Algebraic and differential operators evalution rules#

Evaluation of the \(\mathrm{grad}\) operator#

Rule ID

symbolic expression

evaluation

[OG1]

\(\mathrm{grad}(f+g)\)

\(\mathrm{grad}(f) + \mathrm{grad}(g)\)

[OG2]

\(\mathrm{grad}(\alpha ~ f)\)

\(\alpha~\mathrm{grad}(f)\)

[OG3]

\(\mathrm{grad}(f ~ g)\)

\(f~\mathrm{grad}(g) + g~\mathrm{grad}(f)\)

[OG4]

\(\mathrm{grad}(\frac{f}{g})\)

\(-\frac{f}{g^2}\mathrm{grad}(g) + \frac{1}{g}\mathrm{grad}(f)\)

[OG5]

\(\mathrm{grad}(F+G)\)

\(\mathrm{grad}(F) + \mathrm{grad}(G)\)

[OG6]

\(\mathrm{grad}(\alpha ~ F)\)

\(\alpha~\mathrm{grad}(F)\)

[OG7]

\(\mathrm{grad}(\mathrm{dot}(F, G))\)

\(\mathrm{convect}(F, G) + \mathrm{convect}(G, F) + \mathrm{cross}(F, \mathrm{curl}(G)) - \mathrm{cross}(\mathrm{curl}(F), G)\)

Evaluation of \(\mathrm{curl}\) and \(\mathrm{rot}\) operators in 2D#

Rule ID

symbolic expression

evaluation

[OC1a]

\(\mathrm{curl}(f+g)\)

\(\mathrm{curl}(f) + \mathrm{curl}(g)\)

[OC2a]

\(\mathrm{curl}(\alpha ~ f)\)

\(\alpha~\mathrm{curl}(f)\)

[OC1b]

\(\mathrm{rot}(F+G)\)

\(\mathrm{rot}(F) + \mathrm{rot}(G)\)

[OC2b]

\(\mathrm{rot}(\alpha ~ F)\)

\(\alpha~\mathrm{rot}(F)\)

Evaluation of \(\mathrm{curl}\) operator in 3D#

Rule ID

symbolic expression

evaluation

[OC1]

\(\mathrm{curl}(F+G)\)

\(\mathrm{curl}(F) + \mathrm{curl}(G)\)

[OC2]

\(\mathrm{curl}(\alpha ~ F)\)

\(\alpha~\mathrm{curl}(F)\)

[OC3]

\(\mathrm{curl}(f ~ F)\)

\(f~\mathrm{curl}(F) + \mathrm{cross}(\mathrm{grad}(f), F)\)

[OC4]

\(\mathrm{curl}(\mathrm{cross}(F, G))\)

\(\mathrm{div}(G)~F - \mathrm{div}(F)~G - \mathrm{convect}(F, G) +\mathrm{convect}(G, F)\)

Evaluation of \(\mathrm{div}\) operator#

Rule ID

symbolic expression

evaluation

[OD1]

\(\mathrm{div}(F+G)\)

\(\mathrm{div}(F) + \mathrm{div}(G)\)

[OD2]

\(\mathrm{div}(\alpha ~ F)\)

\(\alpha~\mathrm{div}(F)\)

[OD3]

\(\mathrm{div}(f ~ G)\)

\(f~\mathrm{div}(G) + \mathrm{dot}(G, \mathrm{grad}(f))\)

[OD4]

\(\mathrm{div}(\mathrm{cross}(F, G))\)

\(-\mathrm{dot}(F, \mathrm{curl}(G)) + \mathrm{dot}(G, \mathrm{curl}(F))\)

Evaluation of \(\mathrm{laplace}\) operator#

Rule ID

symbolic expression

evaluation

[OL1]

\(\mathrm{laplace}(f+g)\)

\(\mathrm{laplace}(f) + \mathrm{laplace}(g)\)

[OL2]

\(\mathrm{laplace}(\alpha ~ f)\)

\(\alpha~\mathrm{laplace}(f)\)

[OL3]

\(\mathrm{laplace}(f~g)\)

\(f ~ \mathrm{laplace}(g) + g ~ \mathrm{laplace}(f) + 2 \mathrm{dot}(\mathrm{grad}(f), \mathrm{grad}(g))\)

Evaluation of specific combination of operators#

Rule ID

symbolic expression

evaluation

[OS1]

\(\mathrm{curl}(\mathrm{grad}(f))\)

\(0\)

[OS2]

\(\mathrm{div}(\mathrm{curl}(F))\)

\(0\)

[OS3]

\(\mathrm{div}(\mathrm{cross}(\mathrm{grad}(F), \mathrm{grad}(G)))\)

\(0\)

[OS4]

\(\mathrm{curl}(\mathrm{curl}(F))\)

\(\mathrm{grad}(\mathrm{div}(F)) - \mathrm{laplace}(F)\)

[OS5]

\(\mathrm{curl}(f~\mathrm{grad}(g))\)

\(\mathrm{cross}(\mathrm{grad}(f), \mathrm{grad}(g))\)