view xthresh.c @ 333:cc3f9d1ca2cd

Ugly hack upon ugly hack:

* extend adb__query() to take a bunch of other arguments that allow
  useful functionality through to the SOAP server;
* alter the RadiusQuery reporter so that the count for tracks is
  returned through SOAP, punning one of the result fields for the
  purpose;
* alter argv construction to be more dynamic, to reflect that the very
  presence of some arguments changes audioDB behaviour.

Now test 0020 passes, only some 12 months after it was originally
written, yay.  Alter test 0050 also, so that the results are actually
vaguely what would be expected from a radius search; they are not
completely checked for correctness, but are (apart from the last two)
the same as test 0040.

I believe that the modifications are backward compatible; lightly
testing with an old audioDB binary suggests that old-format SOAP queries
continue to work.  Currently too baby-encumbered to think of how to test
this fully.

#include <gsl/gsl_sf.h>
#include <stdio.h>
#include <stdlib.h>
#include <math.h>

int main(int argc, char *argv[]) {
  if(argc != 4) {
    fprintf(stderr, "Wrong number of arguments: %d\n", argc);
    exit(1);
  }

  long int meanN = strtol(argv[1], NULL, 10);

  double d = strtod(argv[2], NULL);
  double sigma2 = strtod(argv[3], NULL);

  double logw = (2 / d) * gsl_sf_log(-gsl_sf_log(0.99));
  double logxthresh = gsl_sf_log(sigma2) + logw
    - (2 / d) * gsl_sf_log(meanN)
    - gsl_sf_log(d/2)
    - (2 / d) * gsl_sf_log(2 / d)
    + (2 / d) * gsl_sf_lngamma(d / 2);

  printf("w: %f\n", exp(logw));
  printf("x_thresh: %f\n", exp(logxthresh));
  exit(0);
}