# All Questions

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### 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, ...
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 ...
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 ...
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 ...
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 ...
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 ...
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 ...
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 ...
36 views

### Returns vs. Volume

Why do the "Return" and "Volume" outputs of FinancialData differ? Consider the following ...
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 ...
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 ...
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 ...
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 ...
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 ...
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 ...
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 ...
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### 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 ...
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: ...
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 ...
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: ...
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.
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 ...
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 ...
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 ...
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 ...
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: ...
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: ...
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}}; ...
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) ...
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 ...
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 ...
42 views

### Strange behavior of function (memory leaks)

I have some funtion: ...
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) ...
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 ...
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 : ...
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 ...
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: ...
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 ...
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 ...
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} ...
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: ...
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.
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 ...
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 ...
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: ...
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 ...
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?