Question

我已经阅读了其他类似帖子，但它们似乎不适用于我的情况。因此，我在这里新发布。

我有一个文本文件，其行和列大小各不相同。我对具有特定参数的值行感兴趣。例如。在下面的示例文本文件中，我希望每行的最后两个值具有数字＆＃39; 1＆＃39;在第二个位置。也就是说，我想要的值是＆＃1; 101＆＃39;，＆＃39; 101,2＆＃39;，＆＃39; 2,102＆＃39;和＆＃103; 102,3＆＃39;从以＃101,101到104＆＃39;值开头的行开头因为他们有数字＆＃39; 1＆＃39;在第二个位置。

$MeshFormat
2.2 0 8
$EndMeshFormat
$Nodes
425
.
.
$EndNodes
$Elements
630
.
97 15 2 0 193 97
98 15 2 0 195 98
99 15 2 0 197 99
100 15 2 0 199 100
101 1 2 0 201 1 101
102 1 2 0 201 101 2
103 1 2 0 202 2 102
104 1 2 0 202 102 3
301 2 2 0 303 178 78 250
302 2 2 0 303 250 79 178
303 2 2 0 303 198 98 249
304 2 2 0 303 249 99 198
.
.
.
$EndElements

问题是，根据我在下面提到的代码，它从＆＃39; 101＆＃39;开始。但它会读取其他行中的值，直到“304”和“304”。或者更多。我做错了什么或有人有更好的方法解决这个问题？

# Here, (additional_lines + anz_knoten_gmsh - 2) are additional lines that need to be skipped 
# at the beginning of the .txt file. Initially I find out where the range 
# of the lines lies which I need.
# The two_noded_elem_start is the first line having the '1' at the second position
# and four_noded_elem_start is the first line number having '2' in the second position. 
# So, basically I'm reading between these two parameters.


input_file = open(os.path.join(gmsh_path, "mesh_outer_region.msh"))
output_file = open(os.path.join(gmsh_path, "mesh_skip_nodes.txt"), "w")

for i, line in enumerate(input_file):                                                
    if i == (additional_lines + anz_knoten_gmsh + two_noded_elem_start - 2):         
        break

for i, line in enumerate(input_file):                                               
    if i == additional_lines + anz_knoten_gmsh + four_noded_elem_start - 2:         
        break

    elem_list = line.strip().split()                
    del elem_list[:5]                               
    writer = csv.writer(output_file)               
    writer.writerow(elem_list)                      

input_file.close()
output_file.close()

*编辑：用于查找像two_noded_elem_start这样的参数的代码如下：

# anz_elemente_ueberg_gmsh is another parameter that is found out 
# from a previous piece of code and '$EndElements' is what 
# is at the end of the text file "mesh_outer_region.msh".

input_file = open(os.path.join(gmsh_path, "mesh_outer_region.msh"), "r")
for i, line in enumerate(input_file):                     
    if line.strip() == anz_elemente_ueberg_gmsh:
        break

for i, line in enumerate(input_file):                    
    if line.strip() == '$EndElements':                    
        break

    element_list = line.strip().split()                   
    if element_list[1] == '1':                            


        two_noded_elem_start = element_list[0]                       
        two_noded_elem_start = int(two_noded_elem_start)            
        break
input_file.close()

Answer 1

>>> with open('filename') as fh:             # Open the file
...    for line in fh:                       # For each line the file
...        values = line.split()             # Split the values into a list
...        if values[1] == '1':              # Compare the second value
...            print values[-2], values[-1]  # Print the 2nd from last and last
1 101
101 2
2 102
102 3

在python

1 个答案: