IDL Wavelet Toolkit User's Guide

74 Chapter 4: IDL Wavelet Toolkit ReferenceWV_DWTThe WV_DWT function returns the multi-dimensional discrete wavelet transform ofthe input Array. The transform is done by WV_PWT using a user-inputted waveletfilter.The length of each dimension of Array must be either a power of two (2), or must beless than four (4). The transform is not computed over dimensions of lengths less thanfour (4), but is computed over all other dimensions (for example, the wavelettransform of an array of size [3, 256] is computed over each [1, 256] column vector).WV_DWT is based on the routine wtn described in section 13.10 of NumericalRecipes in C: The Art of Scientific Computing, 2nd ed. (Cambridge University Press),and is used by permission.SyntaxResult = WV_DWT(Array, Scaling, Wavelet, Ioff, Joff [, /DOUBLE] [, /INVERSE][, N_LEVELS=value])Return ValueThe result is an output array of the same dimensions as Array, containing the discretewavelet transform over each dimension.ArgumentsArrayThe input vector or array. The length of each dimension must be either less than four(4) or a power of two (2).ScalingA vector of scaling (father) coefficients, of length N.WaveletA vector of wavelet (mother) coefficients, of length N.WV_DWTIDL Wavelet Toolkit