Linked Questions

3
votes
0answers
232 views

Measuring Temp on a cubical using heat equation with Neumann and Dirichlet boundary conditions

I'm trying to solve 3D heat equation to understand how the temperature varies with time on cubical. i have mixed boundary conditions: Dirichlet on the bottom surface (constant Temp) Neumann on all the ...
1
vote
0answers
110 views

Pattern for a function of say 2 variables [closed]

How can I specify a pattern for an expression f for which say f[x,y] returns a value, ie is defined as a function taking two ...
2
votes
0answers
142 views

NDeigensystem returns error due to mesh discretization when calculating vibrations of a cantilever

There was an transcription error in the code I provided in a previous post: https://mathematica.stackexchange.com/questions/105713/ndeigensystem-returns-complex-non-hermitian-error-for-the-...
1
vote
2answers
129 views

I want to plot a list of points with specified t and x[t] coordinates [closed]

I have this code: ...
5
votes
2answers
6k views

How do I plot a solution of a differential equation?

I am having trouble generating a plot for a solution to my differential equations. I always end up with just blank axes. ...
1
vote
0answers
135 views

Solving a set of trigonometric equations [closed]

I've been trying to solve the following equations in order to plot Subscript[θ, 41] with respect to Subscript[θ, 2] from 0 to ...
0
votes
0answers
60 views

What makes items with head `Function` different?

I apologize beforehand for the muddleheadedness of this question. It reflects the fact that I'm trying to interpret outward "behaviors" of Mathematica expressions without having any understanding of ...
6
votes
1answer
627 views

What does it mean when a function is defined with two pairs of brackets

I have noticed a function defined as such: f[x_][y_] := expr; How is the argument y in 2nd pair of brackets being used? What is the difference from defining a ...
2
votes
1answer
120 views

Sum of operations involving an arbitrary number of 2D vectors

I need to define an equation stating that the sum of n operations involving n 2D vectors and ...
7
votes
4answers
276 views

Iteration of functions

I'm trying to define a function f, such that f[a_]:=a; f[f[a__]]:=f[a]; Then, I tried to evaluate f[x,y]. Since ...
7
votes
1answer
200 views

Graphics Function Definition Style (Using SubValues vs. DownValues)

I am going through some of the items in "Modern Differential Geometry of Curves and Surfaces with Mathematica, Third Edition". An example of the style used by these authors is: ...
1
vote
1answer
384 views

Create a function with Dt[x] as a variable

I have a function (for example F[x_]:=Cos[x]). I want to define a function like Fdot[x_,xdot_]:=Dt[F[x]] where xdot represents Dt[x]. For example, to define Fdot one might naivley try Fdot[x_,Dt[...
5
votes
2answers
616 views

Assignments in ParallelDo when using indexed variables

For convenience I use an indexed variables syntax to hold results of long computations for different integer parameters: ...
2
votes
1answer
794 views

Partial derivative of defined function with vector input

Background: Have written a formula for the refractive index for a glass slab (n) that depends on the variables t,a and d. Now I want to calculate for example some sort of error and I'll be needing to ...

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