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

struct meas meas[2];
float lin_a, lin_b, target_off;
int target_dac;

main(argc, argv)
	char **argv;
{
	if (argc < 2 || argc > 3) {
		fprintf(stderr, "usage: %s meas-file [target]\n", argv[0]);
		exit(1);
	}
	read_meas_file(argv[1], meas, 2);
	if (argc > 2)
		target_off = atof(argv[2]);
	else
		target_off = 0;
	lin_a = (float)(meas[1].freq_offset - meas[0].freq_offset) /
		(float)(meas[1].dac_value - meas[0].dac_value);
	lin_b = (float)meas[1].freq_offset - lin_a * meas[1].dac_value;
	target_dac = (target_off - lin_b) / lin_a;
	printf("%d\n", target_dac);
	exit(0);
}