RelIncreDisp

Relative Displacement Increment

In the governing equation,

$$\mathbf{K\cdot\Delta{}U=R},$$

this converger tests the following ratio,

$$\mathbf{\dfrac{\left|\Delta{}U^k\right|_\infty}{\left|\sum_{i=0}^{k}\Delta{}U^i\right|_\infty}}\leqslant{}tol.$$

where $\mathbf{\Delta{}U^k}$ denotes the displacement increment of the $k$-th iteration.