Programming :: Using Python To Merge Two Text Files Line For Line
Jul 6, 2010
I'm a bit new to Python programming and hoped that someone might be able to help with a problem I'm having. What I essentially want to do is to combine two text files line for line. I know how to do this in a bash script so to give you a better idea here's the code for that:
Code:
This is basically for adding on values to the end of a CSV file that uses ';' as the delimiter. So say file1 said:
And file2 said:
Then running this command would create merged_file1_and_file2 which would be:
The code I'm using at the moment is:
Code:
As I'm sure any experienced python programmer will see, this prints out the first line of the file "csvraw" and then all of the lines of "stamps" and then the remainder of "csvraw".
What I'd like to do is something like: (pseudo code, I know it's not python ;-))
Code:
Is this possible? I've tried googling and my Python Pocket Reference hasn't been much help. I've looked at pickling but that doesn't seem appropriate.
I have two txt files containing x and y coordinates: xcoord.txt & ycoord.txt. I need to open them; read them line by line to get each coordinate; then each time I need to update Xs and Ys parameters inside another file called "dc.in" with the grabbed values.
Finally each time I need to run two exe files ( dc_2002 and st_vac) and produce corresponding output for each Xs and Ys ( dc.in is an input file for this exe files)
I have written the following code but it does not work:
I am trying to write a program in C which compares two files and prints the line that is equal.
Here file1.txt has
and file2.txt has
Note: file2.txt consist of only a single string where as file2.txt has multiple lines. Actually im comparing two files with md5sum values.
Here is the code but it compares only first line of files..but it should compare the whole file1..and sorry iam a beginner in C can any1 sujest some modification to this code so that..it can compare file2 with entire file1
Was wondering if any perl guru's could help me with a quick log file adjustment. I have a text file that looks like so (tabs and newlines are revealed so you can see what separates the data):
There are maybe 100 lines of text in this file at any given time. I need to delete all duplicate lines only looking at the first bit of text prior to the first tab. It doesn't matter which one gets deleted as long as there are no two lines that begin with that same text at the beginning before the first tab. So in this example, either the fist line "1234" or the last line "1234" would need to be deleted. I already have code in my script that opens the files - I just need the code to read the text into an array and the part that would find matches based on the above criteria, and make the deletions.
If it would be easier, I can even do a system call and use SED (v4.1.5) and/or AWK (3.1.5) instead.
bash 3.1.17(2) I'm trying do write a shell script which must operate on each line of an ASCII text file. So, all the code must be inside a loop, and inside the loop, the first thing should be to read the next line from the file. I have the bash read command. But it reads from stdin. Any way to make read from a file?
I'm trying to add text to a file for a specific group of users, I'll need to do examples as I can't think of an easy way of explaining, my file is like this:
Code:
users{ user1 user2
[code]....
At the present my code lists all the available groups, how would I add a user to a specified group? (e.g add "members user3") to the end of group 1 for example. So the code ends up like this
I'm extracting data from a xml file writing it to separate files then combining the results as a csv file.The problem is keeping the separate files in sync line by line.When a grep does not action I would like to put in a blank line or something to keep the lines in order.When the "<title>" is missing as in as in the first"<programme </programme>" that's where I need somethingto write to the file as dummy data to increment the line
I have two files, file1.traj and file2.traj. Both these files contain identical data and the data are arranged in same format in them. The first line of both files is a comment.
At line 7843 of both files there is a cartesian coordinate X, Y and Z ( three digits ). And at line 15685 there is another three digits. The number of lines in between two cartesian coordinates are 7841. And there are few hundreds of thousands of lines in a file.
What I need to do is copy the X Y Z coordinate (three digits) from file1.traj at line 7843 and paste into file2.traj at the same line number as in file1.traj. The next line will be 15685 from file1.traj and replace at line 15685 at file2.traj. And I dont want other lines (data) in file2.traj get altered. This sequence shall be going on until the end of the file. Means copy and substitude the selected lines from file1.traj into file2.traj.
I tried to use paste command but I cant do for specified line alone.
Here i showed the data format in the file. I used the line number for clarity purpose.
