function s = cascade ( n, t, c ) %*****************************************************************************80 % %% CASCADE carries out the cascade algorithm. % % Discussion: % % The value of T3 computed by % % t3 = cascade ( 3, t0, c ) % % will be the same if computed in three steps by: % % t1 = cascade ( 1, t0, c ); % t2 = cascade ( 1, t1, c ); % t3 = cascade ( 1, t2, c ); % % If C represents a vector of Daubechies filter coefficients, then % % c5 = cascade ( 5, c, c ); % % computes an approximation to the corresponding scaling function, and % % w(1:2:nw-1) = - c(n :-2:2); % w(2:2:nw ) = c(n-1:-2:1); % w5 = cascade ( 5, w, c ); % % computes an approximation to the corresponding wavelet. % % Licensing: % % This code is distributed under the GNU LGPL license. % % Modified: % % 03 August 2011 % % Author: % % John Burkardt % % Parameters: % % Input, integer N, the number of iterations to carry out. % 0 <= N. % % Input, real T(P), the initial value of the quantity, or the % value of the quantity at the integers 0 through P-1. % % Input, real C(K), the transform coefficients. % % Output, real S(2^N * P + (2^N-1)*C_LENGTH - 2*(2^N-1)), the values of % the function. % s = t; for i = 1 : n nx = length ( s ) * 2 - 1; x(1:2:nx) = s; x(2:2:nx-1) = 0; s = conv ( x, c ); end % % Force S to be a column vector. % s = s ( : ); return end