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[netCDFJava #SCH-111122]: Problem casting Array

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  • Subject: [netCDFJava #SCH-111122]: Problem casting Array
  • Date: Wed, 01 Aug 2007 08:25:33 -0600
Hi Philippe:

The most efficient solution:

  Array data = v.read();
  float[] fdata =(float []) data.get1DJavaArray(float.class);

this avoids copying if the data is already float.

However, you have a 1D array, not 2D. Since you are worried about efficiency,
the fastest thing to do is to work with the 1D array (ie dont use a 2D array),
and do the stride arithmetic yourself, so use fdata[j*nx+i] whenever you want
f[j][i], where nx = data.getShape()[1]. Im assuming you know these are 2D
arrays.

otherwise you have to allocate the 2D array and copy into it, in which case you
might as well do

  Index ima = data.getIndex();
  int [] shape = data.getShape();
  for (int j = 0; j<shape[0];  j++)
    for (int i = 0; i<shape[1];  i++)
      f[j][i] = data.getFloat( ima.set(j,i));

Regards,

John

Ticket Details
===================
Ticket ID: SCH-111122
Department: Support netCDF Java
Priority: Normal
Status: Open