naginterfaces.library.wav.dim2_​sngl_​inv

naginterfaces.library.wav.dim2_sngl_inv(m, n, ca, ch, cv, cd, comm)

dim2_sngl_inv computes the inverse two-dimensional discrete wavelet transform (DWT) at a single level. The initialization function dim2_init() must be called first to set up the DWT options.

For full information please refer to the NAG Library document for c09eb

https://support.nag.com/numeric/nl/nagdoc_30.3/flhtml/c09/c09ebf.html

Parameters

mint

Number of rows, $m$, of data matrix $B$.

nint

Number of columns, $n$, of data matrix $B$.

cafloat, array-like, shape $({\text{n}}_{\text{cm}},{\text{n}}_{\text{cn}})$

Contains the $n_{\text{cm}}\times n_{\text{cn}}$ matrix of approximation coefficients, $C_a$. This array will normally be the result of some transformation on the coefficients computed by function dim2_sngl_fwd().

chfloat, array-like, shape $({\text{n}}_{\text{cm}},{\text{n}}_{\text{cn}})$

Contains the $n_{\text{cm}}\times n_{\text{cn}}$ matrix of horizontal coefficients, $C_h$. This array will normally be the result of some transformation on the coefficients computed by function dim2_sngl_fwd().

cvfloat, array-like, shape $({\text{n}}_{\text{cm}},{\text{n}}_{\text{cn}})$

Contains the $n_{\text{cm}}\times n_{\text{cn}}$ matrix of vertical coefficients, $C_v$. This array will normally be the result of some transformation on the coefficients computed by function dim2_sngl_fwd().

cdfloat, array-like, shape $({\text{n}}_{\text{cm}},{\text{n}}_{\text{cn}})$

Contains the $n_{\text{cm}}\times n_{\text{cn}}$ matrix of diagonal coefficients, $C_d$. This array will normally be the result of some transformation on the coefficients computed by function dim2_sngl_fwd().

commdict, communication object

Communication structure.

This argument must have been initialized by a prior call to dim2_init().

Returns

bfloat, ndarray, shape $(m,n)$

The $m\times n$ reconstructed matrix, $B$, based on the input approximation, horizontal, vertical and diagonal coefficients and the transform options supplied to the initialization function dim2_init().

Raises

NagValueError

(errno $4$)

On entry, $n=⟨value⟩$.

Constraint: $n=⟨value⟩$, the value of $\text{n}$ on initialization (see dim2_init()).

(errno $4$)

On entry, $m=⟨value⟩$.

Constraint: $m=⟨value⟩$, the value of $\text{m}$ on initialization (see dim2_init()).

(errno $6$)

Either the initialization function has not been called first or $comm$[‘icomm’] has been corrupted.

(errno $6$)

Either the initialization function was called with $wtrans=\text{‘M'}$ or $comm$[‘icomm’] has been corrupted.

Notes

dim2_sngl_inv performs the inverse operation of function dim2_sngl_fwd(). That is, given sets of approximation, horizontal, vertical and diagonal coefficients computed by function dim2_sngl_fwd() using a DWT as set up by the initialization function dim2_init(), on a real matrix, $B$, dim2_sngl_inv will reconstruct $B$.