Thread: File I/O Manipulation

Hi,

I am writing data to *.dat file in columns. How can I manipulate the output so every number in the first column is 6 characters wide and the second column is 5 characters wide? In C++, I used setw(6) to set the width of each output. How can I do this in C?

This didn't work.

Code:

fprintf(outfile, "%03.2lf %2.2lf", data1[i], data2[i]);

I try to use strncpy to acquire the second column's data. Since the first column has different widths, based on the number, I index at the wrong position.

Basically I need to read ascii data into the program.

Thanks!

Change the %3 to a %6, and the %2 to %5, that's your width of field settings. I have never seen an "lf" data designation for printf. Try just "f'.

This seems to work when I output double's

Code:

	fprintf(OutTable, "%8.3lf%8.2lf\n",ChtTimes[k],ChtValues[k]);

and this does not

Code:

	fprintf(OutTable, "%7.3lf%8.2lf\n",ChtTimes[k],ChtValues[k]);

Does the width need to be 8 for outputing a double?