Question

我有以下问题：我使用realines读取一行，该行如下：

参考坐标：外部参照= 0.00000E + 000，Yref = -1.20982E-002

我希望将此行转换为numpy数组，以便：

         array=[nan nan nan nan 0.0 nan nan -1.20982E-002]

比我想要能够访问这个数组：

        number1=array[0][4]
        print(number1)
        0.00000E+000
        number2=array[0][6]
        print(number2)
        -1.20982E-002

问题是当我使用例如np.fromstring（我试过我认为所有类似的numpy例程）我无法像这样访问数组。要么我得到：

        Enter file name: ERIS-NIX_106_-FOLDED-Grid_Distortion-cam2-wl3.txt
        ["['Reference" 'Coordinates:' 'Xref' '=' '0.00000E+000,' 'Yref' '='
         "3.00947E-003\\r\\n']"]
       [

       Traceback (most recent call last):
       File "/home/sebo/Documents/Linear Transform For Eris C1/ERIS-NIX_106_-FOLDED-Grid_Distortion(1)/Open_shift.py", line 51, in <module>
      main()
       File "/home/sebo/Documents/Linear Transform For Eris C1/ERIS-NIX_106_-FOLDED-Grid_Distortion(1)/Open_shift.py", line 9, in main
       reader_affine(file_name,d)
       File "/home/sebo/Documents/Linear Transform For Eris C1/ERIS-    NIX_106_-FOLDED-Grid_Distortion(1)/Open_shift.py", line 35, in reader_affine
       print(line[0][i][i])
       IndexError: string index out of range

或

      Enter file name: ERIS-NIX_106_-FOLDED-Grid_Distortion-cam2-wl3.txt

      Traceback (most recent call last):
      File "/home/sebo/Documents/Linear Transform For Eris C1/ERIS-                 NIX_106_-FOLDED-Grid_Distortion(1)/Open_shift.py",        line 50, in <module>
      main()
      File "/home/sebo/Documents/Linear Transform For Eris C1/ERIS-           NIX_106_-FOLDED-Grid_Distortion(1)/Open_shift.py", line 9, in main
      reader_affine(file_name,d)
      File "/home/sebo/Documents/Linear Transform For Eris C1/ERIS-NIX_106_-FOLDED-Grid_Distortion(1)/Open_shift.py",               line 29, in reader_affine
      line=np.fromstring(critical_line,dtype=float)
      ValueError: string size must be a multiple of element size

或者我可以单独访问我的阵列，但我得到的结果是：

      Enter file name: ERIS-NIX_106_-FOLDED-Grid_Distortion-cam2-wl3.txt
      [
      C
      X
      =
      0
      Y
      =
      3

对于这样的循环：

        while i in range(0,line.size):
        print(line[0][i])
        i=i+1

Answer 1

之前已经问过类似的问题（Python: Extract numbers from a string）。我从问题中复制了你的输入列表（字符串），除了删除双引号。

s=['Reference' 'Coordinates:' 'Xref' '=' '0.00000E+000,' 'Yref' '=''3.00947E-003\\r\\n']

然后你可以先提取删除非数字字符，这会创建一个数字列表作为字符串：

 import re
 x=array(re.findall(r"[+-]? *(?:\d+(?:\.\d*)?|\.\d+)(?:[eE][+-]?\d+)?", s[0]))

输出 ['0.00000E + 000''3.00947E-003']

将其转换为float数组：

import numpy as np
y = x.astype(np.float)
print y

输出： [0. 0.00300947]

从一行创建一个numpy数组

1 个答案: