Keywords: map

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### Typical deconvolution session

           1 read beam demo
           2 read dirty demo
           3 input clean
           4 hogbom /flux 0 1
           5 show residual
           6 show clean
           7 write clean demo
           8 let name demo
           9 go noise
          10 let ares 0.5*noise
          11 input clean
          12 hogbom /flux 0 1
          13 let niter 2000
          14 input clean
          15 hogbom /flux 0 1
          16 show residual
          17 show clean
          18 for iplane 1 to 10
          19    show clean iplane
          20    support
          21    hogbom iplane /flux 0 1
          22    write support "demo-"'iplane'
          23 next iplane
          24 show residual
          25 show clean
          26 write residual demo
          27 write clean demo
          28 write cct demo
          29 let name demo
          30 let type lmv-clean
          31 go cct
          32 go view

Comments:

Steps 1-2
  Read dirty beam and dirty image from the `demo.beam` and `demo.lmv` files. Those steps are not needed if the dirty beam and image are already stored in the internal buffer, i.e. if you have imaged the table just before in the same MAPPING session.
Steps 3-6
  Print the current state of the control parameters, deconvolve the dirty image using the `HOGBOM` algorithm (step 3) and look at the results (residual and clean images). The `/flux 0 1` option pop-up the visualization of the cumulative flux deconvolved as the clean components are found.
Steps 8-12
  Estimate the empirical noise through the `GO NOISE` command after this first deconvolution and set the `ares` stopping criterion accordingly. Check that the new value of `ares` has been correctly set (step 11) and restart deconvolution.
Steps 13-17
  Increase the number of clean components as the previous deconvolution stopped before that the residual image reached the `ares` value. Restart deconvolution and look at results.
Steps 18-25
  Tries to improve deconvolution by definition of a support per plane and deconvolve this plane accordingly. The support is store in a file for memory. The deconvolution results are then displayed.
Steps 26-28
  Write residual image, clean image and clean component list in `demo.lmv-res`, `demo.lmv-clean` and `demo.cct` files for memory.
Steps 29-32
  Visualize the cumulative flux as a function of the clean component number and visualize the clean spectra cube in an interactive way.

Typical deconvolution session using other `CLEAN` algorithm would look very similar. The main difference would be the possible tuning of other control parameters. A deconvolution session using `MX` would start differently as the imaging and deconvolution are done in the same step:

           1 read uv demo
           2 input uv_map
           3 input clean
           4 mx /flux 0 1
           5 show residual
           6 show clean
           7 write beam demo
           8 write dirty demo
           9 write clean demo
          10 write residual demo
          11 write cct demo

Comments:

Step 1
  Read the `demo.uvt` table in an internal buffer.
Steps 2 and 3
  Check current state of the variables that control the imaging and deconvolution.
Steps 4-6
  Deconvolve and look at the results.
Steps 7-11
  Write all the internal buffers for memory.

All the tuning of the typical imaging and deconvolution sessions could be fitted in this `MX` session although they are not repeated here.

Next: Comparison and practical advices Up: Implementation and typical use Previous: Implementation Contents Index