Purpose

This thorn registers a number of reduction operators with the flesh. The reductions are performed using internals of the PUGH driver, so that this thorn can only be used when CactusPUGH/PUGH is active.

The reduction operations this thorn registers are

Reduction Operator	Calculates	By
average$^*$, mean$^*$	the average/mean of a grid variable	$\sum{ GV }/N$
count	the number of grid points in a grid variable	$N$
maximum$^*$	the maximum of a grid variable	$\max{ GV }$
minimum$^*$	the minimum of a grid variable	$\min{ GV }$
norm1, L1Norm	the L1 norm of a grid variable	$\left(\Sigma \vert GV\vert \right)/N$
norm2, L2Norm	the L2 norm of a grid variable	$\sqrt[2]{(\Sigma \vert GV\vert^2)/N}$
norm3, L3Norm	the L3 norm of a grid variable	$\sqrt[3]{(\Sigma \vert GV\vert^3)/N}$
norm4, L4Norm	the L4 norm of a grid variable	$\sqrt[4]{(\Sigma \vert GV\vert^4)/N}$
norm_inf, LinfNorm	the Infinitity norm of a grid variable	$\max{\vert GV \vert}$
sum$^*$	the sum of the elements of a grid variable	$\sum{ GV }$

Reduction operators with multiple names are just synonyms for the same kind of reduction operation. In the formulas $GV$ is the grid variable to be reduced, and $N$ denotes the number of its elements. Reduction operators marked with $^*$ cannot be applied to grid variables of complex datatype.