Example #1
0
def A_matrix():
    '''

    Calculates A matrix whose elements :math:`A_{p i}` are given by
    :math:`A_{pi} = \\int^1_{-1} L_p(\\xi)L_i(\\xi) \\frac{dx}{d\\xi}`

    The integrals are computed using the integrate() function.
    Since elements are taken to be of equal size, :math:`\\frac {dx}{d\\xi}`
    is same everywhere
    
    Returns
    -------

    A_matrix : arrayfire.Array [N_LGL N_LGL 1 1]
               The value of integral of product of lagrange basis functions
               obtained by LGL points, using the integrate() function

    '''
    # Coefficients of Lagrange basis polynomials.
    lagrange_coeffs = params.lagrange_coeffs
    lagrange_coeffs = af.reorder(lagrange_coeffs, 1, 2, 0)

    # Coefficients of product of Lagrange basis polynomials.
    lag_prod_coeffs = af.convolve1(lagrange_coeffs,\
                                   af.reorder(lagrange_coeffs, 0, 2, 1),\
                                   conv_mode=af.CONV_MODE.EXPAND)
    lag_prod_coeffs = af.reorder(lag_prod_coeffs, 1, 2, 0)
    lag_prod_coeffs = af.moddims(lag_prod_coeffs, params.N_LGL**2,
                                 2 * params.N_LGL - 1)

    dx_dxi = params.dx_dxi
    A_matrix = dx_dxi * af.moddims(lagrange.integrate(lag_prod_coeffs),\
                                             params.N_LGL, params.N_LGL)

    return A_matrix
Example #2
0
def lagrange_polynomial_coeffs(x):
    '''
    This function doesn't use poly1d. It calculates the coefficients of the
    Lagrange basis polynomials.




    A function to get the analytical form and the coefficients of
    Lagrange basis polynomials evaluated using x nodes.

    It calculates the Lagrange basis polynomials using the formula:

    .. math:: \\
        L_i = \\prod_{m = 0, m \\notin i}^{N - 1}\\frac{(x - x_m)}{(x_i - x_m)}

    Parameters
    ----------

    x : numpy.array [N_LGL 1 1 1]
        Contains the :math: `x` nodes using which the
        lagrange basis functions need to be evaluated.

    Returns
    -------

    lagrange_basis_coeffs : numpy.ndarray
                            A :math: `N \\times N` matrix containing the
                            coefficients of the Lagrange basis polynomials such
                            that :math:`i^{th}` lagrange polynomial will be the
                            :math:`i^{th}` row of the matrix.

    '''
    X = np.array(x)
    lagrange_basis_poly = []
    lagrange_basis_coeffs = af.np_to_af_array(
        np.zeros([X.shape[0], X.shape[0]]))

    for j in np.arange(X.shape[0]):
        lagrange_basis_k = af.np_to_af_array(np.array([1.]))

        for m in np.arange(X.shape[0]):
            if m != j:
                lagrange_basis_k = af.convolve1(lagrange_basis_k,\
                        af.np_to_af_array(np.array([1, -X[m]])/ (X[j] - X[m])),\
                                                   conv_mode=af.CONV_MODE.EXPAND)
        lagrange_basis_coeffs[j] = af.transpose(lagrange_basis_k)

    return lagrange_basis_coeffs
Example #3
0
def poly1d_product(poly_a, poly_b):
    '''
    Finds the product of two polynomials using the arrayfire convolve1
    function.

    Parameters
    ----------
    poly_a : af.Array[N degree_a 1 1]
             :math:`N` polynomials of degree :math:`degree`
    poly_b : af.Array[N degree_b 1 1]
             :math:`N` polynomials of degree :math:`degree_b`
    '''
    return af.transpose(
        af.convolve1(af.transpose(poly_a),
                     af.transpose(poly_b),
                     conv_mode=af.CONV_MODE.EXPAND))
af.display(af.fft2(a))
af.display(af.dft(a))
af.display(af.real(af.ifft2(af.fft2(a))))
af.display(af.real(af.idft(af.dft(a))))

a = af.randu(4, 4, 2)
af.display(a)

af.display(af.fft3(a))
af.display(af.dft(a))
af.display(af.real(af.ifft3(af.fft3(a))))
af.display(af.real(af.idft(af.dft(a))))

