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/*
* Copyright (c) 1998-2018 John Caron and University Corporation for Atmospheric Research/Unidata
* See LICENSE for license information.
*/
package ucar.nc2.write;
import ucar.nc2.Variable;
/**
* chunk on last 2 dimensions, like GRIB
*
* @author caron
* @since 11/26/12
*/
public class Nc4ChunkingStrategyGrib extends Nc4ChunkingDefault {
public Nc4ChunkingStrategyGrib(int deflateLevel, boolean shuffle) {
super(deflateLevel, shuffle);
}
@Override
public boolean isChunked(Variable v) {
if (v.isUnlimited()) return true;
// if (getChunkAttribute(v) != null) return true;
int n = v.getRank();
return n >= 2 && v.getSize() * v.getElementSize() > getMinVariableSize();
}
@Override
public long[] computeChunking(Variable v) {
/* check attribute
int[] resultFromAtt = computeChunkingFromAttribute(v);
if (resultFromAtt != null)
return convertToLong(resultFromAtt); */
// no unlimited dimensions
if (!v.isUnlimited()) {
int[] result = computeChunkingGrib(v);
return convertToLong(result);
}
// unlimited case
if (v.getRank() >= 2) {
long varSize = v.getSize() * v.getElementSize();
if (varSize > getMinVariableSize()) // getMinVariableSize or getMinChunksize ??
return convertToLong(computeChunkingGrib(v));
}
// small unlimited variable
int[] result = computeUnlimitedChunking(v.getDimensions(), v.getElementSize());
return convertToLong(result);
}
private int[] computeChunkingGrib(Variable v) {
int n = v.getRank();
int[] result = new int[n];
if( n < 2 ) {
result[0] = 1; // Unlimited variable with rank 1
} else {
for (int i=0; i