added read_hp_mask

Author: martinkilbinger

cs_util/cat.py

@@ -11,6 +11,7 @@
 import os
 from datetime import datetime
 from importlib.metadata import version
+import healpy as hp
 
 from astropy.io import fits
 from astropy.io import ascii
@@ -267,3 +268,40 @@ def read_dndz(file_path):
     z_centers = bin_edges2centers(z_edges)
 
     return z_centers, nz, z_edges
+
+
+def read_hp_mask(input_name, verbose=False):
+
+    if verbose:
+        print(f'Reading mask {input_name}...')
+
+    nest = False
+
+    # Open input mask                                                           
+    mask, header= hp.read_map(
+        input_name,
+        h=True,
+        nest=nest,
+    )
+    for (key, value) in header:
+        if key == 'ORDERING':
+            if value == 'RING':
+                if nest:
+                    raise ValueError(
+                        'input mask has ORDENING=RING, set nest to False'
+                    )
+            elif value == 'NEST':
+                if not nest:
+                    raise ValueError(
+                        'input mask has ORDENING=NEST, set nest to True'
+                    )
+
+    # Get nside from header                                                     
+    nside = None
+    for key, value in header:
+        if key == 'NSIDE':
+            nside = int(value)
+    if not nside:
+        raise KeyError('NSIDE not found in FITS mask header')
+
+    return mask, nest, nside

pyproject.toml

@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "cs_util"
-version = "0.1.4"
+version = "0.1.5"
 description = "Utility library for CosmoStat"
 authors = ["Martin Kilbinger <martin.kilbinger@cea.fr>"]
 readme = "README.md"