Develop Reference

So I just created a text file and copied text from an already existing file using a with loop. How do I open newly created file in same prog?

I'm making a program that takes text from an input file, then you input a file where it copies the already existing file text. Then, I need to replace a few words there and print the count of how many of these words were replaced. This is my code so far, but since with loops close the newly created file, I have no idea how to open it back again for reading and writing and counting. This is my awful code so far:
filename=input("Sisesta tekstifaili nimi: ")
inputFile=open(filename, "r")
b=input("Sisesta uue tekstifaili nimi: ")
uusFail=open(b+".txt", "w+")
f=uusFail
with inputFile as input:
with uusFail as output:
for line in input:
output.write(line)
lines[]
asendus = {'hello':'tere', 'Hello':'Tere'}
with uusFail as infile
for line in infile
for src, target in asendus
line = line, replace(src, target)
lines.append(line)
with uusFail as outfile:
for line in lines:
outfile.write(line)

There are a lot of unnecessary loops in your code. when you read the file, you can treat it as a whole and count the number of occurrences and replace them. Here is a modified version of your code:
infile = input('Enter file name: ')
outfile = input('enter out file: ')
with open(infile) as f:
content = f.read()
asendus = {'hello':'tere', 'Hello':'Tere'}
my_count = 0
for src, target in asendus.items():
my_count += content.count(src)
content = content.replace(src, target)
with open(f'{outfile}.txt','w+' ) as f:
f.write(content)

You need to reopen the file in the second block of code:
with open(b+".txt", "r") as infile:

Remove a word from a file

I am try to sort through the following file
Fantasy
Supernatural
Fantasy
UrbanFantasy
Fantasy
EpicFantasy
Fantasy
HighFantasy
I want to remove the word fantasy when it appears by itself and put the new list into another file
I tried
def getRidofFantasy():
file = open("FantasyGenres.txt", "r")
new_file = open("genres/fantasy", "w")
for line in file:
if line != "Fantasy":
new_file.write(line)
file.close()
new_file.close()
This does not work and I am at a lost as to why. The new file is the same as the old one. Can anyone explain what's happening and give an example of the correct solution?

Try this
with open('fantasy.txt') as f, open('generes/fantasy', 'w') as nf:
lines = [line+'\n' for line in f.read().splitlines() if line != "Fantasy"]
nf.writelines(lines)
In your code when you do for line in f the line variable also include the \n (endline) char, that's why it doesn't work.

Try this. -
def getRidofFantasy():
with open("FantasyGenres.txt", "r") as file:
content = [line.strip('\n') for line in file.readlines()]
new_list = list(filter(lambda a: a != 'Fantasy', content))
with open("genres/fantasy.txt", "w") as new_file:
[new_file.write(f'{line}\n') for line in new_list]
getRidofFantasy()

Similar to #Atin's answer, you can also do this:
with open('fantasy.txt') as f, open('generes/fantasy', 'w') as nf:
lines = [line for line in f.readlines() if line.strip() != "Fantasy"]
nf.writelines(lines)

That is because a new line is also a character:
Fantasy\n
Supernatural\n
etc.
You have to account for that. One possibility:
def getRidofFantasy():
with open("FantasyGenres.txt", "r") as f: # this way Python closes the file buffer for you
oldfile = f.readlines()
new_file = open("genres/fantasy", "w")
for line in oldfile:
line = line.rstrip('\n')
if line != "Fantasy":
new_file.write(line+'\n') # make sure to append the newline character again
new_file.close()

Okay so there is one thing you should know. When you read a line like that the variable will look something like this:-
line='Fantasy\n'
So, you need to strip that character. The simple solution without changing any of your code would be to just change the if statement. Change it to
if not 'Fantasy'== line.strip() and keep your code as it is and the new file that'll be generated will be the one you want.

