Not able to log "throughput" in a log file

[vivek]

Hi,

I am not able to log the throughput during the run in a log file. I can 
see the values in the in "aggregate results" but cannot find in log file.

I want to log the *timestamp , throughput *in a file for a particular 
JMeter run.

Please help.

Thanks,
vivek kumar singh
National University of Singapore