a = af.randu(10, 1)
b = af.randu(3, 1)
af.display(af.convolve1(a, b))
af.display(af.fft_convolve1(a, b))
af.display(af.convolve(a, b))
af.display(af.fft_convolve(a, b))

a = af.randu(5, 5)
b = af.randu(3, 3)
af.display(af.convolve2(a, b))
af.display(af.fft_convolve2(a, b))
af.display(af.convolve(a, b))
af.display(af.fft_convolve(a, b))

a = af.randu(5, 5, 3)
b = af.randu(3, 3, 2)
af.display(af.convolve3(a, b))
af.display(af.fft_convolve3(a, b))
Example #5
0
def simple_signal(verbose=False):
    display_func = _util.display_func(verbose)
    print_func   = _util.print_func(verbose)

    a = af.randu(10, 1)
    pos0 = af.randu(10) * 10
    display_func(af.approx1(a, pos0))

    a = af.randu(3, 3)
    pos0 = af.randu(3, 3) * 10
    pos1 = af.randu(3, 3) * 10

    display_func(af.approx2(a, pos0, pos1))

    a = af.randu(8, 1)
    display_func(a)

    display_func(af.fft(a))
    display_func(af.dft(a))
    display_func(af.real(af.ifft(af.fft(a))))
    display_func(af.real(af.idft(af.dft(a))))

    a = af.randu(4, 4)
    display_func(a)

    display_func(af.fft2(a))
    display_func(af.dft(a))
    display_func(af.real(af.ifft2(af.fft2(a))))
    display_func(af.real(af.idft(af.dft(a))))

    a = af.randu(4, 4, 2)
    display_func(a)

    display_func(af.fft3(a))
    display_func(af.dft(a))
    display_func(af.real(af.ifft3(af.fft3(a))))
    display_func(af.real(af.idft(af.dft(a))))

    a = af.randu(10, 1)
    b = af.randu(3, 1)
    display_func(af.convolve1(a, b))
    display_func(af.fft_convolve1(a, b))
    display_func(af.convolve(a, b))
    display_func(af.fft_convolve(a, b))

    a = af.randu(5, 5)
    b = af.randu(3, 3)
    display_func(af.convolve2(a, b))
    display_func(af.fft_convolve2(a, b))
    display_func(af.convolve(a, b))
    display_func(af.fft_convolve(a, b))

    a = af.randu(5, 5, 3)
    b = af.randu(3, 3, 2)
    display_func(af.convolve3(a, b))
    display_func(af.fft_convolve3(a, b))
    display_func(af.convolve(a, b))
    display_func(af.fft_convolve(a, b))


    b = af.randu(3, 1)
    x = af.randu(10, 1)
    a = af.randu(2, 1)
    display_func(af.fir(b, x))
    display_func(af.iir(b, a, x))
Example #6
0
def simple_signal(verbose=False):
    display_func = _util.display_func(verbose)
    print_func = _util.print_func(verbose)

    a = af.randu(10, 1)
    pos0 = af.randu(10) * 10
    display_func(af.approx1(a, pos0))

    a = af.randu(3, 3)
    pos0 = af.randu(3, 3) * 10
    pos1 = af.randu(3, 3) * 10

    display_func(af.approx2(a, pos0, pos1))

    a = af.randu(8, 1)
    display_func(a)

    display_func(af.fft(a))
    display_func(af.dft(a))
    display_func(af.real(af.ifft(af.fft(a))))
    display_func(af.real(af.idft(af.dft(a))))

    a = af.randu(4, 4)
    display_func(a)

    display_func(af.fft2(a))
    display_func(af.dft(a))
    display_func(af.real(af.ifft2(af.fft2(a))))
    display_func(af.real(af.idft(af.dft(a))))

    a = af.randu(4, 4, 2)
    display_func(a)

    display_func(af.fft3(a))
    display_func(af.dft(a))
    display_func(af.real(af.ifft3(af.fft3(a))))
    display_func(af.real(af.idft(af.dft(a))))

    a = af.randu(10, 1)
    b = af.randu(3, 1)
    display_func(af.convolve1(a, b))
    display_func(af.fft_convolve1(a, b))
    display_func(af.convolve(a, b))
    display_func(af.fft_convolve(a, b))

