# Other functions

## Single-level n-dimensional Discrete Wavelet Transform.

`pywt.``dwtn`(data, wavelet[, mode='sym'])

  Performs single-level n-dimensional Discrete Wavelet Transform.

  Parameters:

  - data – n-dimensional array
  - wavelet – Wavelet to use in the transform. This can be a name of the wavelet from the `wavelist()` list or a `Wavelet` object instance.
  - mode – Signal extension mode to deal with the border distortion problem. See MODES for details.

  Results are arranged in a dictionary, where key specifies the transform type on each dimension and value is a n-dimensional coefficients array.

  For example, for a 2D case the result will look something like this:

      {
          'aa': <coeffs>  # A(LL) - approx. on 1st dim, approx. on 2nd dim
          'ad': <coeffs>  # H(LH) - approx. on 1st dim, det. on 2nd dim
          'da': <coeffs>  # V(HL) - det. on 1st dim, approx. on 2nd dim
          'dd': <coeffs>  # D(HH) - det. on 1st dim, det. on 2nd dim
      }

## Integrating wavelet functions - `intwave()`

`pywt.``intwave`(wavelet[, precision=8])

  Integration of wavelet function approximations as well as any other signals can be performed using the `pywt.intwave()` function.

  The result of the call depends on the wavelet argument:

  - for orthogonal wavelets - an integral of the wavelet function specified on an x-grid:

        [int_psi, x] = intwave(wavelet, precision)

  - for other wavelets - integrals of decomposition and reconstruction wavelet functions and a corresponding x-grid:

        [int_psi_d, int_psi_r, x] = intwave(wavelet, precision)

  - for a tuple of coefficients data and a x-grid - an integral of function and the given x-grid is returned (the x-grid is used for computations).:

        [int_function, x] = intwave((data, x), precision)

  Example:

      >>> import pywt
      >>> wavelet1 = pywt.Wavelet('db2')
      >>> [int_psi, x] = pywt.intwave(wavelet1, precision=5)
      >>> wavelet2 = pywt.Wavelet('bior1.3')
      >>> [int_psi_d, int_psi_r, x] = pywt.intwave(wavelet2, precision=5)

## Central frequency of psi wavelet function

`pywt.``centfrq`(wavelet[, precision=8])
`pywt.``centfrq`((function_approx, x))

  Parameters:

  - wavelet – `Wavelet`, wavelet name string or (wavelet function approx., x grid) pair
  - precision – Precision that will be used for wavelet function approximation computed with the `Wavelet.wavefun()` method.