Coverage for /pythoncovmergedfiles/medio/medio/usr/local/lib/python3.8/site-packages/scipy/sparse/linalg/_dsolve/__init__.py: 100%

1""" 

2Linear Solvers 

3============== 

4 

5The default solver is SuperLU (included in the scipy distribution), 

6which can solve real or complex linear systems in both single and 

7double precisions. It is automatically replaced by UMFPACK, if 

8available. Note that UMFPACK works in double precision only, so 

9switch it off by:: 

10 

11 >>> use_solver(useUmfpack=False) 

12 

13to solve in the single precision. See also use_solver documentation. 

14 

15Example session:: 

16 

17 >>> from scipy.sparse import csc_matrix, spdiags 

18 >>> from numpy import array 

19 >>> from scipy.sparse.linalg import spsolve, use_solver 

20 >>> 

21 >>> print("Inverting a sparse linear system:") 

22 >>> print("The sparse matrix (constructed from diagonals):") 

23 >>> a = spdiags([[1, 2, 3, 4, 5], [6, 5, 8, 9, 10]], [0, 1], 5, 5) 

24 >>> b = array([1, 2, 3, 4, 5]) 

25 >>> print("Solve: single precision complex:") 

26 >>> use_solver( useUmfpack = False ) 

27 >>> a = a.astype('F') 

28 >>> x = spsolve(a, b) 

29 >>> print(x) 

30 >>> print("Error: ", a@x-b) 

31 >>> 

32 >>> print("Solve: double precision complex:") 

33 >>> use_solver( useUmfpack = True ) 

34 >>> a = a.astype('D') 

35 >>> x = spsolve(a, b) 

36 >>> print(x) 

37 >>> print("Error: ", a@x-b) 

38 >>> 

39 >>> print("Solve: double precision:") 

40 >>> a = a.astype('d') 

41 >>> x = spsolve(a, b) 

42 >>> print(x) 

43 >>> print("Error: ", a@x-b) 

44 >>> 

45 >>> print("Solve: single precision:") 

46 >>> use_solver( useUmfpack = False ) 

47 >>> a = a.astype('f') 

48 >>> x = spsolve(a, b.astype('f')) 

49 >>> print(x) 

50 >>> print("Error: ", a@x-b) 

51 

52""" 

53 

54#import umfpack 

55#__doc__ = '\n\n'.join( (__doc__, umfpack.__doc__) ) 

56#del umfpack 

57 

58from .linsolve import * 

59from ._superlu import SuperLU 

60from . import _add_newdocs 

61from . import linsolve 

62 

63__all__ = [ 

64 'MatrixRankWarning', 'SuperLU', 'factorized', 

65 'spilu', 'splu', 'spsolve', 

66 'spsolve_triangular', 'use_solver' 

67] 

68 

69from scipy._lib._testutils import PytestTester 

70test = PytestTester(__name__) 

71del PytestTester