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This is a list of some vector calculus formulae for working with common curvilinear coordinate systems.
Note that the operation arctan ( A B ) {\displaystyle \arctan \left({\frac {A}{B}}\right)} must be interpreted as the two-argument inverse tangent, atan2.
div A = lim V → 0 ∬ ∂ V A ⋅ d S ∭ V d V = [ A x ( x + d x ) − A x ( x ) ] d y d z + [ A y ( y + d y ) − A y ( y ) ] d x d z + [ A z ( z + d z ) − A z ( z ) ] d x d y d x d y d z = ∂ A x ∂ x + ∂ A y ∂ y + ∂ A z ∂ z {\displaystyle {\begin{aligned}\operatorname {div} \mathbf {A} &=\lim _{V\to 0}{\frac {\iint _{\partial V}\mathbf {A} \cdot d\mathbf {S} }{\iiint _{V}dV}}\\[1ex]&={\frac {\left[A_{x}(x{+}dx)-A_{x}(x)\right]dy\,dz+\left[A_{y}(y{+}dy)-A_{y}(y)\right]dx\,dz+\left[A_{z}(z{+}dz)-A_{z}(z)\right]dx\,dy}{dx\,dy\,dz}}\\&={\frac {\partial A_{x}}{\partial x}}+{\frac {\partial A_{y}}{\partial y}}+{\frac {\partial A_{z}}{\partial z}}\end{aligned}}}
( curl A ) x = lim S ⊥ x ^ → 0 ∫ ∂ S A ⋅ d ℓ ∬ S d S = [ A z ( y + d y ) − A z ( y ) ] d z − [ A y ( z + d z ) − A y ( z ) ] d y d y d z = ∂ A z ∂ y − ∂ A y ∂ z {\displaystyle {\begin{aligned}(\operatorname {curl} \mathbf {A} )_{x}&=\lim _{S^{\perp \mathbf {\hat {x}} }\to 0}{\frac {\int _{\partial S}\mathbf {A} \cdot d\mathbf {\ell } }{\iint _{S}dS}}\\[1ex]&={\frac {\left[A_{z}(y{+}dy)-A_{z}(y)\right]dz-\left[A_{y}(z{+}dz)-A_{y}(z)\right]dy}{dy\,dz}}\\&={\frac {\partial A_{z}}{\partial y}}-{\frac {\partial A_{y}}{\partial z}}\end{aligned}}}
The expressions for ( curl A ) y {\displaystyle (\operatorname {curl} \mathbf {A} )_{y}} and ( curl A ) z {\displaystyle (\operatorname {curl} \mathbf {A} )_{z}} are found in the same way.
div A = lim V → 0 ∬ ∂ V A ⋅ d S ∭ V d V = [ A ρ ( ρ + d ρ ) ( ρ + d ρ ) − A ρ ( ρ ) ρ ] d ϕ d z + [ A ϕ ( ϕ + d ϕ ) − A ϕ ( ϕ ) ] d ρ d z + [ A z ( z + d z ) − A z ( z ) ] d ρ ( ρ + d ρ / 2 ) d ϕ ρ d ϕ d ρ d z = 1 ρ ∂ ( ρ A ρ ) ∂ ρ + 1 ρ ∂ A ϕ ∂ ϕ + ∂ A z ∂ z {\displaystyle {\begin{aligned}\operatorname {div} \mathbf {A} &=\lim _{V\to 0}{\frac {\iint _{\partial V}\mathbf {A} \cdot d\mathbf {S} }{\iiint _{V}dV}}\\&={\frac {\left[A_{\rho }(\rho {+}d\rho )(\rho {+}d\rho )-A_{\rho }(\rho )\rho \right]d\phi \,dz+\left[A_{\phi }(\phi {+}d\phi )-A_{\phi }(\phi )\right]d\rho \,dz+\left[A_{z}(z{+}dz)-A_{z}(z)\right]d\rho (\rho {+}d\rho /2)\,d\phi }{\rho \,d\phi \,d\rho \,dz}}\\&={\frac {1}{\rho }}{\frac {\partial (\rho A_{\rho })}{\partial \rho }}+{\frac {1}{\rho }}{\frac {\partial A_{\phi }}{\partial \phi }}+{\frac {\partial A_{z}}{\partial z}}\end{aligned}}}
( curl A ) ρ = lim S ⊥ ρ ^ → 0 ∫ ∂ S A ⋅ d ℓ ∬ S d S = A ϕ ( z ) ( ρ + d ρ ) d ϕ − A ϕ ( z + d z ) ( ρ + d ρ ) d ϕ + A z ( ϕ + d ϕ ) d z − A z ( ϕ ) d z ( ρ + d ρ ) d ϕ d z = − ∂ A ϕ ∂ z + 1 ρ ∂ A z ∂ ϕ {\displaystyle {\begin{aligned}(\operatorname {curl} \mathbf {A} )_{\rho }&=\lim _{S^{\perp {\hat {\boldsymbol {\rho }}}}\to 0}{\frac {\int _{\partial S}\mathbf {A} \cdot d{\boldsymbol {\ell }}}{\iint _{S}dS}}\\[1ex]&={\frac {A_{\phi }(z)\left(\rho +d\rho \right)\,d\phi -A_{\phi }(z+dz)\left(\rho +d\rho \right)\,d\phi +A_{z}(\phi +d\phi )\,dz-A_{z}(\phi )\,dz}{\left(\rho +d\rho \right)\,d\phi \,dz}}\\[1ex]&=-{\frac {\partial A_{\phi }}{\partial z}}+{\frac {1}{\rho }}{\frac {\partial A_{z}}{\partial \phi }}\end{aligned}}}
( curl A ) ϕ = lim S ⊥ ϕ ^ → 0 ∫ ∂ S A ⋅ d ℓ ∬ S d S = A z ( ρ ) d z − A z ( ρ + d ρ ) d z + A ρ ( z + d z ) d ρ − A ρ ( z ) d ρ d ρ d z = − ∂ A z ∂ ρ + ∂ A ρ ∂ z {\displaystyle {\begin{aligned}(\operatorname {curl} \mathbf {A} )_{\phi }&=\lim _{S^{\perp {\boldsymbol {\hat {\phi }}}}\to 0}{\frac {\int _{\partial S}\mathbf {A} \cdot d{\boldsymbol {\ell }}}{\iint _{S}dS}}\\&={\frac {A_{z}(\rho )\,dz-A_{z}(\rho +d\rho )\,dz+A_{\rho }(z+dz)\,d\rho -A_{\rho }(z)\,d\rho }{d\rho \,dz}}\\&=-{\frac {\partial A_{z}}{\partial \rho }}+{\frac {\partial A_{\rho }}{\partial z}}\end{aligned}}}
Del in cylindrical and spherical coordinates AI simulator
(@Del in cylindrical and spherical coordinates_simulator)