static void gaussian_kernel(ntuple_list kernel, float sigma, float mean)
{
float sum = 0.0;
//float val;
unsigned int i;
/* check parameters */
// if( kernel == NULL || kernel->values == NULL )
// error("gaussian_kernel: invalid n-tuple 'kernel'.");
// if( sigma <= 0.0 ) error("gaussian_kernel: 'sigma' must be positive.");
/* compute Gaussian kernel */
if( kernel->max_size < 1 ) enlarge_ntuple_list(kernel);
kernel->size = 1;
for(i=0;i<kernel->dim;i++)
{
// val = ( (float) i - mean ) / sigma;
// kernel->values[i] = exp( -0.5 * val * val );
kernel->values[i] = exp( -0.5 * (( (float) i - mean ) / sigma) * (( (float) i - mean ) / sigma) );
sum += kernel->values[i];
}
/* normalization */
if( sum >= 0.0 ) for(i=0;i<kernel->dim;i++) kernel->values[i] /= sum;
}
/** Add a 1-tuple to an 1-tuple list.
*/
static void add_1tuple( ntuple_list out, double v1)
{
/* check parameters */
if( out == NULL ) error("add_1tuple: invalid n-tuple input.");
if( out->dim != 1 ) error("add_1tuple: the n-tuple must be a 1-tuple.");
/* if needed, alloc more tuples to 'out' */
if( out->size == out->max_size ) enlarge_ntuple_list(out);
if( out->values == NULL ) error("add_2tuple: invalid n-tuple input.");
/* add new 2-tuple */
out->values[ out->size * out->dim] = v1;
/* update number of tuples counter */
out->size++;
}
/** Copy ntuple_list
*/
static void copy_ntuple(ntuple_list src, ntuple_list des)
{
/* check parameters */
if( src == NULL ) error("copy_ntuple: invalid n-tuple input.");
if( des == NULL ) error("copy_ntuple: invalid n-tuple input.");
if( src->dim != des->dim ) error("copy_ntuple: different dimension of input.");
int i, j, nb, dim;
nb = src->size;
dim = src->dim;
des->size = 0;
for(i = 0; i < nb; i++) {
if(des->size == des->max_size)
enlarge_ntuple_list(des);
for(j = 0; j < dim; j++)
des->values[i*dim+j] = src->values[i*dim+j];
des->size++;
}
}
