4
votes
2answers
546 views

Using compiled function inside NMinimize

Consider this code: ...
4
votes
1answer
644 views

How to dequantify units in mathematica?

Is there a function which applied to a quantity returns its numerical value so I for instance can fill it into my Predictorfunction?
4
votes
3answers
618 views

Summation with constraints

I am trying to do the summation shown below, $\sum_{i_1=0}^{imax_1} \sum_{i_2=0}^{imax_2} \dots \sum_{i_k=0}^{imax_k} f(i_1,\dots,i_k)$ $k$ is a variable. Therefore $i$ and $imax$ are defined as ...
3
votes
1answer
79 views

Formatting All Appropriate Output as Desired Automatically

I want to output in MatrixForm whenever I have a list/vector/matrix, but I do not want to have to type out the command each time. How can I write one command at ...
3
votes
1answer
2k views

How to define custom operators

I am currently running Mathematica 8 and I would like to know how to define custom operators. Let's say I define an operator called $\times$ where: $$a\times b = a+a\cdot b+b$$ I also want to know ...
3
votes
2answers
2k views

How can I solve an equation with symbolic coefficients?

I want to try to solve the following a x^(17/6) - b x^2 - 1 == 0 where a and b are ...
3
votes
2answers
164 views

How to deal with the condition that a function own many options?

Assming that I have a function myFunc which has some options. ...
3
votes
2answers
1k views

Map a 3D plot into plane

I have a 3D plot like: ...
3
votes
1answer
5k views

Filtering Lists in Mathematica [duplicate]

Possible Duplicate: Select/Delete with Sublist elements? I need help in filtering long lists of x,y coordinates.Lets use the following list as an example: <...
3
votes
2answers
249 views

Key to get help about current function

I know you can hit F1 to pop up the documentation center, and then type the name of a function and search for it. I'd like to know if there's a key that just pops up the help page of the function ...
3
votes
2answers
1k views

Forecast Future Stock Prices - Brownian Motion - Again

excuse me, I think I have here a technical problem with Mathematica yesterday I posted the question with the title: Forecast Future Stock Prices - Brownian Motion I am still not very experienced but ...
3
votes
1answer
257 views

Export ContourPlot as DXF

I'm having some trouble exporting a ContourPlot as a .DXF (to be used in AutoCAD). My code is: ...
3
votes
2answers
188 views

Importing CSV with multiline text fields

Here is a valid CSV: a1,b1,c1,d1,"e1 e1 e1" a2,b2,"c2 c2 c2",d2,e2 It has two rows and five columns, and contains two fields with embedded CRLF. (See the CSV ...
3
votes
2answers
941 views

All possible solutions to the Matrix Equation (free variables appearing)

I am attempting to solve a system of linear equations using LinearSolve[] . In my case, the number of unknowns are more than constraints. I learnt that LinearSolve ...
3
votes
3answers
1k views

Plotting heat equation in a Manipulate expression

I have a 2D heat equation $u_t = \alpha (u_{xx} + u_{yy})$ with conditions: $u(x, y, 0) = 300$, $u_y(x, 0, t) = \mu_1(x)$, $u_y(x, 1, t) = \mu_2(x)$, $u(0, y, t) = \mu_3(y)$, $u(1, y, t) = \mu_4(y)$,...
3
votes
1answer
235 views

Convert C program using mathlink to WSTP

I have been using heavily a custom frontend to mathematica based on mathlink. I derived it from http://library.wolfram.com/infocenter/Demos/174/frontend.c?file_id=4692 . I just learned that mathlink ...
2
votes
1answer
222 views

Importation multiple dcm images [duplicate]

I'm extremely new to Mathematica. I want to import 201 .dcm (DICOM) files into Mathematica 9. Is there a way to do this which doesn't require my doing it an image at a time? My ultimate need to is to ...
2
votes
2answers
533 views

EdgeRenderingFunction question

Bug introduced in 9.0 and fixed in 10.0.0 (Edit 1 : I added this paragraph after the original post, for context) Some context for this question can be found in another post (http://mathematica....
2
votes
3answers
3k views

How to find intersection points of lines?

Considering I have three functions f1 = -x + 1; f2 = x - 1; f3 = x + 3; How can I find the intersection points of this functions? Thanks. This didn't work <...
2
votes
0answers
991 views

ParametricNDSolveValue or NDSolve + fitting

I have been trying to find the value for the parameter kestim that yields the best fit of a model to some data points. datac has ...
2
votes
1answer
52 views

How can you delete a list of vertices from a GridGraph?

Given a grid graph: and delete the vertices {3, 4, 5, 11, 14, 15, 16, 17, 18, 19, 21, 23, 26, 27, 30} and preserve the structure. There is the ...
2
votes
1answer
89 views

DeleteVertex in Kpartite graph

How can i make K7,2 graph and how can i delete 2 vertex? Btw, i need to use package -> Combinatorica`; I tried this: ...
2
votes
4answers
214 views

How to place more than one ChartLabel in a BarChart

I have the following data: ...
2
votes
2answers
241 views

Attempting to use NDSolve to plot harmonic oscillator solutions

NDSolve[{ (-y''[r]/1880) + (470 (0.04077)^2 r^2 - 48 + 1/(1880 r^2)) y[r] == 0, y[0] = 0, y'[0] = 0}, y, {r, -4, 4}] I use this but get errors and am ...
2
votes
1answer
110 views

Entering an differential equation in a Manipulate box

Does anyone have an example of a Manipulate demonstration where the user can type into a box the differential equation, time interval, initial condition, and the result is plotted? This possible in ...
2
votes
1answer
509 views

