################## GENERAL #################
Useful adverbs
- UCAT, MCAT, PCAT: list the UV, image, and UV+image data
- GETN: quickly get the file in the disk
- ZAP: delete an AIPS file
- A useful line to delete a series of data: for i= 1 to 9; get i; clrsta; zap
- RECAT: renumber the AIPS files
- ABORT: abort a task
- CLRSTA: clear status, do this after "ABORT"
- TVINIT: initialize the TV window
- TVLOD: load the image file into TV
- EXTDEST: delete an extension file, e.g. an attached table
- ALLDEST: massive delesions consistent with the inputs
- CLRMSG: to clear and compress your message file
- EXIT: exit aips

Useful tasks
- TVCPS: print the TV screen to a file or set to the printer

################## NORMAL PROCEDURE #############
Loading data and intial examination
- FITLD: load fits file into aips. e.g., the directory is '$AIPS/FITS/file.fits', then 
        default 'FITLD'
        datain = 'FITS:file.fits'
        outname = 'outname
- FILLM: read old VLA archive data
- BDFLIST: list the information of the BDFSDM data file 
- BDF2AIPS: import the BDFSDM data file into AIPS, for EVLA data
- PRTAN: list the antenna information
- LISTR: list the source, scan, IF, etc. information, using optype = 'SCAN'
- UVPLT: see the visibility data, with various options, e.g. UV coverage, uvdist vs amp/pha, etc.
- POSSM: good tool to plot freq vs amp/pha, and look at the bandpass, RFI, etc.

Data flaging
- LISTR: a useful tool to look at the data
- TVFLG: an interactive data flagging tool
- UVFLG: flag bad data by antenna, time, etc.
- CLIP: clip the unusually high or low visibility data points.
- QUACK: flag the non-useable a few data points at the beginning or end of each scan

Calibration
- SETJY: enter source infor into the source (SU) table; scale the model to the total flux.
- CALIB: providing the calibrator source(s), generate an antenna solution table (SN) table (for the calibration scans). Note flag table need to be applied. 
    - run both the flux calibrator and phase calibrator, and save to different SN tables. Note some calibrators have limits on UV range or antennas (e.g 3c48, from 0 to 40 in kilowavelengths) esp at high frequencies.
- SNPLT: plot the results of SN (gain solution) table
- GETJY: apply flux density (SU table) to the calibrators, based on the SU table and antenna solutions in the SN table and update the SN table with correct fluxes.
- SNPLT: look at the 'TY' table to look at the system temperature (TSYS)
- TACOP: we haven't do anything to the CL table yet. Keep the original one by coping it to a new one. Apply changes to the new one subsequently.
- SOLCL: this is for the old VLA.generate a new CL table with solar calibrations based on comparison between Tsys and Solcals. Note not all antennas are equipped with Solcals, must use those with Solcals as references.
- CLCAL: apply SN table to a newer CL table for all the data (calibrator and source)
- UVPLT: see the results by applying the CL table 
- SPLIT: split the UV data to different sources by applying the flagging and CL tables. After this, new UV images are generated, no CL table is needed
- UVSRT
- UVSUB

Imaging
- IMAGR: make an image, dirty or CLEANed.
- TVLOD: load the image
- TVSTAT: show the image status, e.g. the rms


############### EVLA SOLAR DATA PROCESSING ###############
1. The observing strategy:
- slew to the Sun, with the 20 dB attenuator in, set the T304 downconverter attenuation on the Sun, and
  remember the setting
- slew to the calibrator, take out the 20 dB attenuator, use the T304
  attenuation settings remembered.
- do the calibrator - Sun cycle for the rest of observation time.
- At each scan, after 5 seconds when the antennas are on source, set the requantizer gain.


2. Acquire and load data
- Go to the NRAO data archive, select the original SDMBDF file format, deselect "apply flags generated during observing", download
- BDFLIST: list the information of the SDMBDF database
- BDF2AIPS: import the BDFSDM file to AIPS. Remember when specifying the path to the SDMBDF file, the quote should be unclosed, e.g. ASDMF(1) = 'path_to_bdf_dir; ASDMF(2) = 'filename

3. Intial look at the data
- PRTAN
- LISTR
- UVPLT: because the output power is pretty weak when looking at the 
- POSSM: look at the calibrator, 

4. Apply the requantizer gain
- PRTAB: get a sense of the SY table, which column to edit: PDIF and PSUM for both polarizations.
- TACOP: copy the current SY table as a new one, to be edited
- TABED: edit the newer SY table, set all PDIF value to be 1, PSUM values to be anything except 1 (e.g. 10)
- TYAPL: apply the SY table to the data, and generate a newer UV data. Remember to set INVERS = 0 and IN2VERS = 2 (the edited SY table)
- LISTR: review the requantizer gain corrected data

5. Average and review the data 
- UVAVG: average the data to a longer sampling time, e.g. 1 s, and get a
  smaller database
- SPFLG: review the dynamic spectra of the data, find interesting time ranges.

6. Select and export the data into UVFITS format
- UVCOP: select a time range, copy the data from the uv data base created in
  step 3 as a new uv data base (with the full time resolution). Remember to
apply the online flags.
- FITTP: export the new uv data base to UVFITS format

7. Import the UVFITS data into CASA
- IMPORTUVFITS
- SPLIT: further split the data into smaller database by selecting the
  time ranges.

8. Review, calibrating and editing in CASA
- PLOTMS: review the data
- GAINCAL: delay and complex gain solution
- BANDPASS: bandpass calibration, use polynomial fit to get both the amplitude
  and phase bandpass. Be sure to check the 
- GENCAL: apply the multi-frequency-channel delay of the 20 dB attenuator to
  the data (mode mbd); antenna 20, left polarization has a ~50 degree phase offset, creat a new table to correct this.
- FLAGCMD, FLAGDATA, PLOTMS to edit the data
- SPLIT: apply the calibration tables, and split the "corrected" data column.
- EXPORTUVFITS: export the corrected data into UVFITS, to be analyzed in AIPS

9. Analyzing and Imaging in AIPS
- FITLD: load the UVFITS data into AIPS.
- UVDI1: vector subtraction, to get rid of the continuum emission
- SUBVS: written by T.S. Bastian. 
   - export TSB=/home/chen/tsbaips
   - start aips
   - version 'tsb'
   - task 'subvs'
   -
- IMAGR: clean the image. An automatic way would be: set a box using "TVBOX", set the clean paramters, do the clean IF by IF, using for i = 1:4; bif i; eif i; go; wait; end
- SUBIM: tear the image cubes apart (because every IF has an image cube), specify the IF number, using for i = 1:128; blc(3) i; trc(3) i; go; wait; end
- MCUBE: Combine all the image in channels together into a single cube (image
  x*image y*channels)
- TVMOV: Show the cleaned images in motion.
- TVPS: set the color, contrast
- TVLOD: load a specific frame of the image cube.
- TVZOM: zoom in the image.
- IMXY: read the X, Y coordinates from the cursor in pixels.
- MAXFIT: fit the maximum of a frame using a parabolic fit, give the program an coordinate of
  maximum (from IMXY) to start with.
- JMFIT: