2.1.22.2.1.1 apply_window_data

Description

Apply window to the signal.

Syntax

int apply_window_data( vector & vSignal, int nType, double * pdCom = NULL )

Parameters

vSignal

[modify] the original signal to be transformed, and the result of the transform.

nType

[input] the window method, now it can be one of the following,

Rectangle_Win, Create a Rectangle Window

Welch_Win, Create a Welch Window

Triangular_Win, Create a Triangular Window

Bartlett_Win, Create a Bartlett Window

Hanning_Win, Create a Hanning Window

Hamming_Win, Create a Hamming Window

Blackman_Win, Create a Blackman Window

Gaussian_Win, Create a Gaussian Window

Kaiser_Win, Create a Kaiser Window

pdCom

[output] pointer to a data who will compensate the tapering caused by applying window in FFT

Return

Returns OE_NOERROR for success or error codes for failure.

Examples

Prior to compilation, load fft_utils.c to the workspace by executing the following LabTalk command:

Run.LoadOC("Originlab\fft_utils.c", 16);

To retain fft_utils.c in the workspace for successive sessions, drag and drop the file from the Temporary folder to the System folder.

EX1

 
#include <fft_utils.h>
void apply_window_data_ex1()
{
    //enum {                         // Window method
            //Rectangle_Win = 0,
            //Welch_Win,
            //Triangular_Win,
            //Bartlett_Win,
            //Hanning_Win,
            //Hamming_Win,
            //Blackman_Win,
            //Gaussian_Win,
            //Kaiser_Win,
    //};

    int nType = 1;
    // Create a new worksheet and import data
    WorksheetPage wpg;
    wpg.Create("Origin");
    Worksheet wks = wpg.Layers(0);
    string strFile = GetAppPath(TRUE) + "Samples\\Signal Processing\\Signal with Discrete Frequencies.dat";
    ASCIMP    ascimp;
    wks.GetASCIMP(ascimp);
    if( 0 != wks.ImportASCII(strFile, ascimp) )
    {
        out_str("Failed to import file");
        return;
    }
    
    // Add another column for convolution output
    uint nIndex = wks.AddCol();
    wks.Columns(nIndex).SetLongName("ApplyWindow");
    
    // Set up datasets and vectors for function call
    Dataset dsSignal(wks, 1);
    Dataset dsResult(wks, 2);    
    vector vecSignal(dsSignal), vecResult;
    vecResult = vecSignal;
    
    // apply window to the signal
    int iRet = apply_window_data(vecResult, nType);
    if( 0 != iRet )
    {
        printf("apply_window_data function returned error: %d\n", iRet);
        return;
    }
    
    // Copy result to dataset
    dsResult = vecResult;
}

Remark

See Also

get_window_data

Header to Include

fft_utils.h

Reference