void main(void)
{
hp1();
hp2();
hp3();
hp4();
}
/* Returns the normalized MI scores.
*
* Parameters
* dx (IN) : x-data sorted in increasing order by dx-values
* dy (IN) : y-data sorted in increasing order by dx-values
* n (IN) : number of elements in dx and dy
* Q_map (IN) : the map Q computed by EquipartitionYAxis() sorted in
* increasing order by dx-values
* q (IN) : number of partitions in Q_map
* P_map (IN) : the map P computed by GetSuperclumpsPartition() sorted
* in increasing order by Dx-values
* p (IN) : number of partitions in P_map
* x (IN) : maximum grid size on dx-values
* score (OUT) : mutual information scores. score must be a
* preallocated array of dimension x-1
* Returns
* 0 on success, 1 if an error occurs
*/
int OptimizeXAxis(double *dx, double *dy, int n, int *Q_map, int q,
int *P_map, int p, int x, double *score)
{
int i, s, t, l;
int *c;
int **cumhist;
double **I, **HP2Q;
double F, F_max, HQ, ct, cs;
/* return score=0 if p=1 */
if (p == 1)
{
for (i=0; i<x-1; i++)
score[i] = 0.0;
return 0;
}
/* compute c */
c = compute_c(P_map, p, n);
if (c == NULL)
goto error_c;
/* compute the cumulative histogram matrix along P_map */
cumhist = compute_cumhist(Q_map, q, P_map, p, n);
if (cumhist == NULL)
goto error_cumhist;
/* I matrix initialization */
I = init_I(p, x);
if (I == NULL)
goto error_I;
/* Precomputes the HP2Q matrix */
HP2Q = compute_HP2Q(cumhist, c, q, p);
if (HP2Q == NULL)
goto error_HP2Q;
/* compute H(Q) */
HQ = hq(cumhist, q, p, n);
/*
* Find the optimal partitions of size 2
* Algorithm 2 in SOM, lines 3-8
*/
for (t=2; t<=p; t++)
{
F_max = -DBL_MAX;
for (s=1; s<=t; s++)
{
F = hp3(c, s, t) - hp3q(cumhist, c, q, p, s, t);
if (F > F_max)
{
I[t][2] = HQ + F;
F_max = F;
}
}
}
/*
* Inductively build the rest of the table of
* optimal partitions
* Algorithm 2 in SOM, lines 10-17
*/
for (l=3; l<=x; l++)
{
for (t=l; t<=p; t++)
{
ct = (double) c[t-1];
F_max = -DBL_MAX;
for (s=l-1; s<=t; s++)
{
cs = (double) c[s-1];
F = ((cs/ct) * (I[s][l-1]-HQ))
- (((ct-cs)/ct) * HP2Q[s][t]);
if (F > F_max)
{
I[t][l] = HQ + F;
F_max = F;
}
}
}
}
/* Algorithm 2 in SOM, line 19 */
for (i=p+1; i<=x; i++)
I[p][i] = I[p][p];
/* score */
for (i=2; i<=x; i++)
score[i-2] = I[p][i] / MIN(log(i), log(q));
/* start frees */
for (i=0; i<=p; i++)
free(HP2Q[i]);
free(HP2Q);
for (i=0; i<=p; i++)
free(I[i]);
free(I);
for (i=0; i<q; i++)
free(cumhist[i]);
free(cumhist);
free (c);
/* end frees*/
return 0;
/* gotos*/
error_HP2Q:
for (i=0; i<=p; i++)
free(I[i]);
free(I);
error_I:
for (i=0; i<q; i++)
free(cumhist[i]);
free(cumhist);
error_cumhist:
free(c);
error_c:
return 1;
}
