lib/prime_number_oscillator.c


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// Prime Number Oscillator
//
// prime_number_oscillator
//
// Prime Number Oscillator
//
// 
//
// Inputs:    1
// Outputs:   1
// Constants: 0


#include "ts.h"


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

uint_t ts_prime_number_oscillator_offset( ts_constant_t const *c )
{
	( void )c;
	return ( 23 );
}

int ts_prime_number_oscillator(
	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_prime_number_oscillator_p );
	(void)c;
    fp_t last_gap = 0;
    fp_t prev_prime = 0;
    bool first_prime = true;

    for( uint_t i = 0; i < n; ++i )
    {
        long v = (long)x[0][i];
        bool is_p = false;

        if( v >= 2 )
        {
            if( v == 2 )
                is_p = true;
            else if( v % 2 != 0 )
            {
                is_p = true;
                for( long d = 3; d <= v / d; d += 2 )
                {
                    if( v % d == 0 )
                    {
                        is_p = false;
                        break;
                    }
                }
            }
        }

        if( is_p )
        {
            if( first_prime )
            {
                prev_prime = (fp_t)v;
                first_prime = false;
                y[0][i] = 0;
            }
            else
            {
                last_gap = (fp_t)v - prev_prime;
                prev_prime = (fp_t)v;
                y[0][i] = last_gap;
            }
        }
        else
        {
            y[0][i] = last_gap;
        }
    }
	return 0;
}