Hi all and Merry Christmas!
I have a text entry widget and a save as button to save the contents of the text box to a .txt file. But when run, nothing is being saved. Can anyone tell me what I've missed...?
def file_saveAs():
from tkFileDialog import asksaveasfilename
contents = inputText.get(1.0, "end-1c")
save_file = asksaveasfilename(defaultextension = ".txt", initialdir = r"\\some\file\path\here")
line = []
for line in contents:
line = line.strip()
with open(save_file, "w") as outputFile:
outputFile.write(line)
It appears to me that it's the 'for line in contents' line where the problem lies. If I change the bottom line to 'output.write(contents)', then it saves the contents correctly, but I need to filter the contents based on a couple of other factors, so need the 'for line in' part.
Many thanks,
Chris.
change the for statement to:
for line in contents.split("\n"):
You need to split the contents into a list of lines before iterating over them.
You also need to move the with open ... statement outside the loop:
with open(save_file, "w") as outputfile:
for line in contents.split("\n"):
outputfile.write(line+"\n")
Related
I'm reading a text file which has instructions on each line. I want to assign the text on each line to it's own variable. When I do this, the value returned is nil but when I output the value of readlines[n] it is correct.
e.g.
# Using the variable (incorrect result)
puts current_zone_size
>
e.g.
# Using readlines after variable assignment (incorrect result)
current_zone_size = instructions.readlines[0]
instructions.readlines[0]
>
e.g.
# Using readlines (correct result)
instructions.readlines[0]
> 8 10
This is my code:
instructions = File.open("operator-input.txt", "r")
current_zone_size = instructions.readlines[0]
rover_init_location_orientation = instructions.readlines[1]
rover_movements = instructions.readlines[2]
This is the text in the file being read:
8 10
1 2 E
MMLMRMMRRMML
Edit:
Is the file being closed? Is this the reason I can't assign values from File.readlines[n] to variables if I'm not doing the variable assignment from within a block?
Also, the file will only ever have three lines which is why I'm not using a loop to read the lines.
IO#readlines reads all the lines in the file. It should not come as a surprise that, in order to read all the lines in the file, it has to read the entire file.
So, where is the file pointer after you read the entire file? It is at the end of the file.
What happens if you call IO#readlines the second time, when the file pointer is still at the end of the file? It will start reading at the position of the file pointer, which means it will read an empty file.
Therefore, if you want to do it the way you are doing it, you need to reset the file pointer to the beginning of the file every time you call IO#readlines:
instructions = File.open('operator-input.txt', 'r')
current_zone_size = instructions.readlines[0]
instructions.pos = 0
rover_init_location_orientation = instructions.readlines[1]
instructions.pos = 0
rover_movements = instructions.readlines[2]
Note also that you are leaking resources: you never close the file, so it will only by closed at the earliest by Ruby when the instructions variable gets out of scope and the File instance gets garbage-collected, and at the latest by the OS automatically when your Ruby process exits, which may be a long time later. So, your code should rather be:
instructions = File.open('operator-input.txt', 'r')
current_zone_size = instructions.readlines[0]
instructions.pos = 0
rover_init_location_orientation = instructions.readlines[1]
instructions.pos = 0
rover_movements = instructions.readlines[2]
instructions.close
In general, it is much better to use the block form of File::open, which closes the file handle automatically for you at the end of the block, and also ensures that this happens even in the case of complex control flow, errors, or exceptions:
File.open('operator-input.txt', 'r') do |instructions|
current_zone_size = instructions.readlines[0]
instructions.pos = 0
rover_init_location_orientation = instructions.readlines[1]
instructions.pos = 0
rover_movements = instructions.readlines[2]
end
Note, however, that what you want to do is horribly inefficient: you read the entire file, then take the first line, throw the rest away. Then you read the entire file again, take the second line, throw the rest away. Then you read the entire file again, take the third line, throw the rest away.
It makes much more sense to read the entire file once and then take the lines you need. Something like this:
File.open('operator-input.txt', 'r') do |instructions|
current_zone_size, rover_init_location_orientation, rover_movements =
instructions.readlines
end
However, in the case where all you do is open the file, read all lines, then immediately close it again, you should rather use the IO::readlines method instead of IO#readlines, since it does all three things for you in one call:
current_zone_size, rover_init_location_orientation, rover_movements =
File.readlines('operator-input.txt')
I ended up reading all the lines at once, now I'm able to set each variable outside of a block. Like this:
instructions = File.readlines "operator-input.txt"
current_zone_size = instructions[0]
rover_init_location_orientation = instructions[1]
rover_movements = instructions[2]
e.g.
puts current_zone_size
> 8 10
As part of my larger program, I want to create a logfile with the current time & date as part of the title. I can create it as follows:
malwareLog = open(datetime.datetime.now().strftime("%Y%m%d - %H.%M " + pcName + " Malware scan log.txt"), "w+")
Now, my app is going to call a number of other functions, so I'll need to open the file, write some output to it and close the file, several times. It doesn't seem to work if I simply go:
malwareLog.open(malwareLog, "a+")
or similar. So how should I open a dynamically created txt file that I don't know the actual filename for...?
