# detcoef

1-D detail coefficients

## Syntax

`D = detcoef(C,L,N)D = detcoef(C,L)`

## Description

`detcoef` is a one-dimensional wavelet analysis function.

`D = detcoef(C,L,N)` extracts the detail coefficients at level `N` from the wavelet decomposition structure `[C,L]`. See `wavedec` for more information on `C` and `L`.

Level `N` must be an integer such that `1 `` N ``NMAX `where `NMAX` = `length(L)-2`.

`D = detcoef(C,L)` extracts the detail coefficients at last level `NMAX`.

If `N` is a vector of integers such that 1 ≤ `N(j)``NMAX`:

• `DCELL = detcoef(C,L,N,'cells')` returns a cell array where `DCELL{j}` contains the coefficients of detail `N(j)`.

• If `length(N) > 1`, ```DCELL = detcoef(C,L,N)``` is equivalent to `DCELL = detcoef(C,L,N,'cells')`.

• `DCELL = detcoef(C,L,'cells')` is equivalent to `DCELL = detcoef(C,L,[1:NMAX])`.

• `[D1, ... ,Dp] = detcoef(C,L,[N(1), ... ,N(p)])` extracts the details coefficients at levels `[N(1), ... ,N(p)]`.

## Examples

```% The current extension mode is zero-padding (see dwtmode). % Load original one-dimensional signal. load leleccum; s = leleccum(1:3920); % Perform decomposition at level 3 of s using db1. [c,l] = wavedec(s,3,'db1'); % Extract detail coefficients at levels % 1, 2 and 3, from wavelet decomposition % structure [c,l]. [cd1,cd2,cd3] = detcoef(c,l,[1 2 3]); % Using some plotting commands, % the following figure is generated. ```