The correct usage of nested #pragma omp for directives
- by GoldenLee
The following code runs like a charm before OpenMP parallelization was applied. In fact, the following code was in a state of endless loop! I'm sure that's result from my incorrect use to the OpenMP directives. Would you please show me the correct way? Thank you very much.
#pragma omp parallel for
for (int nY = nYTop; nY <= nYBottom; nY++)
{
for (int nX = nXLeft; nX <= nXRight; nX++)
{
// Use look-up table for performance
dLon = theApp.m_LonLatLUT.LonGrid()[nY][nX] + m_FavoriteSVISSRParams.m_dNadirLon;
dLat = theApp.m_LonLatLUT.LatGrid()[nY][nX];
// If you don't want to use longitude/latitude look-up table, uncomment the following line
//NOMGeoLocate.XYToGEO(dLon, dLat, nX, nY);
if (dLon > 180 || dLat > 180)
{
continue;
}
if (Navigation.GeoToXY(dX, dY, dLon, dLat, 0) > 0)
{
continue;
}
// Skip void data scanline
dY = dY - nScanlineOffset;
// Compute coefficients as well as its four neighboring points' values
nX1 = int(dX);
nX2 = nX1 + 1;
nY1 = int(dY);
nY2 = nY1 + 1;
dCx = dX - nX1;
dCy = dY - nY1;
dP1 = pIRChannelData->operator [](nY1)[nX1];
dP2 = pIRChannelData->operator [](nY1)[nX2];
dP3 = pIRChannelData->operator [](nY2)[nX1];
dP4 = pIRChannelData->operator [](nY2)[nX2];
// Bilinear interpolation
usNomDataBlock[nY][nX] = (unsigned short)BilinearInterpolation(dCx, dCy, dP1, dP2, dP3, dP4);
}
}
