Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Welcome To Ask or Share your Answers For Others

Categories

0 votes
190 views
in Technique[技术] by (71.8m points)

python - Fastest Text search method in a large text file

I am doing a text search in a rather big txt file (100k lines, 7mo) Text is not that big but I need a lot of searches. I want to look for a target string and return the line where it appears. My text file is formatted so that the target can only appear in one line.

What is the most efficient way? I do a lot of searches so I want to improve speed. Here is mycode right now:

def lookup_line(target):
    #returns line of the target, or None if doesnt exist
    line=None
    dir=os.path.dirname(__file__)
    path=dir+'/file.txt'
    file=open(path,'r')
    while line==None:
        l=file.readline()
        l=unicode(l,'utf-8')
        if target in l:
            break
        if l=='': break #happens at end of file, then stop loop
    line=l
    if line=='':line=None #end of file, nothing has been found
    file.close()
    return line

I use this python code for a google Appengine app.

Thanks!

See Question&Answers more detail:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Reply

0 votes
by (71.8m points)
Waitting for answers

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
OGeek|极客中国-欢迎来到极客的世界,一个免费开放的程序员编程交流平台!开放,进步,分享!让技术改变生活,让极客改变未来! Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Click Here to Ask a Question

...