use mwalib bscale

fixes MWATelescope/mwalib#85
MWATelescope · Nov 11, 2024 · 22b1251 · 22b1251
1 parent 95687f5
commit 22b1251
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Showing 2 changed files with 3 additions and 53 deletions.
diff --git a/src/io/mod.rs b/src/io/mod.rs
@@ -18,14 +18,10 @@ use log::{trace, warn};
 use crate::{
     marlu::{
         constants::MWA_LAT_RAD,
-        fitsio,
         hifitime::Duration,
         io::{ms::MeasurementSetWriter, uvfits::UvfitsWriter, VisWrite},
         mwalib,
-        mwalib::{
-            CorrelatorContext, MwalibError, _get_optional_fits_key, _open_hdu, fits_open_hdu,
-            get_optional_fits_key,
-        },
+        mwalib::{CorrelatorContext, MwalibError},
         rayon::prelude::*,
         Jones, LatLngHeight, MwaObsContext, ObsContext, RADec, SelectionError, VisContext,
         VisSelection, ENH,
@@ -56,59 +52,13 @@ pub struct IOContext {
 }
 
 impl IOContext {
-    // get the scale factor for the raw files
-    // will be deprecated after <https://github.com/MWATelescope/mwalib/issues/85> is resolved
-    fn get_raw_scale_factor(&self) -> f32 {
-        let mut meta_fptr = fitsio::FitsFile::open(&self.metafits_in).unwrap();
-        let hdu0 = fits_open_hdu!(&mut meta_fptr, 1).unwrap();
-        let mut scale_factor: Option<f32> =
-            get_optional_fits_key!(&mut meta_fptr, &hdu0, "RAWSCALE").unwrap();
-        let gpstime: Option<i32> =
-            get_optional_fits_key!(&mut meta_fptr, &hdu0, "GPSTIME").unwrap();
-        for raw_path in &self.gpufits_in {
-            let mut fptr = fitsio::FitsFile::open(raw_path).unwrap();
-            let hdu1 = fits_open_hdu!(&mut fptr, 1).unwrap();
-            for key in ["SCALEFAC", "BSCALE"] {
-                let this_scale_factor: Option<f32> =
-                    get_optional_fits_key!(&mut fptr, &hdu1, key).unwrap();
-                match (scale_factor, this_scale_factor) {
-                    (Some(sf), Some(this_sf)) => {
-                        assert!(
-                            ((sf - this_sf).abs() < f32::EPSILON),
-                            "Different scale factors found in raw files: {} and {}",
-                            sf,
-                            this_sf
-                        );
-                    }
-                    (None, Some(this_sf)) => {
-                        scale_factor = Some(this_sf);
-                    }
-                    _ => {}
-                }
-            }
-        }
-        match (scale_factor, gpstime) {
-            (Some(sf), _) => sf,
-            // according to pyuvdata "correlator did a divide by 4 before october 2014"
-            // https://github.com/RadioAstronomySoftwareGroup/pyuvdata/blob/05ee100af2e4e11c9d291c9eafc937578ef01763/src/pyuvdata/uvdata/mwa_corr_fits.py#L1464
-            (None, Some(t)) if t < 1096160568 => 0.25,
-            _ => {
-                warn!("No scale factor found in metafits or gpufits files, defaulting to 1.0");
-                1.0
-            }
-        }
-    }
-
     /// Get the `mwalib::CorrelatorContext` from metafits and gpufits
     ///
     /// # Errors
     ///
     /// see `mwalib::CorrelatorContext::new`
     pub fn get_corr_ctx(&self) -> Result<CorrelatorContext, MwalibError> {
-        CorrelatorContext::new(&self.metafits_in, &self.gpufits_in).map(|mut corr_ctx| {
-            corr_ctx.metafits_context.corr_raw_scale_factor = self.get_raw_scale_factor();
-            corr_ctx
-        })
+        CorrelatorContext::new(&self.metafits_in, &self.gpufits_in)
     }
 
     // TODO: pub fn validate_params(&self), checks permissions

diff --git a/src/van_vleck.rs b/src/van_vleck.rs
@@ -191,7 +191,7 @@ pub fn correct_van_vleck(
             nsamples: n2samples,
         });
     }
-    let sample_scale = n2samples as f64 * corr_ctx.metafits_context.corr_raw_scale_factor as f64;
+    let sample_scale = n2samples as f64 * corr_ctx.bscale as f64;
 
     // ant_pair indices which are unflagged autocorrelations, list of corresponding antenna indices
     let (unflagged_auto_mask, unflagged_autos): (Vec<_>, Vec<_>) = ant_pairs