Supported visibility formats for writing

The following examples illustrate how to produce each of the supported visibility file formats with solutions-apply, but other aspects of hyperdrive are also able to produce these file formats, and all aspects are able to perform averaging and write to multiple outputs.

Measurement sets

hyperdrive solutions-apply \
    -d *gpubox*.fits *.metafits \
    -s hyp_sols.fits \
    -o hyp_cal.ms

uvfits

hyperdrive solutions-apply \
    -d *gpubox*.fits *.metafits \
    -s hyp_sols.fits \
    -o hyp_cal.uvfits

A copy of the uvfits standard is here.

Visibility averaging

When writing out visibilities, they can be averaged in time and frequency. Units can be given to these; e.g. using seconds and kiloHertz:

hyperdrive solutions-apply \
    -d *gpubox*.fits *.metafits *.mwaf \
    -s hyp_sols.fits \
    -o hyp_cal.ms \
    --time-average 8s \
    --freq-average 80kHz

Units are not required; in this case, these factors multiply the observation's time and freq. resolutions:

hyperdrive solutions-apply \
    -d *gpubox*.fits *.metafits *.mwaf \
    -s hyp_sols.fits \
    -o hyp_cal.ms \
    --time-average 4 \
    --freq-average 2

If the same observation is used in both examples, with a time resolution of 2s and a freq. resolution of 40kHz, then both commands will yield the same result.

See this page for information on how visibilities are averaged in time and frequency.

Writing to multiple visibility outputs

All aspects of hyperdrive that can write visibilities can write to multiple outputs. Note that it probably does not make sense to write out more than one of each kind (e.g. two uvfits files), as each of these files will be exactly the same, and a simple cp from one to the other is probably faster than writing to two files simultaneously from hyperdrive.

Example (a measurement set and uvfits):

hyperdrive solutions-apply \
    -d *gpubox*.fits *.metafits *.mwaf \
    -s hyp_sols.fits \
    -o hyp_cal.ms hyp_cal.uvfits \
    --time-average 4 \
    --freq-average 2