This is infinity (i.e. max norm) which is available for Array 3D, Vector and Matrix type.
For an Array 3D variable following equation is used.
$$ ||\underline{V}||_\infty = \max\left \lbrace {|V_X|, |V_Y|, |V_Z|}\right \rbrace$$
For a Vector variable following equation is used.
$$ ||\underline{V}||_\infty = \max\left \lbrace {|V_0|, |V_1|, |V_2|,...,{V_{n-1}}}\right \rbrace$$
For a Matrix variable following equation is used.
$$ ||\underline{A}||_\infty = \max_{0 \leq i < n}\left( \sum_{j=0}^{n-1} |a_{ij}|\right )$$