PV-WAVE Foundation > Tutorial > Printing and Exporting Data > Lesson 1: Transferring Data with WRITEU
Lesson 1: Transferring Data with WRITEU
In this lesson, you will create a PV-WAVE program that creates a binary data file containing a 4-by-4 array of floating-point values, and then create a C program that reads and displays that binary data file.
To use PV-WAVE to create a binary data file, do the following:
1. Open a file for output.
OPENW, 1, 'float.dat'
2. Write a 4-by-4 array with each element set equal to its one-dimensional index.
WRITEU, 1, FINDGEN(4, 4)
3. Close the file.
CLOSE, 1
You are now ready to write the C program that reads this binary file.
To create the C program to read and display float.dat, do the following:
1. Write or copy the following C program.
#include <stdio.h>
main()
{
float data[4][4];
FILE *infile;
int i, j;
infile = fopen("float.dat", "r");
(void) fread(data, sizeof(data), 1, infile);
(void) fclose(infile);
for (i=0; i < 4; i++)
{
    for (j=0; j < 4; j++)
    printf("%8.1f", data[i][j]);
    printf("\n");
    }
}
2. Run this program. Your output should look similar to the following:
    0.0     1.0    2.0    3.0    
    4.0     5.0     6.0    7.0    
    8.0    9.0    10.0    11.0   
   12.0   13.0    14.0    15.0