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/*
FILE...: test_phi0.c
AUTHOR.: Matthew C. Valenti, Rohit Iyer Seshadri, David Rowe, Don Reid
CREATED: Sep 2018
Compare new generated phi0 function to what was originally in mpdecode_core.c
*/
#include <math.h>
#include <stdlib.h>
#include <stdio.h>
#include "phi0.h"
/* Original Phi function */
static float phi0_orig( float x ) {
float z;
if (x>10)
return( 0 );
else if (x< 9.08e-5 )
return( 10 );
else if (x > 9)
return( 1.6881e-4 );
/* return( 1.4970e-004 ); */
else if (x > 8)
return( 4.5887e-4 );
/* return( 4.0694e-004 ); */
else if (x > 7)
return( 1.2473e-3 );
/* return( 1.1062e-003 ); */
else if (x > 6)
return( 3.3906e-3 );
/* return( 3.0069e-003 ); */
else if (x > 5)
return( 9.2168e-3 );
/* return( 8.1736e-003 ); */
else {
z = (float) exp(x);
return( (float) log( (z+1)/(z-1) ) );
}
}
////////////////////////////////////////////////////
// Main
int main(void) {
float xf;
float error;
int errsum = 0;
int errsum2 = 0;
int errcnt = 0;
for (xf=10.5f; xf>5e-5f; xf = xf * 0.9) {
float orig = phi0_orig(xf);
float new = phi0(xf);
error = new - orig;
printf("%10.4f: %10.6f - %10.6f = %10.6f", xf, new, orig, error);
if ((error >= 0.001) && (error >= (orig * 0.1))) printf(" ****");
printf("\n");
errsum += error;
errsum2 += error * error;
errcnt ++;
}
printf("Net error %f\n", (double)errsum);
printf("avg error %f\n", (double)errsum/errcnt);
printf("rms error %f\n", (double)sqrt(errsum2/errcnt));
return(0);
}
/* vi:set ts=4 et sts=4: */
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