Optimize python code

Question

I have the following code:

 inputFile = open('C:/Abaqus_JOBS' + JobDir + '/' + JobName + '-3_4.inp', 'r')
 for line in inputFile:
 fileData.append([x.strip() for x in line.split(',')])
 fel=0
 for row,data in enumerate(fileData):
 if data[0]=='*Node':
 row_nodes = row #number of the row when data='*Node'
 if data[0]=='*Element' and fel==0:
 row_elements2 = row
 fel=1
 for row,data in enumerate(fileData[row_nodes + 1:row_elements2]):
 nodes.append(data) #data between '*Nodes' and '*Element'

However, it runs very slow (minutes) in the python interpeter of an external program (I have to run the script here because I need to access a database of results produced by this program). How can I optimize it?

EDIT: I close the inputFile at the end of the code: inputFile.close()

• Patashu: What's in the ....?
• John Lyon: how big is the file? Are you sure you're closing the file properly after reading it?
• jpcgandre: @Patashu, jozzas: question edited.
• Patashu: Are you forced to write it in Python, or are you able to write it in a faster language?
• jpcgandre: @Patashu: I can write in C++.... but I'd have to learn it.

Answer 1

If I understand well, you first store the file line by line, then search for the first occurence of "*Element" and the last occurence of "*Node", and finally store what's between them.

An optimization I see is that you can go from 3 parsing of your file to a single one:

inputFile = open('C:/Abaqus_JOBS' + JobDir + '/' + JobName + '-3_4.inp', 'r')
go_storage = False
nodes = None
for line in inputFile:
 if line[0] == "*Node":
 # Reset what has already been memorized
 nodes = list()
 go_storage = True
 elif line[0] == "*Element":
 break
 elif go_storage:
 nodes.append(line) 

Answer 2

Maybe you could think along the lines of regular expressions:

if I understand it right, you want to get the data between the keywords *Node and *Element in some file, right?

well you could try something like:

import re
S = open('C:/Abaqus_JOBS' + JobDir + '/' + JobName + '-3_4.inp','r').read() 
Data = re.finditer( "\*Nonde([.\n]*?)\*Element", S )

That should give you a list of strings that are found in between the Tags "*Node" and "*Elements"

I hope that was what you were trying to do. Cheers