Python Numpy ndarray从文本跳过行 [英] Python numpy ndarray skipping lines from text

问题描述

基于此答案，我正在使用changethis方法

import numpy as np
import os

def changethis(pos):
    appex = sfile[pos[1]-1][:pos[2]] + '*' + file[pos[1]-1][pos[2]+len(pos[0]):]
    file[pos[1]-1] = appex

pos = ('stack', 3, 16)
sfile = np.genfromtxt('in.cpp',dtype='str',delimiter=os.linesep)
changethis(pos)
print(file)

其中in.cpp是包含以下内容的源文件:

where the in.cpp is a source file which contains the following:

/* Multi-line 
comment
*/

#include <iostream>
#include <fstream>

using namespace std;

int main (int argc, char *argv[]) {
  int linecount = 0;
  double array[1000], sum=0, median=0, add=0;
  string filename;
  if (argc <= 1)
      {
          cout << "Error" << endl;
          return 0;
      }

我得到输出:

['using namespace std;' 'int main (int argc, char *argv[]) {'
 'int linecount = *' 'double array[1000], sum=0, median=0, add=0;'
 'string filename;' 'if (argc <= 1)' '{' 'cout << "Error" << endl;'
 'return 0;' '}']

请注意，ndarray中缺少多行注释， include语句和空行

我不明白为什么会发生这种情况，因为delimiter设置为考虑到每个换行字符.

I do not understand why this happens since the delimiter is set to account for each change-of-line character.

关于如何输出的任何建议:

Any suggestions on how the output to be:

['/* Multi-line' 'comment' '*/' '' '#include <iostream>',
 '' '#include <fstream>' '' 'using namespace std;'
 '' 'int main (int argc, char *argv[]) {'
 'int linecount = *' 'double array[1000], sum=0, median=0, add=0;'
 'string filename;' 'if (argc <= 1)' '{' 'cout << "Error" << endl;'
 'return 0;' '}']

推荐答案

再次抱歉使用genfromtxt，不理解您的意图，只是尝试为该问题提供可能的解决方案.作为该特定解决方案(已提供其他解决方案)的后续操作，您可以执行以下操作:

Again sorry for the use of genfromtxt, didn't understood your intentions, just tried to provide a possible solution for the problem. As a follow up for that particular solution (others have been provided) you can just do:

import numpy as np
import os

def changethis(pos):
    # Notice file is in global scope
    appex = file[pos[1]-1][:pos[2]] + '*' + file[pos[1]-1][pos[2]+len(pos[0]):]
    file[pos[1]-1] = appex

pos = ('stack', 3, 16)
file = np.array([i for i in open('in.txt','r')]) # instead of genfromtext.
changethis(pos)
print(file)

，导致:

['/* Multi-line \n' 'comment\n' '*/\n*' '\n' '#include <iostream>\n'
 '#include <fstream>\n' '\n' 'using namespace std;\n' '\n'
 'int main (int argc, char *argv[]) {\n' '  int linecount = 0;\n'
 '  double array[1000], sum=0, median=0, add=0;\n' '  string filename;\n'
 '  if (argc <= 1)\n' '      {\n' '          cout << "Error" << endl;\n'
 '          return 0;\n' '      }']

另外，另一个用户提到的另一个要点是我用于文件的范围.我并不是要告诉您在全局范围内进行操作，而是要解释该功能正在工作，因为文件在全局范围内.无论如何，您都可以创建一个函数来保存范围:

Also another relevant point mentioned by another user is the scope I was using for file. I did not mean to tell you to do stuff in global scope, I meant to explain that the function was working because file was in global scope. In any case you can create a function to hold the scope:

import numpy as np
import os

def changeallthese(poslist,path):
    def changethis(pos):
        appex = file[pos[1]-1][:pos[2]-1] + '*' + file[pos[1]-1][pos[2]-1+len(pos[0]):]
        file[pos[1]-1] = appex
    file = np.array([str(i) for i in open(path,'r')])
    for i in poslist:
        changethis(i)
    return file

poslist = [('stack', 3, 16),('stack', 18, 1),('/* Multi-line', 1, 1)]
file =   changeallthese(poslist,'in.txt')
print(file)

，结果为:

['* \n' 'comment\n' '*/\n*' '\n' '#include <iostream>\n'
 '#include <fstream>\n' '\n' 'using namespace std;\n' '\n'
 'int main (int argc, char *argv[]) {\n' '  int linecount = 0;\n'
 '  double array[1000], sum=0, median=0, add=0;\n' '  string filename;\n'
 '  if (argc <= 1)\n' '      {\n' '          cout << "Error" << endl;\n'
 '          return 0;\n' '* }']

要向文件写入数组，您可以使用Python中的常规文件写入系统:

To write an array to file you can either use the normal file writing system in Python:

fid = open('out.txt','w')
fid.writelines(file)
fid.close()

，或者使用numpy中的函数(但是我不确定它是否会添加更多的结尾行，所以请小心):

, or use a function from numpy (but I'm not sure if it will add more endlines or not so be careful):

np.savetxt('out.txt',file,fmt='%s')

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