Quickstart

Once installed, you can activate the virtual environment inside the project directory and run the CLI tool. The help message for the CLI can be accessed via the --help flag:

$ source <REPO-DIR>/.venv/bin/activate
$ ska-sdp-continuum-imaging-qa --help
usage: ska-sdp-continuum-imaging-qa [-h] [--output-dir OUTPUT_DIR] [--snr-threshold SNR_THRESHOLD] fits_image oskar_lsm

Compute QA metrics for an input FITS image.

positional arguments:
  fits_image            Path to the FITS image file.
  oskar_lsm             Path to the OSKAR-compatible ASCII LSM (stand-in for GSM).

options:
  -h, --help            show this help message and exit
  --output-dir OUTPUT_DIR
                        Directory to write output files to (default: a directory named after the input image stem).
  --snr-threshold SNR_THRESHOLD
                        Minimum SNR for sources included in QA metrics (default: 10.0).

Generating the QA metrics

The only mandatory arguments are the paths to the input files, a FITS image and a reference sky model, supplied to the CLI command via the two positional arguments:

ska-sdp-continuum-imaging-qa image.fits reference_lsm.txt

The command writes output files into the directory given by --output-dir or, if omitted, into a directory named after the FITS image stem under the current working directory. In the above case, the output files will be written to a directory named image/ under the current working directory.

Note

The following must be true of the two mandatory positional arguments:

• The first positional argument is a FITS image file output by WSClean.

• The second positional argument is an OSKAR-compatible fixed-format ASCII LSM file.

A successful run of the above command will produce the following output files in the output directory:

$ ls image/

image_flux_density_ratios.npy
image_positional_offsets.npy
image_qametrics.txt
image_matched_catalogue.csv
image_qa_summary.png