nag_imldwt (c09cdc) computes the inverse one-dimensional multi-level discrete wavelet transform (DWT). This function reconstructs data from (possibly filtered or otherwise manipulated) wavelet transform coefficients calculated by
nag_mldwt (c09ccc) from an original set of data. The initialization function
nag_wfilt (c09aac) must be called first to set up the DWT options.
nag_imldwt (c09cdc) performs the inverse operation of
nag_mldwt (c09ccc). That is, given a set of wavelet coefficients, computed up to level
by
nag_mldwt (c09ccc) using a DWT as set up by the initialization function
nag_wfilt (c09aac), on a real data array of length
,
nag_imldwt (c09cdc) will reconstruct the data array
, for
,
from which the coefficients were derived. If the original input dataset is level
, then it is possible to terminate reconstruction at a higher level by specifying fewer than the number of levels used in the call to
nag_mldwt (c09ccc). This results in a partial reconstruction.
None.
The accuracy of the wavelet transform depends only on the floating-point operations used in the convolution and downsampling and should thus be close to machine precision.
None.