Divergence (#79)

* Add exception

* Add divergence retry

Author: AlecThomson

arrakis/imager.py

@@ -24,7 +24,6 @@
 from astropy.visualization import (
     SqrtStretch,
     ImageNormalize,
-    MinMaxInterval,
 )
 from fitscube import combine_fits
 from fixms.fix_ms_corrs import fix_ms_corrs
@@ -52,6 +51,8 @@
     workdir_arg_parser,
 )
 
+from arrakis.utils.exceptions import DivergenceError
+
 matplotlib.use("Agg")
 
 TQDM_OUT = TqdmToLogger(logger, level=logging.INFO)
@@ -147,20 +148,15 @@ def get_mfs_image(
         if pol == "I"
         else f"{prefix_str}-MFS-{pol}-image.fits"
     )
-    mfs_model_name = (
-        f"{prefix_str}-MFS-model.fits"
-        if pol == "I"
-        else f"{prefix_str}-MFS-{pol}-model.fits"
-    )
     mfs_residual_name = (
         f"{prefix_str}-MFS-residual.fits"
         if pol == "I"
         else f"{prefix_str}-MFS-{pol}-residual.fits"
     )
 
     big_image = fits.getdata(mfs_image_name).squeeze()
-    big_model = fits.getdata(mfs_model_name).squeeze()
     big_residual = fits.getdata(mfs_residual_name).squeeze()
+    big_model = big_image - big_residual
 
     small_image = resize(big_image, small_size)
     small_model = resize(big_model, small_size)
@@ -181,14 +177,11 @@ def make_validation_plots(prefix: Path, pols: str) -> None:
     for stokes in pols:
         mfs_image = get_mfs_image(prefix_str, stokes)
         fig, axs = plt.subplots(1, 3, figsize=(15, 5))
-        for ax, sub_image, title in zip(axs, mfs_image, ("Image", "Model", "Residual")):
+        for ax, sub_image, title in zip(
+            axs, mfs_image, ("Image", "Model (conv.)", "Residual")
+        ):
             sub_image = np.abs(sub_image)
-            if title == "Model":
-                norm = ImageNormalize(
-                    sub_image, interval=MinMaxInterval(), stretch=SqrtStretch()
-                )
-            else:
-                norm = ImageNormalize(mfs_image.residual, vmin=0, stretch=SqrtStretch())
+            norm = ImageNormalize(mfs_image.residual, vmin=0, stretch=SqrtStretch())
             _ = ax.imshow(sub_image, origin="lower", norm=norm, cmap="cubehelix")
             ax.set_title(title)
             ax.get_yaxis().set_visible(False)
@@ -280,6 +273,38 @@ def get_prefix(
     return out_dir / prefix
 
 
+def run_wsclean_singuarlity(
+    command: str,
+    simage: Path,
+    out_dir: Path,
+    root_dir: Path,
+) -> None:
+    logger.info(f"Running wsclean with command: {command}")
+    try:
+        output = sclient.execute(
+            image=simage.resolve(strict=True).as_posix(),
+            command=command.split(),
+            bind=f"{out_dir}:{out_dir}, {root_dir.resolve(strict=True).as_posix()}:{root_dir.resolve(strict=True).as_posix()}",
+            return_result=True,
+            quiet=False,
+            stream=True,
+        )
+        for line in output:
+            logger.info(line.rstrip())
+            # Catch divergence - look for the string 'KJy' in the output
+            if "KJy" in line:
+                raise DivergenceError(
+                    f"Detected divergence in wsclean output: {line.rstrip()}"
+                )
+
+    except CalledProcessError as e:
+        logger.error(f"Failed to run wsclean with command: {command}")
+        logger.error(f"Stdout: {e.stdout}")
+        logger.error(f"Stderr: {e.stderr}")
+        logger.error(f"{e=}")
+        raise e
+
+
 @task(name="Image Beam", persist_result=True)
 def image_beam(
     ms: Path,
@@ -423,29 +448,26 @@ def image_beam(
     )
 
     root_dir = ms.parent
-    logger.info(f"Running wsclean with command: {command}")
     try:
-        output = sclient.execute(
-            image=simage.resolve(strict=True).as_posix(),
-            command=command.split(),
-            bind=f"{out_dir}:{out_dir}, {root_dir.resolve(strict=True).as_posix()}:{root_dir.resolve(strict=True).as_posix()}",
-            return_result=True,
-            quiet=False,
-            stream=True,
+        run_wsclean_singuarlity(
+            command=command,
+            simage=simage,
+            out_dir=out_dir,
+            root_dir=root_dir,
+        )
+    except DivergenceError as de:
+        logger.error(f"Detected divergence in wsclean output: {de}")
+        new_pix = npix + 1024
+        new_command = command.replace(f"{npix} {npix}", f"{new_pix} {new_pix}")
+        logger.critical(
+            f"Rerunning wsclean with larger image size: {new_pix}x{new_pix}"
+        )
+        run_wsclean_singuarlity(
+            command=new_command,
+            simage=simage,
+            out_dir=out_dir,
+            root_dir=root_dir,
         )
-        for line in output:
-            logger.info(line.rstrip())
-            # Catch divergence - look for the string 'KJy' in the output
-            if "KJy" in line:
-                raise ValueError(
-                    f"Detected divergence in wsclean output: {line.rstrip()}"
-                )
-    except CalledProcessError as e:
-        logger.error(f"Failed to run wsclean with command: {command}")
-        logger.error(f"Stdout: {e.stdout}")
-        logger.error(f"Stderr: {e.stderr}")
-        logger.error(f"{e=}")
-        raise e
 
     # Purge ms_temp
     shutil.rmtree(ms_temp)

arrakis/utils/exceptions.py

@@ -34,3 +34,7 @@ class ReadError(OSError):
 class RegistryError(Exception):
     """Raised when a registry operation with the archiving
     and unpacking registeries fails"""
+
+
+class DivergenceError(Exception):
+    """Raised when a divergence is detected"""