#!/usr/bin/perl -w


@todo= `ls *.dat`;

$count=0;
foreach(@todo){
chomp;
$this=$_;
open TMP, ">fit_tmp";
print TMP "f1(x) = c*(-a + cos(3.14159*2*j*x))*exp(-2*x*r) \n"; #defines the fitting function for the NH J-modulated data.
print TMP "c=1;  a=0.01; r=20; j=90;\n"; #may need to changed for proper initialization for curve fitting.
print TMP "fit f1(x) \'$this\' using 1:2 via c,a,r,j\n"; #fits the data according to the equation f1(x) with the variable parameters c, a, j, and r.
close TMP;
system ("rm","-f","fit.log");
system ("gnuplot","fit_tmp");
$count++;

$c=0;$delta_c=0; #c is the initial intensity of the peak
$a=0;$delta_a=0; #a accounts for imperfection of pi pulses during the experiment (usually 0 < a < 0.05)
$j=0;$delta_j=0; #j is the one-bond N-H j-coupling value in Hz
$r=0;$delta_r=0; #r is the R2 relaxation rate in sec

open DATA,"fit.log";
while (<DATA>){
	if  (/Final set of parameters\s*Asymptotic Standard Error/){
		while (<DATA>){
                        @_ = split;
                        if ( defined $_[0] && $_[0] eq 'c'){
                                $c = $_[2];
                                $delta_c = $_[4];
                        }
                        elsif ( defined $_[0] && $_[0] eq 'a'){
                                $a = $_[2];
                                $delta_a = $_[4];
                        }
                        elsif ( defined $_[0] && $_[0] eq 'j'){
                                $j = $_[2];
                                $delta_j = $_[4];
                        }
                        elsif ( defined $_[0] && $_[0] eq 'r'){
                                $r = $_[2];
                                $delta_r = $_[4];
                        }
                        last if ($c !=0 && $a !=0 && $j !=0 && $r !=0);
		}
	}
}

open TMP2,">plot_tmp";
print TMP2 "plot [0:0.015] \'$this\',$c*(-$a + cos(3.14159*2*$j*x))*exp(-2*x*$r) title 'c = $c +- $delta_c     a = $a +- $delta_a     j = $j +- $delta_j     r = $r +- $delta_r'";

print TMP2 "\npause -1";

system ("gnuplot","plot_tmp");
}