To: address@hidden
From: "Michael P Duff" <address@hidden>
Subject: Netcdf Java problem
Organization: UCAR/Unidata
Keywords: 200107111340.f6BDeO122826
Hi Mike,
Hi. I am having a problem with the NetCDF Java version 2. I am reading
data from an existing NetCDF file using the read() function to place the
data into an Array. The data is stored as a double in the Netcdf file. I
then use the IndexIterator to step through the Array. I get a compile
error. I am using the code I found in the API for the Interface
IndexIterator, the "Replace array with its square" example. The program
works if I just print the values instead of put them into a variable. I
have below my code, my compile error and the "Replace array with its
square" example. I would appreciate any help you can give me.
Thank you,
Mike
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// My code that gets a compile error
import ucar.ma2.*;
import ucar.nc2.*;
import java.io.*;
import java.util.*;
public class ncproblem {
public static void main(String[] args) {
try {
NetcdfFile nc = new NetcdfFile(args[0]);
System.out.println(nc);
Variable heightVar = nc.findVariable("height");
System.out.println(heightVar);
int[] origin = new int[4];
origin[0] = 45000;
int[] shape = new int[4];
shape[0] = 50;
for (int i = 1; i<4; i+=1){
origin[i] = 1;
shape[i] = 1;
}
Array hgtVals = heightVar.read(origin,shape);
IndexIterator iter = hgtVals.getIndexIterator();
while(iter.hasNext()) {
for(int i=0; i<50; i+=1) {
Double val = iter.getDoubleNext();
System.out.println(val + ",");
}
}
}catch (java.io.IOException e) {
e.printStackTrace();
}
}
}
------------------------------------------------------------------------------------------------------------------------------
The compile error is:
incompatible types
found : double
required: java.lang.Double
Double val = iter.getDoubleNext();
^
1 error
------------------------------------------------------------------------------------------------------------------------------
Since IndexIterator.getDoubleNext() returns double rather than Double,
you need to change this statement to:
double val = iter.getDoubleNext();
After that, you'll get another compile error because the read() method
can generate an InvalidRangeException, which is not a java.io.IOException:
ncproblem.java:23: unreported exception ucar.ma2.InvalidRangeException; must
be caught or declared to be thrown
Array hgtVals = heightVar.read(origin,shape);
^
One (crude) way to handle this would be to change your catch statement to:
}catch (Exception e) {
--Russ