đọc khoa học tập ký hiệu csv với NumPy

Question

Tôi đang cố gắng để tải một tập tin mà đại diện cho một ma trận với loadtxt NumPy 2D

cov = np.loadtxt("cov.csv") 

Yếu tố đầu tiên là trong ký hiệu khoa học gây ra một sự thất bại

--------------------------------------------------------------------------- 
ValueError        Traceback (most recent call last) 
<ipython-input-80-0796abd8c0f7> in <module>() 
----> 1 cov = np.loadtxt("cov.csv") 

C:\home\Anaconda3\lib\site-packages\numpy\lib\npyio.py in loadtxt(fname, dtype, comments, delimiter, converters, skiprows, usecols, unpack, ndmin) 
    858 
    859    # Convert each value according to its column and store 
--> 860    items = [conv(val) for (conv, val) in zip(converters, vals)] 
    861    # Then pack it according to the dtype's nesting 
    862    items = pack_items(items, packing) 

C:\home\Anaconda3\lib\site-packages\numpy\lib\npyio.py in <listcomp>(.0) 
    858 
    859    # Convert each value according to its column and store 
--> 860    items = [conv(val) for (conv, val) in zip(converters, vals)] 
    861    # Then pack it according to the dtype's nesting 
    862    items = pack_items(items, packing) 

ValueError: could not convert string to float: b'5.0e-7,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0' 

Tôi không thể tìm thấy bất kỳ tài liệu nào về cách thực hiện công việc này.

numpy version: 1.9.2 
python version: 3.4.3 |Anaconda 2.3.0 (32-bit)| (default, Mar 6 2015, 12:08:17) [MSC v.1600 32 bit (Intel)] 

Answer 1

Nó không phải là ký hiệu khoa học là vấn đề; đó là dấu phân tách mặc định loadtxt là bất kỳ khoảng trống nào. Bạn đang đọc csv, vì vậy hãy chỉ định delimiter=",":

>>> np.loadtxt("cov.csv") 
Traceback (most recent call last): 
    File "<ipython-input-1-6fdfa7467ef5>", line 1, in <module> 
    np.loadtxt("cov.csv") 
    File "/usr/local/lib/python3.4/dist-packages/numpy/lib/npyio.py", line 928, in loadtxt 
    items = [conv(val) for (conv, val) in zip(converters, vals)] 
    File "/usr/local/lib/python3.4/dist-packages/numpy/lib/npyio.py", line 928, in <listcomp> 
    items = [conv(val) for (conv, val) in zip(converters, vals)] 
    File "/usr/local/lib/python3.4/dist-packages/numpy/lib/npyio.py", line 659, in floatconv 
    return float(x) 
ValueError: could not convert string to float: b'5.0e-7,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0' 

>>> np.loadtxt("cov.csv", delimiter=",") 
array([ 5.00000000e-07, 0.00000000e+00, 0.00000000e+00, 
     0.00000000e+00, 0.00000000e+00, 0.00000000e+00, 
     0.00000000e+00, 0.00000000e+00, 0.00000000e+00, 
     0.00000000e+00, 0.00000000e+00, 0.00000000e+00, 
     0.00000000e+00, 0.00000000e+00, 0.00000000e+00, 
     0.00000000e+00, 0.00000000e+00, 0.00000000e+00, 
     0.00000000e+00, 0.00000000e+00, 0.00000000e+00, 
     0.00000000e+00, 0.00000000e+00, 0.00000000e+00, 
     0.00000000e+00, 0.00000000e+00, 0.00000000e+00, 
     0.00000000e+00, 0.00000000e+00, 0.00000000e+00, 
     0.00000000e+00, 0.00000000e+00, 0.00000000e+00, 
     0.00000000e+00, 0.00000000e+00, 0.00000000e+00, 
     0.00000000e+00, 0.00000000e+00, 0.00000000e+00, 
     0.00000000e+00, 0.00000000e+00, 0.00000000e+00, 
     0.00000000e+00, 0.00000000e+00, 0.00000000e+00, 
     0.00000000e+00, 0.00000000e+00, 0.00000000e+00, 
     0.00000000e+00, 0.00000000e+00, 0.00000000e+00, 
     0.00000000e+00, 0.00000000e+00, 0.00000000e+00])