DOC: sparse.linalg: add two recent functions to namespace and fix doctests (scipy#22374)

* fix doctests and make two recent functions visible

* update refguide

[docs only]

* fix capitalization   [docs only]

Co-authored-by: Daniel Schmitz <40656107+dschmitz89@users.noreply.github.com>

---------

Co-authored-by: Daniel Schmitz <40656107+dschmitz89@users.noreply.github.com>

Author: 2 people

scipy/sparse/linalg/__init__.py

@@ -43,6 +43,8 @@
 
    spsolve -- Solve the sparse linear system Ax=b
    spsolve_triangular -- Solve sparse linear system Ax=b for a triangular A.
+   is_sptriangular -- Check if sparse A is triangular.
+   spbandwidth -- Find the bandwidth of a sparse matrix.
    factorized -- Pre-factorize matrix to a function solving a linear system
    MatrixRankWarning -- Warning on exactly singular matrices
    use_solver -- Select direct solver to use

scipy/sparse/linalg/_dsolve/__init__.py

@@ -62,8 +62,8 @@
 
 __all__ = [
     'MatrixRankWarning', 'SuperLU', 'factorized',
-    'spilu', 'splu', 'spsolve',
-    'spsolve_triangular', 'use_solver'
+    'spilu', 'splu', 'spsolve', 'is_sptriangular',
+    'spsolve_triangular', 'use_solver', 'spbandwidth',
 ]
 
 from scipy._lib._testutils import PytestTester

scipy/sparse/linalg/_dsolve/linsolve.py

@@ -768,11 +768,12 @@ def is_sptriangular(A):
     --------
     >>> import numpy as np
     >>> from scipy.sparse import csc_array, eye_array
+    >>> from scipy.sparse.linalg import is_sptriangular
     >>> A = csc_array([[3, 0, 0], [1, -1, 0], [2, 0, 1]], dtype=float)
-    >>> scipy.sparse.linalg.is_sptriangular(A)
+    >>> is_sptriangular(A)
     (True, False)
-    >>> D = eye_array((3,3), format='csr')
-    >>> scipy.sparse.linalg.is_sptriangular(D)
+    >>> D = eye_array(3, format='csr')
+    >>> is_sptriangular(D)
     (True, True)
     """
     if not (issparse(A) and A.format in ("csc", "csr", "coo", "dia", "dok", "lil")):
@@ -841,12 +842,13 @@ def spbandwidth(A):
     Examples
     --------
     >>> import numpy as np
+    >>> from scipy.sparse.linalg import spbandwidth
     >>> from scipy.sparse import csc_array, eye_array
     >>> A = csc_array([[3, 0, 0], [1, -1, 0], [2, 0, 1]], dtype=float)
-    >>> scipy.sparse.linalg.spbandwidth(A)
+    >>> spbandwidth(A)
     (2, 0)
-    >>> D = eye_array((3,3), format='csr')
-    >>> scipy.sparse.linalg.spbandwidth(D)
+    >>> D = eye_array(3, format='csr')
+    >>> spbandwidth(D)
     (0, 0)
     """
     if not (issparse(A) and A.format in ("csc", "csr", "coo", "dia", "dok")):