# Questions tagged [vector-calculus]

Questions on dealing with vector calculus functions of Mathematica such as Grad, Div, Curl, Laplacian and their representations in various coordinate systems.

299 questions
Filter by
Sorted by
Tagged with
1 vote
145 views

### PlotLegends and VectorAnalysis is now obsolete on Mathematica v 12.0.0.0 Home edition [closed]

My code was working a few months ago. Now I receive the messages: ...
157 views

### Plotting list data of cross product of field vectors

I have some experimental data points of electric Ey(t, value) and magnetic field Hz(t, value). I am trying to calculate the ...
794 views

1 vote
78 views

### Derivative of quadratic form in NCAlgebra

I installed the NCAlgebra package in the hope that it contains enough rules for symbolic work with most branch-matrix expressions. ...
150 views

### Set of quadratic forms and linear algebra

I have a set of quadratic forms. $L_{1}=u_1^TJ_{1}u_1$ $L_{2}=u_2^TJ_{2}u_2$ $L_{3}=u_3^TJ_{3}u_3$ where $u_{i=1,2,3}$ - 3$\times$1 vector; where $J_{i=1,2,3}$ - 3$\times$3 matrix; I need to pack ...
207 views

### How do I find the unit vector in the direction of the minimal rate of change?

A ball falls on the surface $x^4 z+x^9 y^2+y^2 z^3=65$ at the point (-1,-3,2). How do I find a three-dimensional unit vector in the direction that the ball will begin to roll. I know that the ball ...
1 vote
125 views

### About composition of functions (I don't want to use a vector variable function)

f2[x_, y_] := x^2 + y^3; g[t_] := {t^2, 3*t+1} $g$ returns a list, but $f_2$ is a two variable function. So, we cannot compose these functions: ...
1 vote
145 views

### How to compute the divergence of a four-vector?

I have a quadri-vector which is given by u = {(E^(-φ0[r]))*(1 - ε δφ[t, r]), (E^(-φ0[r])) D[ε ξ[t, r], t], 0, 0} and a quantity n which is given by <...