CODEWITHSUNDEEP
python
AshA
AshA

Reputation: 289

How to compare the modified date of two files in python?

I am creating a python script that will access each line from a Text file(say File.txt) one by one then search for corresponding '.py' and '.txt' file in the system directory. For example if "COPY"(the first line) is accessed from "File.txt" then search will be done for "COPY.py" and "COPY.txt". If both the files are found then their modification date will be compared. Code have no syntax error But I am getting the wrong output.

My Python code is:

for line in fileinput.input(r'D:\Python_Programs\File.txt'):
    line = line[0:-1]
    sc = ''.join((line,'.py'))
    lo = ''.join((line,'.txt'))
    for root, dirs, files in os.walk(r'D:\txt and py'):
        if sc in files:
            pytime = time.ctime(os.path.getmtime(os.path.join(root, sc)))
            print(sc, '   :', pytime)
            for root, dirs, files in os.walk(root):
                if txt in files:
                    txttime = time.ctime(os.path.getmtime(os.path.join(root, txt)))
                    print(txt, '  :', txttime)
                    if (txttime > pytime):
                        print('PASS', '\n')
                    else:
                        print('FAIL', '\n')

Output:

COPY.py     : Mon Aug 27 10:50:06 2012
COPY.txt    : Mon Feb 04 11:05:31 2013
PASS        #Expected = PASS

COPY2.py    : Fri Feb 08 16:34:43 2013
COPY2.txt   : Sat Sep 22 14:19:32 2012
PASS        #Expected = FAIL

COPY3.py    : Fri Feb 08 16:34:53 2013
COPY3.txt   : Mon Sep 24 00:50:07 2012
PASS        #Expected = FAIL

I am not getting why "COPY2" and "COPY3" are giving "PASS". May be I am doing it in a wrong way. As well as on changing the comparison as "if (txttime < pytime)" in the code. All results are showing as "FAIL" in output.

Upvotes: 20

Views: 28945

Answers (3)

Dave X
Dave X

Reputation: 5127

I liked copying the bash file test -nt (newer than) and -ot (older than) logic for use-cases where you might want to test whether to process old files into new files:

def test_file_newer_than(file1,file2):
    """
    True if file1 is newer (according  to  modification date) than
    file2, or if file1 exists and file2 does not.
    (like bash file test operator -nt)
"""
    import os.path
    import datetime
    retval = os.path.exists(file1)
    if retval and os.path.exists(file2):
        mtime1 = os.path.getmtime(file1)
        mtime2 = os.path.getmtime(file2)
        newer = mtime1 - mtime2
        retval = newer > 0 
        #print(F"{mtime1}-{mtime2} = {newer}")
    return retval

def test_file_older_than(file1,file2):
    """
    True if file1 is older (according  to  modification  date)  than
    file2, or if file2 exists and file1 does not.
    (like bash file test operator -nt)
"""
    import os.path
    import datetime
    retval = os.path.exists(file2)
    if retval and os.path.exists(file1):
        mtime1 = os.path.getmtime(file1)
        mtime2 = os.path.getmtime(file2)
        older = mtime2 - mtime1
        retval = older > 0 
        #print(F"{mtime2}-{mtime1} = {older}")
    return retval

Upvotes: 0

millimoose
millimoose

Reputation: 39950

time.ctime() formats a time as a string, so you're comparing the strings "Fri Feb 08 16:34:43 2013" and "Sat Sep 22 14:19:32 2012" textually. Just don't do that and compare the floats that getmtime() gives you directly:

pytime = os.path.getmtime(os.path.join(root, sc))
# ...
txttime = os.path.getmtime(os.path.join(root, txt))
# ...
if (txttime > pytime):
    # ...

Upvotes: 47

wRAR
wRAR

Reputation: 25693

time.ctime returns a string and 'Fri Feb 08 16:34:53 2013' < 'Mon Sep 24 00:50:07 2012'

Upvotes: -1

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