//
// t2f -- Convert time to frequency.
//
// - Input is a file of progressive time difference (phase) readings.
// - User gives sample period, in order to compute relative frequency error.
// - User gives nominal frequency, in order to compute absolute frequency.
// - Output is frequency series (absolute frequency).
//
// 16-Mar-2010 Tom Van Baak (tvb) www.LeapSecond.com/tools
//

#include <stdio.h>
#include <stdlib.h>

void main (int argc, char *argv[])
{
    char line[1000];
    long n;
    double f0, tau0;

    if (argc < 3) {
        fprintf(stderr, "Usage: %s [f0] [tau0]\n", argv[0]);
        exit(0);
    }

    f0 = atof(argv[1]);
    tau0 = atof(argv[2]);
    fprintf(stderr, "** f0 %lg\n", f0);
    fprintf(stderr, "** tau0 %lg\n", tau0);

    for (n = 0; fgets(line, sizeof line, stdin) != NULL; n += 1) {
        double t0, ti = atof(line);
        if (n > 0) {
            double fe = (ti - t0) / tau0;
            double f = f0 * (1.0 + fe);
            printf("%.15le\n", f);
        }
        t0 = ti;
    }
}