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Hi, I'm writing an application that reads data from NetCDF files and produces images. I've noticed (through profiling) that a slow point in the data reading process is the unpacking of packed data (i.e. applying scale and offset) and checking for missing values. I would like to minimize the use of these calls. To cut a long post short, I would like to find a low-level function that allows me to read the packed data, exactly as they appear in the file. I can then "manually" apply the unpacking and missing-value checks only to those data points that I need to display. I'm using nj22, version 2.2.16. I've tried reading data from GeoGrid.subset() but this (of course) performs the unpacking. I then tried getting the "unenhanced" variable object through GeoGrid.getVariable().getOriginalVariable(), but (unexpectedly) this also seems to perform unpacking and missing-value checks - I expected it to give raw data. Can anyone help me to find a function for reading raw (packed) data without performing missing-value checks? Thanks in advance, Jon -- -------------------------------------------------------------- Dr Jon Blower Tel: +44 118 378 5213 (direct line) Technical Director Tel: +44 118 378 8741 (ESSC) Reading e-Science Centre Fax: +44 118 378 6413 ESSC Email: jdb@xxxxxxxxxxxxxxxxxxxx University of Reading 3 Earley Gate Reading RG6 6AL, UK -------------------------------------------------------------- ============================================================================== To unsubscribe netcdf-java, visit: http://www.unidata.ucar.edu/mailing-list-delete-form.html ==============================================================================
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