How to reduce the gap between plot title text and the legend in gnuplot?

Question

How can I reduce the gap between plot title text and the legend in gnuplot ?
For example in the following plot how do I reduce the gap between ABC* and circle symbol?

I am using ubuntu version 18.04 and gnuplot version 5.2.

Answer 1

There are a lot of customization options for the legend. One way to do it is to reduce the total width ("sample length") allocated for the symbol.

 set key samplen 0.5      # reduce sample length to half the default