Tensor Products with Derivatives in Mathematica
- To: mathgroup at smc.vnet.net
- Subject: [mg121921] Tensor Products with Derivatives in Mathematica
- From: Thomas Markovich <thomasmarkovich at gmail.com>
- Date: Thu, 6 Oct 2011 04:26:05 -0400 (EDT)
- Delivered-to: l-mathgroup@mail-archive0.wolfram.com
Hi, I would like to take the tensor product of two gradient operators so that I can construct a matrix "derivative." This is to say that I want to do the following \begin{pmatrix} \partial_x \\ \partial_y \\ \partial_z \end{pmatrix} \begin{pmatrix} \partial_x & \partial_y & \partial_z \end{pmatrix} = \begin{pmatrix} \partial^2_{x,x} & \partial^2_{x,y} & \partial^2_{x,z} \\ \partial^2_{y,x} & \partial^2_{y,y} & \partial^2_{y,z} \\ \partial^2_{z,x} &\partial^2_{z,y} & \partial^2_{z,z} \end{pmatrix} and I have tried to do Qt = ( { {(=E2=80=98=E2=84=A2 =CB=9CSubscriptBox[=E2=84=A2=E2=88=82, =E2=84=A2x]# + W11), (=E2=80=98=E2=84=A2 =CB=9CSubscriptBox[=E2=84=A2=E2=88=82, =E2=84=A2y]# + W12)} } ) &; Q = ( { {(=E2=80=98=E2=84=A2 =CB=9CSubscriptBox[=E2=84=A2=E2=88=82, =E2=84=A2x]# + W11)}, {(=E2=80=98=E2=84=A2 =CB=9CSubscriptBox[=E2=84=A2=E2=88=82, =E2=84=A2y]# + W12)} } ) &; Qt@Q But this appears not to work. Any ideas? Thomas