Get correct catalog length (#26)

src/corrgi/corrgi.py

@@ -5,6 +5,7 @@
 from corrgi.correlation.correlation import Correlation
 from corrgi.dask import compute_autocorrelation_counts
 from corrgi.estimators import calculate_natural_estimate
+from corrgi.utils import compute_catalog_size
 
 
 def compute_autocorrelation(
@@ -24,9 +25,9 @@ def compute_autocorrelation(
     """
     correlation = corr_type(**kwargs)
     correlation.validate([catalog, random])
+    num_galaxies = compute_catalog_size(catalog)
+    num_random = compute_catalog_size(random)
     counts_dd, counts_rr = compute_autocorrelation_counts(catalog, random, correlation)
-    num_galaxies = catalog.hc_structure.catalog_info.total_rows
-    num_random = random.hc_structure.catalog_info.total_rows
     return calculate_natural_estimate(counts_dd, counts_rr, num_galaxies, num_random)
 
 

src/corrgi/utils.py

@@ -1,5 +1,6 @@
 import numpy as np
 from gundam import gundam
+from lsdb import Catalog
 from numpy import deg2rad
 
 
@@ -42,3 +43,15 @@ def join_count_histograms(partial_histograms: list[np.ndarray]) -> np.ndarray:
         The numpy array with the total counts for the partial histograms.
     """
     return np.sum(np.stack(partial_histograms), axis=0)
+
+
+def compute_catalog_size(catalog: Catalog) -> int:
+    """Compute the number of rows in a catalog.
+
+    Args:
+        catalog (Catalog): An LSDB catalog.
+
+    Returns:
+        The number of rows in the catalog.
+    """
+    return catalog._ddf.shape[0].compute()