base.h

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// This Source Code Form is subject to the terms of the Mozilla Public
// License, v. 2.0. If a copy of the MPL was not distributed with this
// file, You can obtain one at http://mozilla.org/MPL/2.0/.
#ifndef SP_BASE_H
#define SP_BASE_H
 
namespace sp
{
 
const double PI   = 3.14159265358979323846; 
const double PI_2 = 6.28318530717958647692;
 
arma_inline double sinc( double x )
{
    if( x == 0.0 )
        return 1.0;
    else
        return std::sin( PI * x ) / ( PI * x );
}
 
arma_inline arma::vec sinc( const arma::vec& x )
{
    arma::vec out;
    out.copy_size( x );
    for( unsigned int n = 0; n < out.size(); n++ )
    {
        out( n ) = sinc( x( n ) );
    }
    return out;
}
 
arma_inline double besseli0( double x )
{
    double y = 1.0, s = 1.0, x2 = x * x, n = 1.0;
    while( s > y * 1.0e-9 )
    {
        s *= x2 / 4.0 / ( n * n );
        y += s;
        n += 1;
    }
    return y;
}
 
template <typename T> double angle( const std::complex<T>& x )
{
    return std::arg( x );
}
 
arma_inline arma::vec angle( const arma::cx_vec& x )
{
    arma::vec P;
    P.copy_size( x );
    for( unsigned int r = 0; r < x.n_rows; r++ )
        P( r ) = std::arg( x( r ) );
    return P;
}
 
arma_inline arma::mat angle( const arma::cx_mat& x )
{
    arma::mat P;
    P.copy_size( x );
    for( unsigned int r = 0; r < x.n_rows; r++ )
        for( unsigned int c = 0; c < x.n_cols; c++ )
            P( r, c ) = std::arg( x( r, c ) );
    return P;
}
 
arma_inline arma::vec unwrap( const arma::vec& x )
{
    arma::vec    P;
    double       pacc = 0, pdiff = 0;
    const double thr = PI * 170 / 180;
    P.copy_size( x );
    P( 0 ) = x( 0 );
    for( unsigned int r = 1; r < x.n_rows; r++ )
    {
        pdiff = x( r ) - x( r - 1 );
        if( pdiff >= thr )
            pacc += -PI_2;
        if( pdiff <= -thr )
            pacc += PI_2;
        P( r ) = pacc + x( r );
    }
    return P;
}
 
 
 
arma_inline arma::vec timevec( const int N, const double Fs )
{
    return arma::regspace( 0, N - 1.0 ) / Fs;
}
 
template <typename T> arma::Col<T> fftshift( const arma::Col<T>& Pxx )
{
    arma::Col<T> x( Pxx.n_elem );
    x = shift( Pxx, floor( Pxx.n_elem / 2 ) );
    return x;
}
 
template <typename T> arma::Col<T> ifftshift( const arma::Col<T>& Pxx )
{
    arma::Col<T> x( Pxx.n_elem );
    x = shift( Pxx, -ceil( Pxx.n_elem / 2 ) );
    return x;
}
 
template <typename T> arma::Mat<T> fftshift( const arma::Mat<T>& Pxx )
{
    arma::uword  R = Pxx.n_rows;
    arma::uword  C = Pxx.n_cols;
    arma::Mat<T> x( R, C );
    x = arma::shift( Pxx, static_cast<arma::sword>( floor( R / 2 ) ), 0 );
    x = arma::shift( x, static_cast<arma::sword>( floor( C / 2 ) ), 1 );
    return x;
}
 
template <typename T> arma::Mat<T> ifftshift( const arma::Mat<T>& Pxx )
{
    arma::uword  R = Pxx.n_rows;
    arma::uword  C = Pxx.n_cols;
    arma::Mat<T> x( R, C );
    x = shift( Pxx, -ceil( R / 2 ), 0 );
    x = shift( x, -ceil( C / 2 ), 1 );
    return x;
}
 
 
 
arma_inline std::string sp_version( void )
{
    return std::to_string( SP_VERSION_MAJOR ) + "." + std::to_string( SP_VERSION_MINOR ) + "." + std::to_string( SP_VERSION_PATCH );
}
 
// err_handler("Error string")
//      Prints an error message, waits for input and
//      then exits with error
#define err_handler( msg )                                                                          \
    {                                                                                               \
        std::cout << "SigPack Error [" << __FILE__ << "@" << __LINE__ << "]: " << msg << std::endl; \
        std::cin.get();                                                                             \
        exit( EXIT_FAILURE );                                                                       \
    }
 
// wrn_handler("Warning string")
//      Prints an warning message
#define wrn_handler( msg )                                                                            \
    {                                                                                                 \
        std::cout << "SigPack warning [" << __FILE__ << "@" << __LINE__ << "]: " << msg << std::endl; \
    }
 
} // namespace sp
#endif