Function birli::flags::write_flags

source · [−]
pub fn write_flags(
    context: &CorrelatorContext, 
    flag_array: &Array3<bool>, 
    filename_template: &str, 
    mwalib_coarse_chan_range: &Range<usize>
) -> Result<(), IOError>
Expand description

Write flags to disk, given an observation’s [mwalib::CorrelatorContext], a vector of CxxFlagMasks for each baseline in the observation, a filename template and a vector of gpubox IDs.

The filename template should contain two or 3 percentage (%) characters which will be replaced by the gpubox id or channel number (depending on correlator type) provided in gpubox_ids. See [flag_io::FlagFileSet::new] for more details.

Examples

Here’s an example of how to flag some visibility files

use birli::{
    context_to_jones_array, write_flags, mwalib::CorrelatorContext,
    init_flag_array, get_antenna_flags, get_baseline_flags};
use tempfile::tempdir;

// define our input files
let metafits_path = "tests/data/1297526432_mwax/1297526432.metafits";
let gpufits_paths = vec![
    "tests/data/1297526432_mwax/1297526432_20210216160014_ch117_000.fits",
    "tests/data/1297526432_mwax/1297526432_20210216160014_ch117_001.fits",
    "tests/data/1297526432_mwax/1297526432_20210216160014_ch118_000.fits",
    "tests/data/1297526432_mwax/1297526432_20210216160014_ch118_001.fits",
];

// define a temporary directory for output files
let tmp_dir = tempdir().unwrap();

// define our output flag file template
let flag_template = tmp_dir.path().join("Flagfile%%%.mwaf");

// Create an mwalib::CorrelatorContext for accessing visibilities.
let context = CorrelatorContext::new(&metafits_path, &gpufits_paths).unwrap();

// Determine which timesteps and coarse channels we want to use
let img_coarse_chan_idxs = &context.common_coarse_chan_indices;
let img_timestep_idxs = &context.common_timestep_indices;

let img_timestep_range =
    *img_timestep_idxs.first().unwrap()..(*img_timestep_idxs.last().unwrap() + 1);
let img_coarse_chan_range =
    *img_coarse_chan_idxs.first().unwrap()..(*img_coarse_chan_idxs.last().unwrap() + 1);

// Prepare our flagmasks with known bad antennae
let flag_array = init_flag_array(
    &context,
    &img_timestep_range,
    &img_coarse_chan_range,
    None,
    None,
    None,
    Some(&get_baseline_flags(&context, &get_antenna_flags(&context))),
);

// read visibilities out of the gpubox files
let (jones_array, flag_array) = context_to_jones_array(
    &context,
    &img_timestep_range,
    &img_coarse_chan_range,
    Some(flag_array),
    false,
).unwrap();

// write the flags to disk as .mwaf
write_flags(&context, &flag_array, flag_template.to_str().unwrap(), &img_coarse_chan_range).unwrap();

Errors