Interpolation of data in Qwt Raster Matrix Data

[burger_major]

Uwe,

Thank you for your reply. According to the article, Bilinear interpolation is what I am looking for, but I have troubles with switching from default nearest neighbour resampling mode to the bilinear interpolation.

QVector <double> values;
    for(int i=-25; i<25; i++)
    {
    values.push_back(i*i);
    }
    QwtMatrixRasterData *m = new QwtMatrixRasterData;
    m->setValueMatrix(values,5);
    m->setResampleMode(m->BilinearInterpolation);

QVector <double> values;
    for(int i=-25; i<25; i++)
    {
    values.push_back(i*i);
    }
    QwtMatrixRasterData *m = new QwtMatrixRasterData;
    m->setValueMatrix(values,5);
    m->setResampleMode(m->BilinearInterpolation);

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changing resample mode in that way doesn't seem to give any changes to data presentation.