    a = af.randu(5, 5)
    b = af.randu(3, 3)
    display_func(af.convolve2(a, b))
    display_func(af.fft_convolve2(a, b))
    display_func(af.convolve(a, b))
    display_func(af.fft_convolve(a, b))

    a = af.randu(5, 5, 3)
    b = af.randu(3, 3, 2)
    display_func(af.convolve3(a, b))
    display_func(af.fft_convolve3(a, b))
    display_func(af.convolve(a, b))
    display_func(af.fft_convolve(a, b))

    b = af.randu(3, 1)
    x = af.randu(10, 1)
    a = af.randu(2, 1)
    display_func(af.fir(b, x))
    display_func(af.iir(b, a, x))
af.display(af.fft2(a))
af.display(af.dft(a))
af.display(af.real(af.ifft2(af.fft2(a))))
af.display(af.real(af.idft(af.dft(a))))

a = af.randu(4, 4, 2)
af.display(a)

af.display(af.fft3(a))
af.display(af.dft(a))
af.display(af.real(af.ifft3(af.fft3(a))))
af.display(af.real(af.idft(af.dft(a))))

a = af.randu(10, 1)
b = af.randu(3, 1)
af.display(af.convolve1(a, b))
af.display(af.fft_convolve1(a, b))
af.display(af.convolve(a, b))
af.display(af.fft_convolve(a, b))

a = af.randu(5, 5)
b = af.randu(3, 3)
af.display(af.convolve2(a, b))
af.display(af.fft_convolve2(a, b))
af.display(af.convolve(a, b))
af.display(af.fft_convolve(a, b))

a = af.randu(5, 5, 3)
b = af.randu(3, 3, 2)
af.display(af.convolve3(a, b))
af.display(af.fft_convolve3(a, b))
Example #8
0
def simple_signal(verbose=False):
    display_func = _util.display_func(verbose)
    print_func   = _util.print_func(verbose)

    signal = af.randu(10)
    x_new  = af.randu(10)
    x_orig = af.randu(10)
    display_func(af.approx1(signal, x_new, xp = x_orig))

    signal = af.randu(3, 3)
    x_new  = af.randu(3, 3)
    x_orig = af.randu(3, 3)
    y_new  = af.randu(3, 3)
    y_orig = af.randu(3, 3)

    display_func(af.approx2(signal, x_new, y_new, xp = x_orig, yp = y_orig))

    a = af.randu(8, 1)
    display_func(a)

    display_func(af.fft(a))
    display_func(af.dft(a))
    display_func(af.real(af.ifft(af.fft(a))))
    display_func(af.real(af.idft(af.dft(a))))

    b = af.fft(a)
    af.ifft_inplace(b)
    display_func(b)
    af.fft_inplace(b)
    display_func(b)

    b = af.fft_r2c(a)
    c = af.fft_c2r(b)
    display_func(b)
    display_func(c)

    a = af.randu(4, 4)
    display_func(a)

    display_func(af.fft2(a))
    display_func(af.dft(a))
    display_func(af.real(af.ifft2(af.fft2(a))))
    display_func(af.real(af.idft(af.dft(a))))

    b = af.fft2(a)
    af.ifft2_inplace(b)
    display_func(b)
    af.fft2_inplace(b)
    display_func(b)

    b = af.fft2_r2c(a)
    c = af.fft2_c2r(b)
    display_func(b)
    display_func(c)

    a = af.randu(4, 4, 2)
    display_func(a)

    display_func(af.fft3(a))
    display_func(af.dft(a))
    display_func(af.real(af.ifft3(af.fft3(a))))
    display_func(af.real(af.idft(af.dft(a))))

    b = af.fft3(a)
    af.ifft3_inplace(b)
    display_func(b)
    af.fft3_inplace(b)
    display_func(b)

    b = af.fft3_r2c(a)
    c = af.fft3_c2r(b)
    display_func(b)
    display_func(c)

    a = af.randu(10, 1)
    b = af.randu(3, 1)
    display_func(af.convolve1(a, b))
    display_func(af.fft_convolve1(a, b))
    display_func(af.convolve(a, b))
    display_func(af.fft_convolve(a, b))

