File Content: lapack.py """ Low-level LAPACK functions (:mod:`scipy.linalg.lapack`) ======================================================= This module contains low-level functions from the LAPACK library. The `*gegv` family of routines have been removed from LAPACK 3.6.0 and have been deprecated in SciPy 0.17.0. They will be removed in a future release. .. versionadded:: 0.12.0 .. warning:: These functions do little to no error checking. It is possible to cause crashes by mis-using them, so prefer using the higher-level routines in `scipy.linalg`. Finding functions ----------------- .. autosummary:: get_lapack_funcs All functions ------------- .. autosummary:: :toctree: generated/ sgbsv dgbsv cgbsv zgbsv sgbtrf dgbtrf cgbtrf zgbtrf sgbtrs dgbtrs cgbtrs zgbtrs sgebal dgebal cgebal zgebal sgees dgees cgees zgees sgeev dgeev cgeev zgeev sgeev_lwork dgeev_lwork cgeev_lwork zgeev_lwork sgegv dgegv cgegv zgegv sgehrd dgehrd cgehrd zgehrd sgehrd_lwork dgehrd_lwork cgehrd_lwork zgehrd_lwork sgelss dgelss cgelss zgelss sgelss_lwork dgelss_lwork cgelss_lwork zgelss_lwork sgelsd dgelsd cgelsd zgelsd sgelsd_lwork dgelsd_lwork cgelsd_lwork zgelsd_lwork sgelsy dgelsy cgelsy zgelsy sgelsy_lwork dgelsy_lwork cgelsy_lwork zgelsy_lwork sgeqp3 dgeqp3 cgeqp3 zgeqp3 sgeqrf dgeqrf cgeqrf zgeqrf sgerqf dgerqf cgerqf zgerqf sgesdd dgesdd cgesdd zgesdd sgesdd_lwork dgesdd_lwork cgesdd_lwork zgesdd_lwork sgesvd dgesvd cgesvd zgesvd sgesvd_lwork dgesvd_lwork cgesvd_lwork zgesvd_lwork sgesv dgesv cgesv zgesv sgetrf dgetrf cgetrf zgetrf sgetri dgetri cgetri zgetri sgetri_lwork dgetri_lwork cgetri_lwork zgetri_lwork sgetrs dgetrs cgetrs zgetrs sgges dgges cgges zgges sggev dggev cggev zggev chbevd zhbevd chbevx zhbevx cheev zheev cheevd zheevd cheevr zheevr chegv zhegv chegvd zhegvd chegvx zhegvx slarf dlarf clarf zlarf slarfg dlarfg clarfg zlarfg slartg dlartg clartg zlartg slasd4 dlasd4 slaswp dlaswp claswp zlaswp slauum dlauum clauum zlauum spbsv dpbsv cpbsv zpbsv spbtrf dpbtrf cpbtrf zpbtrf spbtrs dpbtrs cpbtrs zpbtrs sposv dposv cposv zposv spotrf dpotrf cpotrf zpotrf spotri dpotri cpotri zpotri spotrs dpotrs cpotrs zpotrs crot zrot strsyl dtrsyl ctrsyl ztrsyl strtri dtrtri ctrtri ztrtri strtrs dtrtrs ctrtrs ztrtrs cunghr zunghr cungqr zungqr cungrq zungrq cunmqr zunmqr sgtsv dgtsv cgtsv zgtsv sptsv dptsv cptsv zptsv slamch dlamch sorghr dorghr sorgqr dorgqr sorgrq dorgrq sormqr dormqr ssbev dsbev ssbevd dsbevd ssbevx dsbevx ssyev dsyev ssyevd dsyevd ssyevr dsyevr ssygv dsygv ssygvd dsygvd ssygvx dsygvx slange dlange clange zlange ilaver """ # # Author: Pearu Peterson, March 2002 # from __future__ import division, print_function, absolute_import __all__ = ['get_lapack_funcs'] import numpy as _np from .blas import _get_funcs # Backward compatibility: from .blas import find_best_blas_type as find_best_lapack_type from scipy.linalg import _flapack try: from scipy.linalg import _clapack except ImportError: _clapack = None # Backward compatibility from scipy._lib._util import DeprecatedImport as _DeprecatedImport clapack = _DeprecatedImport("scipy.linalg.blas.clapack", "scipy.linalg.lapack") flapack = _DeprecatedImport("scipy.linalg.blas.flapack", "scipy.linalg.lapack") # Expose all functions (only flapack --- clapack is an implementation detail) empty_module = None from scipy.linalg._flapack import * del empty_module _dep_message = """The `*gegv` family of routines has been deprecated in LAPACK 