# ASAP 'commands'

    ASAP> commands()
        [The scan container]
            scantable           - a container for integrations/scans
                                  (can open asap/rpfits/sdfits and ms files)
                copy            - returns a copy of a scan
                get_scan        - gets a specific scan out of a scantable
                                  (by name or number)
                drop_scan       - drops a specific scan out of a scantable
                                  (by number)
                set_selection   - set a new subselection of the data
                get_selection   - get the current selection object
                summary         - print info about the scantable contents
                stats           - get specified statistic of the spectra in
                                  the scantable
                stddev          - get the standard deviation of the spectra
                                  in the scantable
                get_tsys        - get the TSys
                get_time        - get the timestamps of the integrations
                get_sourcename  - get the source names of the scans
                get_azimuth     - get the azimuth of the scans
                get_elevation   - get the elevation of the scans
                get_parangle    - get the parallactic angle of the scans
                get_unit        - get the current unit
                set_unit        - set the abcissa unit to be used from this
                                  point on
                get_abcissa     - get the abcissa values and name for a given
                                  row (time)
                get_column_names - get the names of the columns in the scantable
                                   for use with selector.set_query
                set_freqframe   - set the frame info for the Spectral Axis
                                  (e.g. 'LSRK')
                set_doppler     - set the doppler to be used from this point on
                set_dirframe    - set the frame for the direction on the sky
                set_instrument  - set the instrument name
                set_feedtype    - set the feed type
                get_fluxunit    - get the brightness flux unit
                set_fluxunit    - set the brightness flux unit
                create_mask     - return an mask in the current unit
                                  for the given region. The specified regions
                                  are NOT masked
                get_restfreqs   - get the current list of rest frequencies
                set_restfreqs   - set a list of rest frequencies
                flag            - flag selected channels in the data
                lag_flag        - flag specified frequency in the data
                save            - save the scantable to disk as either 'ASAP',
                                  'SDFITS' or 'ASCII'
                nbeam,nif,nchan,npol - the number of beams/IFs/Pols/Chans
                nscan           - the number of scans in the scantable
                nrow            - te number of spectra in the scantable
                history         - print the history of the scantable
                get_fit         - get a fit which has been stored witnh the data
                average_time    - return the (weighted) time average of a scan
                                  or a list of scans
                average_pol     - average the polarisations together.
                average_beam    - average the beams together.
                convert_pol     - convert to a different polarisation type
                auto_quotient   - return the on/off quotient with
                                  automatic detection of the on/off scans (closest
                                  in time off is selected)
                mx_quotient     - Form a quotient using MX data (off beams)
                scale, *, /     - return a scan scaled by a given factor
                add, +, -       - return a scan with given value added
                bin             - return a scan with binned channels
                resample        - return a scan with resampled channels
                smooth          - return the spectrally smoothed scan
                poly_baseline   - fit a polynomial baseline to all Beams/IFs/Pols
                auto_poly_baseline - automatically fit a polynomial baseline
                recalc_azel     - recalculate azimuth and elevation based on
                                  the pointing
                gain_el         - apply gain-elevation correction
                opacity         - apply opacity correction
                convert_flux    - convert to and from Jy and Kelvin brightness
                                  units
                freq_align      - align spectra in frequency frame
                invert_phase    - Invert the phase of the cross-correlation
                swap_linears    - Swap XX and YY
                rotate_xyphase  - rotate XY phase of cross correlation
                rotate_linpolphase - rotate the phase of the complex
                                     polarization O=Q+iU correlation
                freq_switch     - perform frequency switching on the data
                stats           - Determine the specified statistic, e.g. 'min'
                                  'max', 'rms' etc.
                stddev          - Determine the standard deviation of the current
                                  beam/if/pol
         [Selection]
             selector              - a selection object to set a subset of a scantable
                set_scans          - set (a list of) scans by index
                set_cycles         - set (a list of) cycles by index
                set_beams          - set (a list of) beamss by index
                set_ifs            - set (a list of) ifs by index
                set_polarisations  - set (a list of) polarisations by name
                                     or by index
                set_names          - set a selection by name (wildcards allowed)
                set_tsys           - set a selection by tsys thresholds
                set_query          - set a selection by SQL-like query, e.g. BEAMNO==1
                reset              - unset all selections
                +                  - merge to selections

