matlab - 从 Matlab 文件导入时为 "LapackError: Parameter a has non-native byte order in lapack_lite.dgesdd"

Question

导入后this data file从 Matlab 和 scipy.io.loadmat 开始，一切似乎都工作正常，直到我们尝试计算其中一个矩阵的条件数。

这是为我们重现的最少代码量:

import scipy
import numpy

stuff = scipy.io.loadmat("dati-esercizio1.mat")
numpy.linalg.cond(stuff["A"])

这是 iPython 提供的扩展堆栈跟踪:

In [3]: numpy.linalg.cond(A)
---------------------------------------------------------------------------
LapackError                               Traceback (most recent call last)
/snip/<ipython-input-3-15d9ef00a605> in <module>()
----> 1 numpy.linalg.cond(A)

/snip/python2.7/site-packages/numpy/linalg/linalg.py in cond(x, p)
   1409     x = asarray(x) # in case we have a matrix
   1410     if p is None:
-> 1411         s = svd(x,compute_uv=False)
   1412         return s[0]/s[-1]
   1413     else:

/snip/python2.7/site-packages/numpy/linalg/linalg.py in svd(a, full_matrices, compute_uv)
   1313         work = zeros((lwork,), t)
   1314         results = lapack_routine(option, m, n, a, m, s, u, m, vt, nvt,
-> 1315                                  work, -1, iwork, 0)
   1316         lwork = int(work[0])
   1317         work = zeros((lwork,), t)

LapackError: Parameter a has non-native byte order in lapack_lite.dgesdd

所有明显的想法(例如展平和 reshape 矩阵或从头开始重新创建矩阵，逐个元素重新分配)都失败了。那么，我怎样才能对数据进行处理，使其更适合 numpy 呢？

Answer 1

这是一个错误，前段时间已修复:https://github.com/numpy/numpy/pull/235

解决方法:

np.linalg.cond(stuff['A'].newbyteorder('='))