Finding the eigenfunctions of one and two dimensional Harmonic Oscillator

(Edited) For finding the ground state wave function of: $ H\psi(x) = (-1/2)d^2\psi(x)/dx^2 + (1/2)x^2\psi(x) = E \psi(x)$ I have written: ...
2
votes
1answer
1k views

Adding an image background to a graph that uses vertexposition

Hello Mathematica stackexchange community! I need your help on a research project. I'm looking to create a graph g with vertices in specifies places and then use an image I have as the background of ...
2
votes
2answers
606 views

How to define a vector with automatically added symbolic elements with subscripts

I want to define a vector lets say k containing elements Symbolize[Subscript[k, 1]], k2, k3 ... etc. When I define lets say k4 . I want the symbol automatically added to vector k. Something like ...
2
votes
1answer
879 views

Using triangulation

I have been presented with 3 known points and the power densities at those points. I need to use those points to find the location of the actual antenna which is generating the signals. Power ...
2
votes
2answers
982 views

NDSolve problems of convergence

I have a big function that I have to maximize, so I have to evaluate some equation with thousands of different values of the parameter. But the FindMaximum returns me many errors. I have traced the ...
2
votes
0answers
115 views

Incompability between v5-6 and v10 with Graphs and Oriented Graphs pkgs?

Notice that "although the v6 Packages are available at the link in the answer above they are not fully compatible with v10". The errors 1, 2 and 3 in Mathematica 10 student edition may be due to ...
2
votes
1answer
297 views

Extracting information from list

I have a huge list that looks like this: ...
1
vote
2answers
895 views

Using Array Elements as Function Arguments

Suppose I have an array p = {a,b,c,d} and a function f that takes a variable number of arguments. I want to evaluate ...
0
votes
1answer
4k views

Stategies to avoid NIntegrate::slwcon error

I am trying to numerically evaluate an integral whose integrand depends on two parameters, say $(a,b)$ and when $b\gg 1$ I suspect (although it's not guaranteed) that the integrand is very small. Thus ...
29
votes
0answers
662 views

Changing FrontEnd automatic scrolling in version 8

In Mathematica versions < 8, the FrontEnd has a very intelligent behavior: On evaluation, it by default automatically scrolls down the Notebook window to the last printed Output cell but also ...
20
votes
4answers
423 views

Unexpected result {“.a”, “co”, “.m”} from Sort[{“.m”, “.a”, “co”}]

I came across the following situation: Evaluating Sort[{".m", ".a", "co"}] Results in {".a", "co", ".m"} I wondering: ...
20
votes
2answers
300 views

Incorrect Timing of Total

For demonstrating how fast C-compiled functions can be, in one of my courses I use the following function for finding the sum of a list of reals: ...
18
votes
2answers
6k views

Plotting vectors originating from the origin in 3D

I have an array of data with 3D elements. Ex: x = {{1,2,3}, {3,4,5}, {5,6,7}}. I want to show this data in 3 dimensions, such that each point in the space is shown ...
18
votes
5answers
2k views

Insphere for Irregular Tetrahedron

I am looking for existing Mathematica code to compute the unique sphere inscribed inside an irregular tetrahedron. I can write it myself, but I would love to find that someone already performed this ...
18
votes
4answers
612 views

How do I introduce a new variable in a trigonometric equation?

I have the trigonometric equation \begin{equation*} \sin^8 x + 2\cos^8 x -\dfrac{1}{2}\cos^2 2x + 4\sin^2 x= 0. \end{equation*} By putting $t = \cos 2x$, I have \begin{equation*} \dfrac{3}{16} t^4+ \...
17
votes
0answers
309 views

RegionPlot returning a number

Bug introduced in 10.0 and persisting through 10.4 or later I had updated my mathematica to version 10 few days ago. And I had been shocked by the following fact: ...
16
votes
2answers
272 views

A bug in Commonest in version 10

Bug introduced in 10.0.0 and fixed in 10.0.2 m_goldberg demonstrated that in Mathematica 10 Commonest does not behave as the documentation indicates that it will....
15
votes
2answers
465 views

Why do NumberForm and Round apparently use different tie-breaking methods?

When rounding numbers (for example, rounding a real number to the nearest integer), the "round to nearest" rule is usually used. For example, 1.4 is rounded down to 1 and 1.6 is rounded up to 2. ...
15
votes
1answer
458 views

Why do Arrowheads interfere with ImagePadding?

Bug still present in version 10 under Windows. In a recent posting, Belisarius solved a problem related to the display of arrows on the x and y axes by setting ...
15
votes
1answer
462 views

Strange behaviour of Reduce for Mod[x,1]

For every integer $x$ the equation Mod[x, 1] == 0 holds. While Simplify[Mod[x, 1] == 0, Element[x,Integers]] gives ...
15
votes
3answers
326 views

Why does Mathematica simplify $x/x\to1$?

If I enter x/x, I get 1. Such behavior leads to this: Simplify[D[Sqrt[x^2], x, x]] 0 ...
15
votes
3answers
957 views

How to remove accents from text?

I would like to know how I can remove accents from a string. For example, how can I transform "string test áéíóú" into ...
14
votes
2answers
379 views

FindInstance returns Indeterminate in version 9, but not in 8

Bug introduced in 9.0 and fixed in 10.0.0 Here is a trivial system of equations in three unknowns for which FindInstance obtains a solution: ...
14
votes
3answers
650 views

How would I return a random Mathematica command?

I'm doing some metaprogramming. How would I make a Mathematica function that returns a random Mathematica command? Is there a list of command names that I could use ...

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