// Cosine Similarity
//
// cosine_similarity - cos_sim
//
// Sign of the product: +1 if positive, -1 if negative, 0 if zero
//
// Inputs:    2
// Outputs:   1 (similarity)
// Constants: 0

#include <math.h>
#include "ts.h"


ts_parameter_t const ts_cosine_similarity_p = { .n_inputs = 2, .n_outputs = 1, .n_constants = 0, .params_size = 0 };

uint_t ts_cosine_similarity_offset( ts_constant_t const *c )
{
	( void )c;
	return ( 0 );
}

int ts_cosine_similarity(
	fp_t * const *y, uint_t y_n,
	fp_t const * const *x, uint_t x_n,
	uint_t n, ts_constant_t const *c
)
{
	TS_PROLOGUE( ts_cosine_similarity_p );
	(void)c;
	for( uint_t i = 0; i < n; ++i )
	{
		fp_t p = x[0][i] * x[1][i];
		y[0][i] = p > 0.0 ? 1.0 : ( p < 0.0 ? -1.0 : 0.0 );
	}
	return 0;
}