Source directory /data/lofarschool/data/Exercise-CR1
Contact person Andreas Horneffer, Lars Bähren

This exercise demonstrates the usage of the DataReader and its ability to abstract the file format from the user.


  • Some C/C++ programming.
  • Installed USG software (CR-Tools package)
  • Successful completion of Exercise CR0

In this exercise you use the DataReader to open different types of files with time-series data and make some simple plots.

|-- 2006.02.23.04:02:50.283.event
|-- rw_20071121
|   `-- rw_20071121_000001_0100.dat
`-- rw_20080701_162002_0109.h5

And the exercise_cr1 executable.

  1. Execute the exercise_cr1 executable
    • This produces some output and some plots in postscript files
  2. Check in the source code how this is done.
  3. Modify the source, compile it, and see what it does.
    • Check the documentation of the DataReader to, e.g., change the block-size, block number, or plot different data.

The unmodified exercise_cr1 executable should produce the following output and six postscript files:

(horneffer)lioff024> ./exercise_cr1          
Loading LOPES event.                         
genOutput: Observatory: LOPES                
           Date: 1140667370                  
           Filesize: 65536                   
           plotting voltage, #xpoints:65536 #ypoints:65536
           plotting FFT, #xpoints:32769 #ypoints:32769    
Loading raw tbbctl data.                                  
genOutput: Observatory: LOFAR                             
           Date: 1195603201                               
           Filesize: 2048000                              
           plotting voltage, #xpoints:2048000 #ypoints:2048000
           plotting FFT, #xpoints:1024001 #ypoints:1024001    
Loading LOFAR hdf5 data.                                      
-- nof dipole datasets = 1
-- sample frequencies = [200]
-- Setting up DataIterator objects ...
-- Setting up header record ...
genOutput: Observatory: LOFAR
           Date: 1214929202
           Filesize: 2048000
           plotting voltage, #xpoints:2048 #ypoints:2048
           plotting FFT, #xpoints:1025 #ypoints:1025

If you are experiencing trouble getting the exercise to work, this is the place to leave a note about it.

  • Last modified: 2017-03-08 15:27
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