2
votes
0answers
45 views

Implementation of the Vector Autoregressive Model

I need to code/write a Vector Autoregressive Model VAR(p) as a function of the parameters. There is no estimation, nor Data involved, this is a "population" exercise: Assume X and Y are univariate, ...
8
votes
2answers
83 views

Why isn't Lookup treated like other symbols?

With Mathematica 10, I wanted to overload Lookup using TagSetDelayed, but it doesn't work. For instance, if I define two objects ...
6
votes
3answers
78 views

How to combine one or more rotated graphics objects?

I wish to produce an image with more than one composite graphics objects which have been modified using Rotate. I feel this should not be difficult, but haven't yet found a solution. A simple example ...
3
votes
5answers
99 views

Algebraic expressions on pure functions

I would like to know how to perform algebraic operations with pure functions. Simple version: Here's a silly toy model: I want to transform the algebraic expression Sin*Cos into the function ...
3
votes
1answer
124 views

Issue in ParallelTable after evaluating another function using NDSolve and FindRoot. What is wrong with this inverse?

I am trying to find the inverse of a function which is defined through NDSolve and NIntegrate. The question is pretty similar ...
0
votes
0answers
10 views

Customizing display of partial differential equations

I am manipulating partial differential equations symbolically, and would like to get the easily readable form $\rho \frac{\partial v}{\partial t}$, leaving variables implicit. Based on suggestions ...
10
votes
6answers
622 views

Will Version 9 functions all work in Version 10?

Having developed a substantial code base in Mathematica 9, leads me to ask these important questions prior to downloading and installing Mathematica 10. Will any Mathematica functions from the ...
3
votes
3answers
85 views

Text with subscript is automatically Italic

I am creating a figure for a document using Graphics in which there is Text with some variables and again those same variables ...
1
vote
1answer
36 views

Returns vs. Volume

Why do the "Return" and "Volume" outputs of FinancialData differ? Consider the following ...
0
votes
2answers
101 views

Integral converging in M9 but not in M10

Summary: I have a notebook. It used to evaluate fine in Mathematica 9. I upgraded to 10 and without doing any modification at all to the notebook, an integral stopped converging. I even tried after ...
2
votes
0answers
40 views

Passing a variable messages list to Quiet

I'm trying to build a Verbose option into some code but I'm having trouble passing to a Quiet statement a variable list of which messages I want to suppress. My ...
3
votes
2answers
46 views

How to define a nestable Baseform function, BaseForm output becomes BaseForm input

Mathematica won't change a number's BaseForm recursively: 63969 // BaseForm[#, 16] & // BaseForm[#, 8] & // BaseForm[#, 2] & Well, I inspected former ...
0
votes
2answers
84 views

Find Root Iteration

I have an iterative sum from $k=0$ to $k=n$ where the resulting sum is a polynomial of degree $n$. I want to find the numerical root of this polynomial using FindRoot, starting from $x_0$ where the ...
13
votes
5answers
253 views

Mismatch between numerical and analytic evaluation of an integral

I evaluated the following integral NIntegrate[Sqrt[r] Abs[Cos[(k + 1/2) Pi r]], {r, 0, 1}] getting as a result 0.413232 for ...
3
votes
1answer
220 views

InstallR on OS X with external R installation

How do I InstallR on OS X to use my already installed and configured R? Simply using ...
4
votes
3answers
99 views

Using Mouseover to change the appearance of a button without writing the button specification twice

When I code in Mathematica, I often find myself having to repeat large chunks of code for a function to work. The latest example of this is a color changing button that prints when clicked, code shown ...
1
vote
1answer
32 views

Appending to $Assumptions -First AppendTo fails [on hold]

I need to use lots of assumptions in my code. Therefore I put them into the $Assumptions variable. When I do it like this, all is well: ...
5
votes
2answers
104 views

Example of Integrate applying a numerical evaluation N

Here is a minimal example: Integrate[(a[1] + x)^2, {x, 1., 2.}] 2.33333 + 3. a[1.] + 1. a[1.]^2 The problem is that ...
3
votes
1answer
136 views

Using NSolve in the complex plane

I am trying to find numerical values for $\Im\ e^{\frac{1}{2} +i\ y} = \Im\ \zeta(\frac{1}{2} +i\ y)$ for a given range. I have tried: ...
2
votes
1answer
28 views

Installing R packages using RLink on Mac OS X

Is there any updates regarding installing CRAN packages via RLink in Mathematica 10 on Mac OS X? Or are we still stuck with the base R package and that's it? I was able to point to my R distribution ...
2
votes
1answer
67 views

Numerical evaluation of ChebyshevT

When I evaluate the following Chebyshev series of the first kind in two different ways, I get two very different results: ...
10
votes
4answers
724 views

How to make a depth map from a 3D model?

Given a 3D .obj model, for example a rabbit. How can we make a depth map out of it? Any idea or help would be much appreciated.
4
votes
2answers
50 views

Laplace: from differential equation to transfer function

First at all, this is trictly related to my own question: How to transform transfer functions into differential equations? How can I transfer my differential equation into a transfer function? For ...
5
votes
7answers
259 views

Choosing $n$ equidistant points on a circle with given radius and center

I would like to have a function circle which takes two inputs: a tuple {x,y} and a real number ...
14
votes
6answers
365 views

How to understand the usage of Inner and Outer figuratively?

Description: In Mathematica the functions like Thread, Inner, Outer etc. are very important ...
20
votes
2answers
419 views

Why is Query so much slower than Part?

