HARK version 1.1.0 Document : PowerCalcForMap

6.7.7 PowerCalcForMap

Outline of the node

This node converts multichannel complex spectra of Map<int, ObjectRef> type IDs into real power spectra.

Necessary files

No files are required.

Usage

When to use

This node is used to convert complex spectra into real power spectra when inputs are Map<int, ObjectRef> type. When inputs are of Matrix<complex<float> > type, use the PowerCalcForMatrix node.

Typical connection

Figure 6.90 shows an example of the usage of the PowerCalcForMap node. A Map<int, ObjectRef> type complex spectrum obtained from the MultiFFT node is converted into Map<int, ObjectRef> type power spectrum and input to the MelFilterBank node.

$\includegraphics[width=.8\textwidth ]{fig/modules/PowerCalcForMap}$

Figure 6.90: Example of a connection of PowerCalcForMap

Input-output and properties of the node

Input

INPUT: Map<int, ObjectRef> type. Complex matrices of Matrix<complex<float> > type are stored in the ObjectRef part.

Output

OUTPUT: Map<int, ObjectRef> type. Real matrices of absolute values are stored in the ObjectRef part for each element of the complex matrices of the inputs.

Parameter

No parameters.

Details of the node

The real matrix $N_{i,j}$ of the output for the complex matrix $M_{i,j}$ of an input ( $i, j$ indicating the rows and columns of the index, respectively) is obtained as

$\displaystyle N_{i,j}$

$\displaystyle =$

$\displaystyle M_{i,j}M_{i,j}^{*},$

Here, $M_{i,j}^{*}$ indicates the complex conjugate of $M_{i,j}$ .