         [Math] Mainly functions which operate on more than one scantable

                average_time    - return the (weighted) time average
                                  of a list of scans
                quotient        - return the on/off quotient
                simple_math     - simple mathematical operations on two scantables,
                                  'add', 'sub', 'mul', 'div'
                quotient        - build quotient of the given on and off scans
                                  (matched pairs and 1 off/n on are valid)
                merge           - merge a list of scantables

         [Line Catalog]
            linecatalog              - a linecatalog wrapper, taking an ASCII or
                                       internal format table
                summary              - print a summary of the current selection
                set_name             - select a subset by name pattern, e.g. '*OH*'
                set_strength_limits  - select a subset by line strength limits
                set_frequency_limits - select a subset by frequency limits
                reset                - unset all selections
                save                 - save the current subset to a table (internal
                                       format)
                get_row              - get the name and frequency from a specific
                                       row in the table
         [Fitting]
            fitter
                auto_fit        - return a scan where the function is
                                  applied to all Beams/IFs/Pols.
                commit          - return a new scan where the fits have been
                                  commited.
                fit             - execute the actual fitting process
                store_fit       - store the fit parameters in the data (scantable)
                get_chi2        - get the Chi^2
                set_scan        - set the scantable to be fit
                set_function    - set the fitting function
                set_parameters  - set the parameters for the function(s), and
                                  set if they should be held fixed during fitting
                set_gauss_parameters - same as above but specialised for individual
                                       gaussian components
                get_parameters  - get the fitted parameters
                plot            - plot the resulting fit and/or components and
                                  residual
        [Plotter]
            asapplotter         - a plotter for asap, default plotter is
                                  called 'plotter'
                plot            - plot a scantable
                plot_lines      - plot a linecatalog overlay
                save            - save the plot to a file ('png' ,'ps' or 'eps')
                set_mode        - set the state of the plotter, i.e.
                                  what is to be plotted 'colour stacked'
                                  and what 'panelled'
                set_selection   - only plot a selected part of the data
                set_range       - set a 'zoom' window [xmin,xmax,ymin,ymax]
                set_legend      - specify user labels for the legend indeces
                set_title       - specify user labels for the panel indeces
                set_abcissa     - specify a user label for the abcissa
                set_ordinate    - specify a user label for the ordinate
                set_layout      - specify the multi-panel layout (rows,cols)
                set_colors      - specify a set of colours to use
                set_linestyles  - specify a set of linestyles to use if only
                                  using one color
                set_font        - set general font properties, e.g. 'family'
                set_histogram   - plot in historam style
                set_mask        - set a plotting mask for a specific polarization
                text            - draw text annotations either in data or relative
                                  coordinates
                arrow           - draw arrow annotations either in data or relative
                                  coordinates
                axhline,axvline - draw horizontal/vertical lines
                axhspan,axvspan - draw horizontal/vertical regions

            xyplotter           - matplotlib/pylab plotting functions

        [Reading files]
            reader              - access rpfits/sdfits files
                open            - attach reader to a file
                close           - detach reader from file
                read            - read in integrations
                summary         - list info about all integrations

        [General]
            commands            - this command
            print               - print details about a variable
            list_scans          - list all scantables created bt the user
            list_files          - list all files readable by asap (default rpf)
            del                 - delete the given variable from memory
            range               - create a list of values, e.g.
                                  range(3) = [0,1,2], range(2,5) = [2,3,4]
            help                - print help for one of the listed functions
            execfile            - execute an asap script, e.g. execfile('myscript')
            list_rcparameters   - print out a list of possible values to be
                                  put into $HOME/.asaprc
            rc                  - set rc parameters from within asap
            mask_and,mask_or,
            mask_not            - boolean operations on masks created with
                                  scantable.create_mask

        Note:
            How to use this with help:
                                             # function 'summary'
            [xxx] is just a category
            Every 'sub-level' in this list should be replaces by a '.' Period when
            using help
            Example:
                ASAP> help scantable # to get info on ths scantable
                ASAP> help scantable.summary # to get help on the scantable's
                ASAP> help average_time