Time for another of these(1),(2) as yet another new-in-10 function appears to have poor performance compared to older alternatives. This time: Query appears to be ...
1
vote
0answers
38 views

V10 interface problems

Has anyone noticed the following? Sometimes when I bring up the Help->Wolfram Documentation there is no text field to type into. When I bring up Find and Replace there are two text fields for Find: ...
5
votes
0answers
85 views
+100

Slow work of SQLInsert with SQLite

I want to store my data in SQLite database, but writing large numbers of data its too slow. For example: ...
3
votes
3answers
117 views

Split matrix by all-zero columns

Below is my input: mat = {{0, 0, 0, 0, 0, 1}, {1, 0, 0, 1, 0, 1}, {0, 1, 0, 0, 0, 0}, {0, 0, 0, 0, 0, 1}, {1, 1, 0, 1, 0, 0}, {0, 0, 0, 1, 0, 1}}; ...
5
votes
3answers
153 views

Solving $L=\frac{3}{2} \sqrt{4 \pi ^2 A^2+W^2}-\frac{\sqrt{5 W \sqrt{4 \pi ^2 A^2+W^2}+6 \pi ^2 A^2+3 W^2}}{\sqrt{2}}+\frac{3 W}{2}$ for $W$

When I solve the aforementioned equation for $W$ or $A$ on Mathematica I get a long and ugly equation in return, namely one of the solutions for $W$ is: (attempt to read at your own health) ...
4
votes
1answer
81 views

Avoid writing explicit form of operator

I would like to evaluate the following (simplified) expression with Mathematica : $\frac{\delta}{\delta J} \exp[(J(x)+K(x)) \Delta (J(x)+K(x))]$ where $\Delta$ is a differential operator independent ...
2
votes
0answers
66 views

How do I write “such that” in mathematica?

I have a mathematical statement as follows : Tri := {(t1,t2): t1,t2>=0,t1+t2<=1} How can I tell Mathematica that I need to define vectors (t1,t2) 'such ...
0
votes
0answers
42 views
2
votes
0answers
35 views

Wavelet expansion of given function (as opposed to DWT of given data)

To illustrate, say I take the following function (the reason for the square root will be apparent soon) ...
1
vote
1answer
142 views

How to apply a tensor to a list of arguments

The problem I have is the following: Let C be a list of coordinates, say, C = {x1, x2, ..., xn} and ...
2
votes
2answers
130 views

How to get the current index during a Scan iteration?

Is there a special keyword to get the current index in Scan ? For example, let say I have the following code : ...
4
votes
2answers
150 views

Density plot of city data

I try to solve a bit tricky problem. I want define line (or vector) between some geographical points with weights (for example how many transactions has been done between these cities). I tried this ...
3
votes
1answer
91 views

Boundaries of graphical objects not displayed correctly

I have encountered two situations where Mathematica 10 is mishandling the outer pixels of plainly simple objects. I input this: ...
11
votes
1answer
323 views

How to write plain Greek in a text cell

If I create a text cell and type some greek text, most of the symbols are italics as if the cell had an Input style. It doesn't happen with latin characters. I recollect that it is impossible to fix ...
6
votes
2answers
155 views

Account for powers of 0 and 1 when defining function

I have a function that I am defining as (assume m,n,a,b are non-negative integers): myfcn[x_^m_ p_^n_, x_^a_ p_^b_] := basefcn[m, n, a, b]; and then extending to ...
6
votes
2answers
323 views

Mapping data on Archimedes' spiral

I would like to map my data on Archimedes' spiral and preserve the distance between points on the curve. The test data consists of 20 evenly spaced {x,y} ...
2
votes
0answers
64 views

Result of symbolic integration changed drastically by making assumptions

I would like to know the underlying reason for different outcomes for the two integration operation below. One of them includes a few assumptions, otherwise both have the same integrand: ...
0
votes
0answers
12 views

How can I calculate matrix differentiation? [migrated]

I am studying about the Matrix Differentiation. I don't know if this red box differential metric, which is how it is calculated.
7
votes
0answers
125 views

Proving the hairy ball theorem using xAct

I would to formally prove the hairy ball theorem in Mathematica, initially just for the $S^2$, and then see about generalizing. An approach I thought about to use the xAct package to define $S^2$ and ...
6
votes
1answer
88 views

How to sort the functions in a Package?

Once a Package like abc` has been installed, we can use "?abc`*" to scan all the functions defined in this Package. Now I ...
27
votes
2answers
1k views

How can I use the Klingon alphabet symbols?

Note: This functionality is presently missing. See: How to add named characters to Mathematica 10? Mathematica apparently supports the Klingon alphabet: ...
7
votes
1answer
66 views

Possible Bug in ProbitModelFit when used in a Dataset

Since upgrading to Mathematica 10 on Mac OSX I have come across a number of instances of this error, which occurs using Probit and Logit model fit. A bit of googling show this is something to do ...
15
votes
4answers
691 views

How to determine the convex hull of some text?

How can I get the co-ordinates of the convex hull of a piece of Text?
4
votes
2answers
184 views

Coordinate extraction and manipulating graphs as graphics objects

Consider the image below: GraphData[{"Wheel", 7}] Is it possible in Mathematica to lay several of these Graph along each ...
5
votes
2answers
175 views

Converting a string into a nested list of strings

The following string can be converted easily into a list with ToExpression ...

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