Algebraic and differential operators evalution rules#
Evaluation of the \(\mathrm{grad}\) operator#
Rule ID |
symbolic expression |
evaluation |
---|---|---|
|
\(\mathrm{grad}(f+g)\) |
\(\mathrm{grad}(f) + \mathrm{grad}(g)\) |
|
\(\mathrm{grad}(\alpha ~ f)\) |
\(\alpha~\mathrm{grad}(f)\) |
|
\(\mathrm{grad}(f ~ g)\) |
\(f~\mathrm{grad}(g) + g~\mathrm{grad}(f)\) |
|
\(\mathrm{grad}(\frac{f}{g})\) |
\(-\frac{f}{g^2}\mathrm{grad}(g) + \frac{1}{g}\mathrm{grad}(f)\) |
|
\(\mathrm{grad}(F+G)\) |
\(\mathrm{grad}(F) + \mathrm{grad}(G)\) |
|
\(\mathrm{grad}(\alpha ~ F)\) |
\(\alpha~\mathrm{grad}(F)\) |
|
\(\mathrm{grad}(\mathrm{dot}(F, G))\) |
\(\mathrm{convect}(F, G) + \mathrm{convect}(G, F) + \mathrm{cross}(F, \mathrm{curl}(G)) - \mathrm{cross}(\mathrm{curl}(F), G)\) |
Evaluation of \(\mathrm{curl}\) and \(\mathrm{rot}\) operators in 2D#
Rule ID |
symbolic expression |
evaluation |
---|---|---|
|
\(\mathrm{curl}(f+g)\) |
\(\mathrm{curl}(f) + \mathrm{curl}(g)\) |
|
\(\mathrm{curl}(\alpha ~ f)\) |
\(\alpha~\mathrm{curl}(f)\) |
|
\(\mathrm{rot}(F+G)\) |
\(\mathrm{rot}(F) + \mathrm{rot}(G)\) |
|
\(\mathrm{rot}(\alpha ~ F)\) |
\(\alpha~\mathrm{rot}(F)\) |
Evaluation of \(\mathrm{curl}\) operator in 3D#
Rule ID |
symbolic expression |
evaluation |
---|---|---|
|
\(\mathrm{curl}(F+G)\) |
\(\mathrm{curl}(F) + \mathrm{curl}(G)\) |
|
\(\mathrm{curl}(\alpha ~ F)\) |
\(\alpha~\mathrm{curl}(F)\) |
|
\(\mathrm{curl}(f ~ F)\) |
\(f~\mathrm{curl}(F) + \mathrm{cross}(\mathrm{grad}(f), F)\) |
|
\(\mathrm{curl}(\mathrm{cross}(F, G))\) |
\(\mathrm{div}(G)~F - \mathrm{div}(F)~G - \mathrm{convect}(F, G) +\mathrm{convect}(G, F)\) |
Evaluation of \(\mathrm{div}\) operator#
Rule ID |
symbolic expression |
evaluation |
---|---|---|
|
\(\mathrm{div}(F+G)\) |
\(\mathrm{div}(F) + \mathrm{div}(G)\) |
|
\(\mathrm{div}(\alpha ~ F)\) |
\(\alpha~\mathrm{div}(F)\) |
|
\(\mathrm{div}(f ~ G)\) |
\(f~\mathrm{div}(G) + \mathrm{dot}(G, \mathrm{grad}(f))\) |
|
\(\mathrm{div}(\mathrm{cross}(F, G))\) |
\(-\mathrm{dot}(F, \mathrm{curl}(G)) + \mathrm{dot}(G, \mathrm{curl}(F))\) |
Evaluation of \(\mathrm{laplace}\) operator#
Rule ID |
symbolic expression |
evaluation |
---|---|---|
|
\(\mathrm{laplace}(f+g)\) |
\(\mathrm{laplace}(f) + \mathrm{laplace}(g)\) |
|
\(\mathrm{laplace}(\alpha ~ f)\) |
\(\alpha~\mathrm{laplace}(f)\) |
|
\(\mathrm{laplace}(f~g)\) |
\(f ~ \mathrm{laplace}(g) + g ~ \mathrm{laplace}(f) + 2 \mathrm{dot}(\mathrm{grad}(f), \mathrm{grad}(g))\) |
Evaluation of specific combination of operators#
Rule ID |
symbolic expression |
evaluation |
---|---|---|
|
\(\mathrm{curl}(\mathrm{grad}(f))\) |
\(0\) |
|
\(\mathrm{div}(\mathrm{curl}(F))\) |
\(0\) |
|
\(\mathrm{div}(\mathrm{cross}(\mathrm{grad}(F), \mathrm{grad}(G)))\) |
\(0\) |
|
\(\mathrm{curl}(\mathrm{curl}(F))\) |
\(\mathrm{grad}(\mathrm{div}(F)) - \mathrm{laplace}(F)\) |
|
\(\mathrm{curl}(f~\mathrm{grad}(g))\) |
\(\mathrm{cross}(\mathrm{grad}(f), \mathrm{grad}(g))\) |