Accessing data with the Sherpa/S-Lang module functions.
Sherpa, the modeling and fitting application of the
Chandra Interactive Analysis of Observations (CIAO) software
package, was originally designed as a `black box': data were to
be input from a file, and analyzed, with results possibly written out to disk;
however, the data themselves were not
to be manipulated once input.
The embedding of the S-Lang scripting language into
Sherpa allows us to move from
this `black box' paradigm to one in which numeric data can be freely
moved into and out of the box, and
freely manipulated outside that box (e.g., with S-Lang functions).
This movement of data requires the new functionality of the
Sherpa/S-Lang module.
There are six principal types of Sherpa/S-Lang module functions,
differentiated by prefix:
Summary of Sherpa/S-Lang Module Function Types
| get |
Functions for retrieving data and settings from Sherpa
|
| is |
Query functions
|
| list |
Functions for retrieving string-based information from
Sherpa and presenting it in tabular form
|
| load |
Functions for loading datasets, file-based
models, etc., into Sherpa
|
| run |
An extension of get functions
designed to run a computationally intensive task
(e.g., PROJECTION) and after completion return
numerical information to the user. (Each run function
has a corresponding get function, which simply
retrieves the information from the most recent previous run.)
|
| set |
Functions for putting data into Sherpa, or changing settings
|
Miscellaneous functions which are not classified into one of the six
types above include:
Other Sherpa/S-Lang Module Functions
| compute_errors |
Estimate errors for data given the current Sherpa statistic setting
|
| compute_statistic |
Compute a statistic given a data and model array, and the current Sherpa statistic setting
|
| create_model | create_inst_model |
Create a new instantiation of a Sherpa model
|
| restore_unc |
Restore the default settings of the configuration variable sherpa.unc |
| restore_proj |
Restore the default settings of the configuration variable sherpa.proj |
| restore_cov |
Restore the default settings of the configuration variable sherpa.cov |
| restore_intunc |
Restore the default settings of the configuration variable sherpa.intunc |
| restore_intproj |
Restore the default settings of the configuration variable sherpa.intproj |
| restore_regunc |
Restore the default settings of the configuration variable sherpa.regunc |
| restore_regproj |
Restore the default settings of the configuration variable sherpa.regproj |
The Sherpa module can now be loaded by using the require("sherpa"); statement, although the previous method (loading with the import command) still works.
- chandra
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guide
- sherpa
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bye,
calc_kcorr,
dataspace,
dcounts,
dollarsign,
echo,
eflux,
eqwidth,
erase,
flux,
get,
get_dcounts_sum,
get_dir,
get_eflux,
get_eqwidth,
get_filename,
get_flux2d,
get_flux_str,
get_lfactorial,
get_mcounts_sum,
get_pflux,
get_source_components,
get_verbose,
groupbycounts,
guess,
is,
journal,
list,
list_par,
mcounts,
numbersign,
paramest,
plot_eprof,
plot_rprof,
prompt,
reset,
run,
set,
set_analysis,
set_axes,
set_coord,
set_dataspace,
set_dir,
set_verbose,
setplot,
sherpa_plotfns,
sherpa_utils,
show,
simspec,
use,
version
|
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