Directional Strength or Digbala is one of the Sixfold strengths. Here we give the formula for computing Directional strength
First find out the Digbala arc. For instance Jupiter has full directional strength when he is on the Ascendant. That means 180 degrees from that point, on the Descendant he is zero.
So the equation for Digabala arc is
Digbala arc = Longitude of the planet – its powerless point.
( if the difference is more than 180, subtract it from 360 degrees ).
The midpoint of the House or Bhava is taken into consideration. The midpoint of the 7th House becomes the powerless point of Jupiter
Divide the Digbala arc by 3 and you get the Digbala or Directional strength.