15 this is a sentence containing various words and spaces 34 this is a another sentence containing various words and spaces
cat file2.txt
2 this is sentence1file2 6 this is sentence2file2 54 this is sentence3file2
I would like to join these 2 files. The result should look as follows :
cat joinedfile.txt
2 this is sentence1file2 6 this is sentence2file2 15 this is a sentence containing various words and spaces 34 this is a another sentence containing various words and spaces 54 this is sentence3file2
==> so the joined file must be sorted on the first number. Any ideas how this can be achieved ?
I want to access a file, and check the length of every line.After, i want to check and replace all lines with length over 10 characters, with a message.Does anyone have a clue on that?
I have to delete a certain line of text from the a textfile via ubuntu's shell scripting.I have done research, and it seems that most people advocate the usage of sed /d option. sed makes does not edit the text file. Hence, most options I discovered involved the use of a temporary variable/textfile and then overwriting the old file with the temporary new file. Is there anyway whereby I can bypass the use of temporary storage containers? I hope there is any magical combination of commands to edit the file directly.
How can I list the following with grep. I want to extract 2 lines fron a text file The fixed known part if it exists will static text and the text line after it will change.
A sample file . . textline1
[code]....
If the fixed part does Not exist how can I return error code 1
a sed command to add a text before line number in text file? I have text file with 500 lines, and i want to add 3 more lines with text after line 300, OR before line 302, isn't no problem.
My site was recently hacked and a line of <JAVASCRIPT> was inserted into all my php files. Is there a way to pull just that one line out of all the php files on the server? I was thinking of using a grep -iR <CODE> *.php then piping thru sed
Say I have a text file like: Code: 1 3 4 How would I use ksh to put the number '2' into the second line of that file?Okay it's not bash, it's ksh because this computer is OpenBSD
I have a text file called namelist.wps. In this file there is a line that reads:
Code: start_date = '2010-12-26_12:00:00', '2010-12-26_12:00:00', I have to automatically update the year, month, and day of month for this line without changing the rest of the file. Here is the script that I have:
I have huge text files with two fields, the first is a string the second is an integer. The files are sorted by the first field. What I'd like to get in the output is one line per unique string and the sum of the numbers for the identical strings. Some strings appear only once while other appear multiple times. Given the sample data below, for the string glehnia I'd like to get 10+22=32 in the result. how to do this either with gnuwin32 command line tools or in linux shell?
How can I replace one instance of a word in a text file with a piece of text that spreads several lines ? I know sed or awk is the way to go but don't know that how I can introduce new paragraphs using these tools
I simply want to read a file "data.txt" line by line Then char by char and add them into a result var. The file is supossed to always contain numeric values
I have a text file called namelist.wps. In this file there is a line that reads:Code: start_date = '2010-12-26_12:00:00', '2010-12-26_12:00:00', I have to automatically update the year, month, and day of month. I set values for the year, month, and day of month using the following code in a c-shell script:Code: set y1 = `date +%Y`set m1 = `date +%m`set d1 = `date +%d` After I do this, how do I update year, month, and day of month, without changing any of the other lines in the namelist.wps file?
I want to get the last term of an unknown-sized text line, by usig the awk command. Is there any variable which points to the last term of a text line ? (obviously, y can obtain that term if i knew how many terms does the line have... i.e. awk '{print $12}' ; if we are talking about a 12-terms text line) I wonder if there is an option like $?, to get the last term.
I am thinking of appending something to each line in a text file with Java. I prefer not write a new file with content appended from the old one.That 'something' would probably be Time Stamp when the file is created (which is same for each line).I am not sure Java provide some easy way for it or not
I would like to insert prior to the word "three" all items from this second file with the following contents:
Code:
four three two one
Now my issue is, and I have been using both sed and awk currently, that after the second line of the new file is read there will of course now be 2 copies of the word "three" but I would like to only insert the final 2 words, ie "two" and "one" prior to only the first occurrence of the word "three" so final file will look like:
Code:
one two four
[code]....
So here there is now only one of each word from the second file joined to make the new file. For simple code I have tried something like the following:
Code:
while read line do awk -v n=$line '!f && /three/{print n;f++}1' file1 > tmp_file mv tmp_file file1 done < file2
Now this works but seems very clumsy to me. There is obviously a better sed and / or awk out there.
