdl.fwhm     thawed           10            0  3.40282e+38           
   mdl.pos      thawed            1 -3.40282e+38  3.40282e+38           
   mdl.ampl     thawed            1 -3.40282e+38  3.40282e+38           

ATTRIBUTES

The attributes for this object are:

fwhm

The full-width half maximum of the line.

pos

The center of the line.

ampl

The amplitude refers to the integral of the model.

Notes

The functional form of the model for points is:

f(x) =                A * fwhm
       --------------------------------------
       2 * pi * (0.25 * fwhm^2 + (x - pos)^2)

   A = ampl / integral f(x) dx

and for an integrated grid it is the integral of this over the bin.


Bugs

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

See Also

models
beta1d, normbeta1d