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reading a csv file

25 New Member
i have to do the following in c:
i want to read data from a csv file.
i need to read the first, second and fifth column of the file.
i am using fread but i cant get it to read the desired data.
Sep 19 '06 #1
13 12347
61 New Member
Give the detailed information.
You are working in windows or linux??
And the fields are separated by blanks or tabs???
Sep 19 '06 #2
georges the man
25 New Member
i am working in linux.

the data in the file are as the following:

name of the data, "day/month/year",values,va lues,values...
name of the data,"day/month/year",values,va lues,values...

and so on...
a comma is used for seperation
Sep 19 '06 #3
61 New Member
You can solve this problem in two ways......

Use the following command......

Spoonfeeding code removed, please read posting guidelines

Now read line by line from file2 and parse the fields.

Secondly you can do like this.....

Spoonfeeding code removed, please read posting guidelines

Now read all the three files at a time and get each word from each file and that will give you each field of a record.
Sep 19 '06 #4
georges the man
25 New Member
sorry i didnt understand the code...
i am using c language...
so if u can plz send back
Sep 19 '06 #5
61 New Member
Use the system() API to execute the above commands and then see the files file1, file2, file3. and then proceed.
Sep 19 '06 #6
georges the man
25 New Member
still dont get what u saying.

i need u to tell me how to do that in the
int main(void)

sorry for that
Sep 19 '06 #7
61 New Member
Try this one........

Spoonfeeding code removed - please read Posting Gudieliens

Now see the files file1, file2 and file3.
Sep 19 '06 #8
georges the man
25 New Member
what this mean??
system("cut -d',' f1 filename > file1");
system("cut -d',' f2 filename > file2");
system("cut -d',' f5 filename > file3");
Sep 19 '06 #9
61 New Member
See cut command will cut the required columns of the file and we are redirecting the output to a file. And system API will help you run any system command from the C code.

See the man page for cut.
Sep 19 '06 #10

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