Fixed database typo and removed unnecessary class identifier.

venv/Lib/site-packages/scipy/sparse/csgraph/_validation.py

@@ -0,0 +1,56 @@
+import numpy as np
+from scipy.sparse import csr_matrix, isspmatrix, isspmatrix_csc
+from ._tools import csgraph_to_dense, csgraph_from_dense,\
+    csgraph_masked_from_dense, csgraph_from_masked
+
+DTYPE = np.float64
+
+
+def validate_graph(csgraph, directed, dtype=DTYPE,
+                   csr_output=True, dense_output=True,
+                   copy_if_dense=False, copy_if_sparse=False,
+                   null_value_in=0, null_value_out=np.inf,
+                   infinity_null=True, nan_null=True):
+    """Routine for validation and conversion of csgraph inputs"""
+    if not (csr_output or dense_output):
+        raise ValueError("Internal: dense or csr output must be true")
+
+    # if undirected and csc storage, then transposing in-place
+    # is quicker than later converting to csr.
+    if (not directed) and isspmatrix_csc(csgraph):
+        csgraph = csgraph.T
+
+    if isspmatrix(csgraph):
+        if csr_output:
+            csgraph = csr_matrix(csgraph, dtype=DTYPE, copy=copy_if_sparse)
+        else:
+            csgraph = csgraph_to_dense(csgraph, null_value=null_value_out)
+    elif np.ma.isMaskedArray(csgraph):
+        if dense_output:
+            mask = csgraph.mask
+            csgraph = np.array(csgraph.data, dtype=DTYPE, copy=copy_if_dense)
+            csgraph[mask] = null_value_out
+        else:
+            csgraph = csgraph_from_masked(csgraph)
+    else:
+        if dense_output:
+            csgraph = csgraph_masked_from_dense(csgraph,
+                                                copy=copy_if_dense,
+                                                null_value=null_value_in,
+                                                nan_null=nan_null,
+                                                infinity_null=infinity_null)
+            mask = csgraph.mask
+            csgraph = np.asarray(csgraph.data, dtype=DTYPE)
+            csgraph[mask] = null_value_out
+        else:
+            csgraph = csgraph_from_dense(csgraph, null_value=null_value_in,
+                                         infinity_null=infinity_null,
+                                         nan_null=nan_null)
+
+    if csgraph.ndim != 2:
+        raise ValueError("compressed-sparse graph must be 2-D")
+
+    if csgraph.shape[0] != csgraph.shape[1]:
+        raise ValueError("compressed-sparse graph must be shape (N, N)")
+
+    return csgraph