Jmeter : Number of active threads

• I am using jmeter in elemetery freya (14.04)
• I have a jmeter test plan with view results tree
• I am trying to generate a csv file in view results tree including the number of active threads field.

• It appears to me that the detail is being entered in the result.csv file, but the values representing this attribute has no field name, and hence that detail cannot be used in a graph which I want to create from the result.csv

• I have changed JMETER-INSTALL-DIR/bin/jmeter.properties according to http://ift.tt/2hAMELH

• How can I get a result.csv file with a suitable fieldname like "active-threads"