writing output on file doesn't work in python

I have the code below to write out a list of N-grams in Python.
from nltk.util import ngrams
def word_grams(words, min=1, max=6):
s = []
for n in range(min, max):
for ngram in ngrams(words, n):
s.append(' '.join(str(i) for i in ngram))
return s
email = open("output.txt", "r")
for line in email.readlines():
with open('file.txt', 'w') as f:
for line in email:
prnt = word_grams(email.split(' '))
f.write("prnt")
email.close()
f.close()
when I print out the word_grams it prints out the files correctly but when it comes to writing the output into files.txt it doesn't work. The "file.txt" is empty.
So I guess the problem must be within these lines of codes:
for line in email.readlines():
with open('file.txt', 'w') as f:
for line in email:
prnt = word_grams(email.split(' '))
f.write("prnt")
email.close()
f.close()

1) the final f.close() does something else than what you want (f inside the loop is another object)
2) You name the file "file.txt" but want the output in "files.txt". Are you sure that you are looking in a correct file?
3) You are overwriting the file for each line in the email. Perhaps the with statement for "file.txt" should be outside the loop.
4) You are writing "prnt" instead of prnt
Something like this?
def word_grams(words, min=1, max=6):
s = []
for n in range(min, max):
for ngram in ngrams(words, n):
s.append(' '.join(str(i) for i in ngram))
return s
with open("output.txt", "r") as email:
with open('file.txt', 'w') as f:
for line in email.readlines():
prnt = word_grams(line.split(' '))
for ngram in prnt:
f.write(ngram)

I don't know what you are trying to accomplish exactly, but it seems that you would like to apply the function word_grams to every word in the file "output.txt" and save the output to a file called "file.txt", probably one item per line.
With these assumptions, I would recommend to rewrite your iteration in this manner:
words = []
# load words from input
with open("output.txt") as f:
for line in f:
words += line.strip().split(" ")
# generate and save output
grams = apply(word_grams, words)
with open("file.txt", "w") as f:
f.write("\n".join(grams))
However, this code assumes that the function word_grams is working properly.

Your code in loop:
for line in email:
did not run!
Because after email.readlines()run,the variable email is empty.
You can do some test like fallows:
email = open("output.txt", "r")
for line in email.readlines():
print '1'
for line in email:
print '2'
if you have 3 lines in your output.txt,after you run this test,you will get:
1
1
1
in the output.
And you can do a test like this:
email = open("output.txt", "r")
email.readlines()
you will see a list with the lines in your output.txt.
but when you run email.readlines()again,you will get an empty list!
so,there should be the problem.your variable email is empty in your second loop.

Python search a file for text using input from another file

I'm new to python and programming. I need some help with a python script. There are two files each containing email addresses (more than 5000 lines). Input file contains email addresses that I want to search in the data file(also contains email addresses). Then I want to print the output to a file or display on the console. I search for scripts and was able to modify but I'm not getting the desired results. Can you please help me?
dfile1 (50K lines)
yyy#aaa.com
xxx#aaa.com
zzz#aaa.com
ifile1 (10K lines)
ccc#aaa.com
vvv#aaa.com
xxx#aaa.com
zzz#aaa.com
Output file
xxx#aaa.com
zzz#aaa.com
datafile = 'C:\\Python27\\scripts\\dfile1.txt'
inputfile = 'C:\\Python27\\scripts\\ifile1.txt'
with open(inputfile, 'r') as f:
names = f.readlines()
outputlist = []
with open(datafile, 'r') as fd:
for line in fd:
name = fd.readline()
if name[1:-1] in names:
outputlist.append(line)
else:
print "Nothing found"
print outputlist
New Code
with open(inputfile, 'r') as f:
names = f.readlines()
outputlist = []
with open(datafile, 'r') as f:
for line in f:
name = f.readlines()
if name in names:
outputlist.append(line)
else:
print "Nothing found"
print outputlist

