# struct.shell.beta

Syntax

f := struct.shell.beta(p)
struct.shell.beta(p) := f

Get/set shell-type material system beta angle. This is defined as the angle between the element local system $$x$$-axis and the material system $$x$$-axis. In radians measured counter-clockwise from the element local $$x$$-axis.

Modifying the stiffness of an element can result in instability if done during cycling. Dependent values should be forced to update using struct.force.update. See the documentation of struct.force.update for comments on the cost.

Returns: f - the shell material system beta angle in radians f - the shell material system beta angle in radians p - a pointer to a shell element