    a = af.randu(5, 5)
    b = af.randu(3, 3)
    display_func(af.convolve2(a, b))
    display_func(af.fft_convolve2(a, b))
    display_func(af.convolve(a, b))
    display_func(af.fft_convolve(a, b))

    a = af.randu(5, 5, 3)
    b = af.randu(3, 3, 2)
    display_func(af.convolve3(a, b))
    display_func(af.fft_convolve3(a, b))
    display_func(af.convolve(a, b))
    display_func(af.fft_convolve(a, b))


    b = af.randu(3, 1)
    x = af.randu(10, 1)
    a = af.randu(2, 1)
    display_func(af.fir(b, x))
    display_func(af.iir(b, a, x))

    display_func(af.medfilt1(a))
    display_func(af.medfilt2(a))
    display_func(af.medfilt(a))
Example #9
0
def simple_signal(verbose=False):
    display_func = _util.display_func(verbose)

    signal = af.randu(10)
    x_new = af.randu(10)
    x_orig = af.randu(10)
    display_func(af.approx1(signal, x_new, xp=x_orig))

    signal = af.randu(3, 3)
    x_new = af.randu(3, 3)
    x_orig = af.randu(3, 3)
    y_new = af.randu(3, 3)
    y_orig = af.randu(3, 3)

    display_func(af.approx2(signal, x_new, y_new, xp=x_orig, yp=y_orig))

    a = af.randu(8, 1)
    display_func(a)

    display_func(af.fft(a))
    display_func(af.dft(a))
    display_func(af.real(af.ifft(af.fft(a))))
    display_func(af.real(af.idft(af.dft(a))))

    b = af.fft(a)
    af.ifft_inplace(b)
    display_func(b)
    af.fft_inplace(b)
    display_func(b)

    b = af.fft_r2c(a)
    c = af.fft_c2r(b)
    display_func(b)
    display_func(c)

    a = af.randu(4, 4)
    display_func(a)

    display_func(af.fft2(a))
    display_func(af.dft(a))
    display_func(af.real(af.ifft2(af.fft2(a))))
    display_func(af.real(af.idft(af.dft(a))))

    b = af.fft2(a)
    af.ifft2_inplace(b)
    display_func(b)
    af.fft2_inplace(b)
    display_func(b)

    b = af.fft2_r2c(a)
    c = af.fft2_c2r(b)
    display_func(b)
    display_func(c)

    a = af.randu(4, 4, 2)
    display_func(a)

    display_func(af.fft3(a))
    display_func(af.dft(a))
    display_func(af.real(af.ifft3(af.fft3(a))))
    display_func(af.real(af.idft(af.dft(a))))

    b = af.fft3(a)
    af.ifft3_inplace(b)
    display_func(b)
    af.fft3_inplace(b)
    display_func(b)

    b = af.fft3_r2c(a)
    c = af.fft3_c2r(b)
    display_func(b)
    display_func(c)

    a = af.randu(10, 1)
    b = af.randu(3, 1)
    display_func(af.convolve1(a, b))
    display_func(af.fft_convolve1(a, b))
    display_func(af.convolve(a, b))
    display_func(af.fft_convolve(a, b))

    a = af.randu(5, 5)
    b = af.randu(3, 3)
    display_func(af.convolve2(a, b))
    display_func(af.fft_convolve2(a, b))
    display_func(af.convolve(a, b))
    display_func(af.fft_convolve(a, b))

    c = af.convolve2NN(a, b)
    display_func(c)
    in_dims = c.dims()
    incoming_grad = af.constant(1, in_dims[0], in_dims[1])
    g = af.convolve2GradientNN(incoming_grad, a, b, c)
    display_func(g)

    a = af.randu(5, 5, 3)
    b = af.randu(3, 3, 2)
    display_func(af.convolve3(a, b))
    display_func(af.fft_convolve3(a, b))
    display_func(af.convolve(a, b))
    display_func(af.fft_convolve(a, b))

    b = af.randu(3, 1)
    x = af.randu(10, 1)
    a = af.randu(2, 1)
    display_func(af.fir(b, x))
    display_func(af.iir(b, a, x))

    display_func(af.medfilt1(a))
    display_func(af.medfilt2(a))
    display_func(af.medfilt(a))