3.6.0 in favor of the `*ggev` family of routines. The corresponding wrappers will be removed from SciPy in a future release.""" cgegv = _np.deprecate(cgegv, old_name='cgegv', message=_dep_message) dgegv = _np.deprecate(dgegv, old_name='dgegv', message=_dep_message) sgegv = _np.deprecate(sgegv, old_name='sgegv', message=_dep_message) zgegv = _np.deprecate(zgegv, old_name='zgegv', message=_dep_message) # Modyfy _flapack in this scope so the deprecation warnings apply to # functions returned by get_lapack_funcs. _flapack.cgegv = cgegv _flapack.dgegv = dgegv _flapack.sgegv = sgegv _flapack.zgegv = zgegv # some convenience alias for complex functions _lapack_alias = { 'corghr': 'cunghr', 'zorghr': 'zunghr', 'corghr_lwork': 'cunghr_lwork', 'zorghr_lwork': 'zunghr_lwork', 'corgqr': 'cungqr', 'zorgqr': 'zungqr', 'cormqr': 'cunmqr', 'zormqr': 'zunmqr', 'corgrq': 'cungrq', 'zorgrq': 'zungrq', } def get_lapack_funcs(names, arrays=(), dtype=None): """Return available LAPACK function objects from names. Arrays are used to determine the optimal prefix of LAPACK routines. Parameters ---------- names : str or sequence of str Name(s) of LAPACK functions without type prefix. arrays : sequence of ndarrays, optional Arrays can be given to determine optimal prefix of LAPACK routines. If not given, double-precision routines will be used, otherwise the most generic type in arrays will be used. dtype : str or dtype, optional Data-type specifier. Not used if `arrays` is non-empty. Returns ------- funcs : list List containing the found function(s). Notes ----- This routine automatically chooses between Fortran/C interfaces. Fortran code is used whenever possible for arrays with column major order. In all other cases, C code is preferred. In LAPACK, the naming convention is that all functions start with a type prefix, which depends on the type of the principal matrix. These can be one of {'s', 'd', 'c', 'z'} for the numpy types {float32, float64, complex64, complex128} respectevely, and are stored in attribute `typecode` of the returned functions. """ return _get_funcs(names, arrays, dtype, "LAPACK", _flapack, _clapack, "flapack", "clapack", _lapack_alias) def _compute_lwork(routine, *args, **kwargs): """ Round floating-point lwork returned by lapack to integer. Several LAPACK routines compute optimal values for LWORK, which they return in a floating-point variable. However, for large values of LWORK, single-precision floating point is not sufficient to hold the exact value --- some LAPACK versions (<= 3.5.0 at least) truncate the returned integer to single precision and in some cases this can be smaller than the required value. """ wi = routine(*args, **kwargs) if len(wi) < 2: raise ValueError('') info = wi[-1] if info != 0: raise ValueError("Internal work array size computation failed: " "%d" % (info,)) lwork = [w.real for w in wi[:-1]] dtype = getattr(routine, 'dtype', None) if dtype == _np.float32 or dtype == _np.complex64: # Single-precision routine -- take next fp value to work # around possible truncation in LAPACK code lwork = _np.nextafter(lwork, _np.inf, dtype=_np.float32) lwork = _np.array(lwork, _np.int64) if _np.any(_np.logical_or(lwork < 0, lwork > _np.iinfo(_np.int32).max)): raise ValueError("Too large work array required -- computation cannot " "be performed with standard 32-bit LAPACK.") lwork = lwork.astype(_np.int32) if lwork.size == 1: return lwork[0] return lwork Submit