When you create malwareLog object, it has name attribute which contains the file name.
Here's an example: (my test is your malwareLog)
import random
test = open(str(random.randint(0,999999))+".txt", "w+")
test.write("hello ")
test.close()
test = open(test.name, "a+")
test.write("world!")
test.close()
with open(test.name, "r") as f: print(f.read())
You also can store the file name in a variable before or after creating the file.
###Before
file_name = "123"
malwareLog = open(file_name, "w")
###After
malwareLog = open(random.randint(0,999999), "w")
file_name = malwareLog.name
I am a newbie programmer in python and I am trying to read multiple csv files from a folder, replace the delimiter for all the csv files with 'tab' delimiter and then output these files into a new folder with replaced delimiter. So far I am stuck at the beginning.
Here is the code that I started using, this is working for a single file. But am not able to work with multiple files in same folder.
print("\nWrite same CSV File with different string(Replace ',' with tab delimiter)")
with open('Names.csv','r') as csv_file:
csv_reader = csv.reader(csv_file)
with open('Names_new.csv', 'w') as new_file:
csv_writer = csv.writer(new_file, delimiter = '\t', lineterminator='\r')
for line in csv_reader:
csv_writer.writerow(line)
Please can someone point out some tips?
Thank you in advance!
I don't think the code in your question does what you want. However, here's how to embed it in more code that will read the csv files from a specified folder for processing.
listdir takes input_folder and yields a list of all of the files in that folder.
I loop through that list and process only those files whose names end with '.csv'.
from os import listdir
import csv
input_folder = 'catalyst/'
for file_name in listdir(input_folder):
if file_name.endswith('.csv'):
print ('---> processing input file: ', file_name)
with open(input_folder + file_name,'r') as csv_file:
csv_reader = csv.reader(csv_file)
out_file_name = file_name[:-3]+'_new.csv'
print (' creating', out_file_name )
with open(input_folder + out_file_name, 'w') as new_file:
csv_writer = csv.writer(new_file, delimiter = '\t', lineterminator='\r')
for line in csv_reader:
csv_writer.writerow(line)
I have two questions regarding the following code:
import subprocess
macSource1 = (r"\\Server\path\name\here\dhcp-dump.txt")
macSource2 = (r"\\Server\path\name\here\dhcp-dump-ops.txt")
with open (r"specific-pcs.txt") as file:
line = []
for line in file:
pcName = line.strip().upper()
with open (macSource1) as source1, open (macSource2) as source2:
items = []
for items in source1:
if pcName in items:
items_split = items.rstrip("\n").split('\t')
ip = items_split[0]
mac = items_split[4]
mac2 = ':'.join(s.encode('hex') for s in mac.decode('hex')).lower() # Puts the :'s between the pairs.
print mac2
print pcName
print ip
Firstly, as you can see, the script is searching for the contents of "specific-pcs.txt" against the contents of macSource1 to get various details. How do I get it to search against BOTH macSource1 & 2 (as the details could be in either file)??
And secondly, I need to have a stricter matching process as at the moment a machine called 'itroom02' will not only find it's own details, but also provide the details for another machine called '2nd-itroom02'. How would I get that?
Many thanks for your assistance in advance!
Chris.
Perhaps you should restructure it a bit more like this:
macSources = [ r"\\Server\path\name\here\dhcp-dump.txt",
r"\\Server\path\name\here\dhcp-dump-ops.txt" ]
with open (r"specific-pcs.txt") as file:
for line in file:
# ....
for target in macSources:
with open (target) as source:
for items in source:
# ....
There's no need to do e.g. line = [] immediately before you do for line in ...:.
As far as the "stricter matching" goes, since you don't give examples of the format of your files, I can only guess - but you might want to try something like if items_split[1] == pcName: after you've done the split, instead of the if pcName in items: before you split (assuming the name is in the second column - adjust accordingly if not).
I have downloaded a set of html files and saved the file paths which I saved them to in a .txt file. It has each path on a new line. I wanted to look at the first file in the list and then itterate through the whole list, opening the files and extracting data before going on to the next file.
My code works fine with a single path put in directly (for the first file) as:
path = r'C:\path\to\file.html'
and works if I itterate through the text file using:
file_list_fp = r'C:\path\to\file_with_pathlist.txt'
with open(file_list_fp, 'r') as file_list:
for filepath in file_list:
pathend = filepath.find('\n')
path = file[:pathend]
q = open(path, 'r').read()
but it fails when I try getting a single path using either:
with open(file_list_fp, 'r') as file_list:
path_n = file_list.readline()
end = path_n.find('\n')
path_bad1 = path_n[:end]
or:
with open(file_list_fp, 'r') as file_list:
path_bad2 = file_list.readline().split('\n')[0]
With these two my code exits just after that point. I can't figure out why. Any pointers very welcome. (I'm using Python 3.3.1 on windows.)