# ball extra command

Syntax

ball extra i a<range>

Set ball extra variables. The extra variable a can be of any type and is associated with the index i as if stored in an array.

Usage Example

Set the extra variable at index position 1 to 0 for all balls whose centroid’s $$z$$-coordinate lies between the values defined for the FISH symbols z1 and z2.

ball extra 1 0 range position-z [z1] [z2]


from “array_strength.dat” in Strength of a Face-Centered Cubic Array of Spheres

Set the extra variable at index position 5 to the vector (90,100,110) for all balls.

ball extra 5 (90,100,110)


Set the extra variable at index position 1 to the string Fred for all balls.

ball extra 1 'Fred'