I’m receiving a network error when running an aggregate query using the Amazon VM. I’m running version 13.12 on one m3.2xlarge instance, and I’ve managed to produce the error with the following script.
What I’m ultimately trying to do is load 250 m MODIS data that comes in 4800x4800 rasters. Each file is a 16 day composite, so there are two images per month. I want to load a year worth of rasters (eventually multiple years, but one to start) and compute the average EVI value for each pixel in each month. I’ve set up my array with four dimensions: year, month, day, pixel index, and one attribute: Enhanced Vegetation Index (EVI). I want to run an aggregation by year and day to get the average EVI for each month at each pixel.
I’m running the following commands to set up an array with some dummy data and run the aggregation.
#!/bin/bash set -x # Cleanup iquery -anq "remove(mod13q1_test)" &> /dev/null iquery -anq "remove(mod13q1_test_climate)" &> /dev/null # Generate an array of test data time iquery -anq " store( build(<evi:int16> [year=2001:2001,1,0, month=1:12,12,0, doy=1:2,2,0, i=0:23039999,170000,0], month + i), mod13q1_test)" # Compute mean EVI for each pixel in each month. time iquery -anq " store( aggregate( mod13q1_test, avg(evi), stdev(evi), month, i), mod13q1_test_climate)"
This is the output that I receive:
+ iquery -anq ' store( build(<evi:int16> [year=2001:2001,1,0, month=1:12,12,0, doy=1:2,2,0, i=0:23039999,170000,0], month + i), mod13q1_test)' Query was executed successfully + iquery -anq ' store( aggregate( mod13q1_test, avg(evi), stdev(evi), month, i), mod13q1_test_climate)' SystemException in file: src/network/BaseConnection.h function: receive line: 294 Error id: scidb::SCIDB_SE_NETWORK::SCIDB_LE_CANT_SEND_RECEIVE Error description: Network error. Cannot send or receive network messages.
I don’t get the error every time that I run the script, but sometimes the operation takes over an hour to complete. Anyone know what’s going on here, or what I can try to get more information?