Maybe I'm missing something, but why not use a pair of sets?
#!/usr/local/cpython-3.3/bin/python
data_filename = 'dfile1.txt'
input_filename = 'ifile1.txt'
with open(input_filename, 'r') as input_file:
input_addresses = set(email_address.rstrip() for email_address in input_file.readlines())
with open(data_filename, 'r') as data_file:
data_addresses = set(email_address.rstrip() for email_address in data_file.readlines())
print(input_addresses.intersection(data_addresses))

mitan8 gives the problem you have, but this is what I would do instead:
with open(inputfile, "r") as f:
names = set(i.strip() for i in f)
output = []
with open(datafile, "r") as f:
for name in f:
if name.strip() in names:
print name
This avoids reading the larger datafile into memory.
If you want to write to an output file, you could do this for the second with statement:
with open(datafile, "r") as i, open(outputfile, "w") as o:
for name in i:
if name.strip() in names:
o.write(name)

Here's what I would do:
names=[]
outputList=[]
with open(inputfile) as f:
for line in f:
names.append(line.rstrip("\n")
myEmails=set(names)
with open(outputfile) as fd, open("emails.txt", "w") as output:
for line in fd:
for name in names:
c=line.rstrip("\n")
if name in myEmails:
print name #for console
output.write(name) #for writing to file

I think your issue stems from the following:
name = fd.readline()
if name[1:-1] in names:
name[1:-1] slices each email address so that you skip the first and last characters. While it might be good in general to skip the last character (a newline '\n'), when you load the name database in the "dfile"
with open(inputfile, 'r') as f:
names = f.readlines()
you are including newlines. So, don't slice the names in the "ifile" at all, i.e.
if name in names:

I think you can remove name = fd.readline() since you've already got the line in the for loop. It'll read another line in addition to the for loop, which reads one line every time. Also, I think name[1:-1] should be name, since you don't want to strip the first and last character when searching. with automatically closes the files opened.
PS: How I'd do it:
with open("dfile1") as dfile, open("ifile") as ifile:
lines = "\n".join(set(dfile.read().splitlines()) & set(ifile.read().splitlines())
print(lines)
with open("ofile", "w") as ofile:
ofile.write(lines)
In the above solution, basically I'm taking the union (elements part of both sets) of the lines of both the files to find the common lines.

Match the last word and delete the entire line

Input.txt File
12626232 : Bookmarks
1321121:
126262
Here 126262: can be anything text or digit, so basically will search for last word is : (colon) and delete the entire line
Output.txt File
12626232 : Bookmarks
My Code:
def function_example():
fn = 'input.txt'
f = open(fn)
output = []
for line in f:
if not ":" in line:
output.append(line)
f.close()
f = open(fn, 'w')
f.writelines(output)
f.close()
Problem: When I match with : it remove the entire line, but I just want to check if it is exist in the end of line and if it is end of the line then only remove the entire line.
Any suggestion will be appreciated. Thanks.
I saw as following but not sure how to use it in here
a = "abc here we go:"
print a[:-1]

I believe with this you should be able to achieve what you want.
with open(fname) as f:
lines = f.readlines()
for line in lines:
if not line.strip().endswith(':'):
print line
Here fname is the variable pointing to the file location.

You were almost there with your function. You were checking if : appears anywhere in the line, when you need to check if the line ends with it:
def function_example():
fn = 'input.txt'
f = open(fn)
output = []
for line in f:
if not line.strip().endswith(":"): # This is what you were missing
output.append(line)
f.close()
f = open(fn, 'w')
f.writelines(output)
f.close()
You could have also done if not line.strip()[:-1] == ':':, but endswith() is better suited for your use case.
Here is a compact way to do what you are doing above:
def function_example(infile, outfile, limiter=':'):
''' Filters all lines in :infile: that end in :limiter:
and writes the remaining lines to :outfile: '''
with open(infile) as in, open(outfile,'w') as out:
for line in in:
if not line.strip().endswith(limiter):
out.write(line)
The with statement creates a context and automatically closes files when the block ends.

To search if the last letter is : Do following
if line.strip().endswith(':'):
...Do Something...

You can use a regular expression
import re
#Something end with ':'
regex = re.compile('.(:+)')
new_lines = []
file_name = "path_to_file"
with open(file_name) as _file:
lines = _file.readlines()
new_lines = [line for line in lines if regex.search(line.strip())]
with open(file_name, "w") as _file:
_file.writelines(new_lines)