Question

I would like to open multiple files with the file names changed little.

For example , I want to open

abc.001.xyz.010.trj

After some operation onto the data file I want to save the results into file:

out.abc.001.xyz.010.trj.dat

And this process should go on until 10 files.

I know how to open this file

readfile = abc.001.xyz.010.trj
f = open(readfile, "r")

later I tried to write into file

outfile = out.readfile
f = open(outfile, "w")

but I fail. Expect to get output file as

 out.abc.001.xyz.010.trj.dat

for every loop.

Thanks.

Answer 1

I know how to open this file

No, you don’t. Your initialization for the filename is invalid and would result in SyntaxError.

You should have written

readfile = "abc.001.xyz.010.trj"
f = open(readfile, "r")

And in similar way, to open the output file

outfile = "out."  + readfile
f = open(outfile, "w")

Btw, there are other issues, in your code which is not very conventional.

Generally People Tend to open files and close it and don’t rely on garbage collections, and even better, enclose the entire file operation inside a with construct