Question

I have the current script included below that goes into a file with extension .las and replaces certain strings with others (ie.: cat -> kitten, dog -> puppy).

All I want is to add in a functionality into this script that would rename ANY .las file to a certain name in the current directory when I run the script (ie.: *.las -> animals.las).

I would drag a single file into this directory, run the script, which performs the text replacement and the rename and then move the file out of the current directory. So for this script, I don’t care that it would rewrite multiple .las files to a single name.

# read a text file, replace multiple words specified in a dictionary
# write the modified text back to a file

import re
import os
import time

# the dictionary has target_word:replacement_word pairs
word_dic = {
'cat' : 'kitten',
'dog' : 'puppy'
}


def replace_words(text, word_dic):
    """
    take a text and replace words that match a key in a dictionary with
    the associated value, return the changed text
    """
    rc = re.compile('|'.join(map(re.escape, word_dic)))
    def translate(match):
        return word_dic[match.group(0)]
    return rc.sub(translate, text)

def scanFiles(dir): 
    for root, dirs, files in os.walk(dir):
        for file in files:
            if '.las' in file:
            # read the file
                fin = open(file, "r")
                str2 = fin.read()
                fin.close()
            # call the function and get the changed text
                str3 = replace_words(str2, word_dic)
            # write changed text back out
                fout = open(file, "w")
                fout.write(str3)
                fout.close()
                #time.sleep(1)



scanFiles('')

I pasted the script together from online examples so I don’t know all the inner workings of it, so if anyone has a more elegant/efficient way of doing what this script is doing, I am open to changing it.

Answer 1

If you want to end up with a single file named animals.las containing the contents of *.las, then you can change the scanFiles function to open animals.las at the start of the loop, write the translated output of each *.las file to animals.las, and then close animals.las:

def scanFiles(dir): 
    fout = open("animals.las", "w")
    for root, dirs, files in os.walk(dir):
        for file in files:
            if '.las' in file:
            # read the file
                fin = open(file, "r")
                str2 = fin.read()
                fin.close()
            # call the function and get the changed text
                str3 = replace_words(str2, word_dic)
            # write changed text back out
                fout.write(str3)
                #time.sleep(1)
    fout.close()