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Last modified: 26 October 2016

URL: http://cxc.harvard.edu/ciao/ahelp/index.html

Ahelp for CIAO

List of all Ahelp files: alphabetical or by context.

To learn how to use the help system for CIAO, type:

unix% ahelp

The help documents are accessed by subject (a single word, case insensitive). To get help on the tool dmextract:

To search on a word, use about (it is an alias to ahelp -k) which will bring up a list of all matching documents or - if there is only one match - display that document. Here we look for any document that mentions "merging":

unix% about merging
------------------------------------------------------------------------------------------------------------
|       SUBJECT        | CONTEXT |                                SYNOPSIS                                 |
|----------------------|---------|-------------------------------------------------------------------------|
| addresp              | tools   | Add multiple RMFs, weighted by ARFs and exposures; add mutiple ARFs,    |
|                      |         | weighted by exposures.                                                  |
|----------------------|---------|-------------------------------------------------------------------------|
| dmappend             | tools   | Append multiple blocks/extensions to an existing output file.           |
|----------------------|---------|-------------------------------------------------------------------------|
| dmpaste              | tools   | Add new columns to a table.                                             |
|----------------------|---------|-------------------------------------------------------------------------|
| dmregrid             | tools   | Rebin a stack of 2-dimensional images.                                  |
|----------------------|---------|-------------------------------------------------------------------------|
| dmregrid2            | tools   | shift, rotate, scale images                                             |
|----------------------|---------|-------------------------------------------------------------------------|
| merging_rules        | concept | A description of the merging rules used when combining header           |
|                      |         | information.                                                            |
|----------------------|---------|-------------------------------------------------------------------------|
| reproject_events     | tools   | Regrid an event file to a different tangent point                       |
|----------------------|---------|-------------------------------------------------------------------------|
| reproject_image      | tools   | Projects image from one WCS to another                                  |
|----------------------|---------|-------------------------------------------------------------------------|
| reproject_image_grid | tools   | Projects image from one WCS to another                                  |
------------------------------------------------------------------------------------------------------------

Use "ahelp subject" ("ahelp context subject" for non-unique cases) e.g.:
 ahelp reproject_image_grid
 ahelp tools reproject_image_grid

In general you will be now be able to say "ahelp <subject>" to read the help for that document. However, if the same subject matches different contexts, you have to say "ahelp <context> <subject>" as described at the end of the list of matches (e.g. "ahelp tools dmregrid").

Read the ahelp document for more information on the ahelp system, such as reading parts of the document - e.g. only the examples or the parameter list.


Last modified: 26 October 2016
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