# All Questions

46 views

### Correct definition of a function to be passed to Nintegrate [duplicate]

If I type the following code ...
244 views

### ToExpression processing errors

Is their a way to get a more comprehensive return value when running ToExpression? For example when I run ...
93 views

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102 views

### Why doesn't Rationalize work for 0. in Interval?

Same motivation as this q. Why doesn't Rationalize work for 0.? Interval[{0., 1.}] // Map[Rationalize, #, {2}] & ...
123 views

### Simplify oversimplifies. What to do about it?

According to Mathematica 10: $$Simplify[\frac{\frac{1}{t^2}-1}{(t+\frac{1}{t})^2}]==\frac{1-t^2}{(1+t^2)^2}$$ However, the first equation does not tolerate $t=0$ because of a division by zero, but ...
65 views

### Trouble solving a system of partial differential equations [closed]

I am trying to solve a system of linear PDEs analytically and I dont get the answer. I am new to this tool, appreciate your help ...
70 views

### How to repeatly use random number generator in optimization problem

I am looking to run the optimization problem. I already finish my optimization code as below. ...
273 views

### How to use Feynman Slash notation?

How can I use Feynman slash notation, e.g., $\require{cancel} \cancel{A}$, in Mathematica? I've seen some answer from 2008 which doesn't seem to work well in Mathematica 10. I'd like this to be part ...
81 views

### What is Mathematica's comment-to-line-end token? [duplicate]

How can I make a full line of code into a comment by typing a single character inserted at start of the line? In other programming languages I can use characters such as ! , # and language processor ...
21 views

### Plotting a dispersion curve with complex wavevectors [duplicate]

I want to reproduce a dispersion curve from P. Zou's thesis found here: http://www.ipd.anl.gov/anlpubs/2001/06/39620.pdf on Pg. 31, Eq. 2.13. The problem is, the code below only gives values for the ...
95 views

### Orthogonalization is not commutative!

I get stuck into a problem: I am going to produce orthogonalized eigenvectors of a matrix and in any iteration. I shortened my question in the bellow line: Why do we face to different results of ...
145 views

### Select largest number using pattern

I have the following expression: myExpr=R[C[2],B].(II+R[C[3],C[2]].(II+R[C[4],C[3]])) I need to create a pattern which would replace the ...
80 views

### Easy way to solve a matrix equation for a matrix?

I have two sets of $10\times 10$ matrices $M1,M2,M3,M4,M5$ and $N1,N2,N3,N4,N5$ and I want to solve a set of equations for these matrices ...
41 views

### Working with Piecewise functions - Hexsplines

I'm trying to use the convolution definition of hexsplines, that is, a hexspline is the convolution of the indicator function of a hexagon (of sidelength 1 and centre $(0,0)$ ) with itself. I'm ...
66 views

### Mathematica package for explicit matrix representations of group generators?

While there are several packages that are capable of working with weights and roots (for example LieArt), I couldn't find any package that spits out explicit matrices for the generators, for example ...
88 views

### ListContourPlot3D drops data

I've generated an array of datapoints depending on three Variables and need to plot them in a comprehensive way. Easier than dividing the data into subplots of fixed variables, ...
241 views

### Extrema of a function of three variables

To identify and classify the critical points of the function $f(x,y,z)=x^3+xz^2-3x^2+y^2+2z^2$, I used the Hessian matrix method. ...
142 views

### Run mathematica scripts without initializing the kernel every time

There are two duplicate's of this question that seem to only work on linux/osx currently. So how can I viably run mathematica scripts without spawning a new session each time from command prompt? I ...
56 views

### Using Get function to return a specific expression

I am trying to use Getto import data saved as a .nb document. The problem is Getevaluates all expressions but only returns the ...
92 views

### Spurious infinite limit of integration message in NIntegrate

Bug introduced in 7.0 and persisting through 10.2 NIntegrate returns an error complaining that ComplexInfinity is an invalid ...
369 views

### Find all synonyms of word X that rhyme with word Y

Given two words x and y, I'd like to find the set of all words that rhyme with x and are synonymous with y. Is this possible with WordData or ...
164 views

### Different Set Semantics - Why is assoc[“a”] =. different from assoc[[“a”]] =.?

Accessing parts of an Association can be done either using Part or the [] extraction ...
102 views

### JSON Expandable/Collapsible Fields with OpenerView

When you have a deeply nested hierarchical JSON structure, tools like JSON Editor Online help a lot to get an overview of the structured data at various levels. In this way you control the ...
50 views

### Adding up a list of subscripted elements [closed]

I have a list of entries with subscripts. I want to add just the entries. How can I do that in the presence of subscripts? For example: list = {1a, 2b, 3c} And ...
71 views

### Choosing appropriate WorkingPrecision when solving numerical system of equations

Consider a linear system of equations, which is conveniently written as A.x=y. The matrix A has dimensions ...
123 views

### Reading from a file: complex number with small imaginary part

I'm trying to read a matrix from the next file: 1+1e-18i 24 42 23.43e-23i using u=Import["file.dat","Table"]; and then find, ...
74 views

### Exporting a Large Graphic Output Uncrops the Image

I want to export an image exactly as it is shown in the notebook, but when I specify a high image resolution, the image saved to disk does not match what is shown in the notebook (the image saved ...
93 views

### How to compare and remove x-coordinates (and the associated y-coordinates) that are less than previous x-coordinates?

I am using Mathematica version 9.0 and am trying to compare and remove x-coordinates, and the associated y-coordinate, that are less than previous x-coordinates. Below is an example using sample data. ...
89 views

### Adding a fading color only to 3D curves going outside a cylinder

I'm having a problem with color shades on multi curves drawn with the Mathematica 7.0 code below. All the curves with both their endpoints inside the unit cylinder (green circle on the picture below) ...
74 views

### Simplest use of transpose given a vector and a matrix [closed]

Suppose that I have: x = {1, 1}/Norm[{1, 1}]; A = {{1, 2}, {2, 1}}; What is the simplest way of calculating $x^T A\ x$? And are there symbols on any of the ...
106 views

### Evaluating Real and Imaginary parts in a dispersion equation via ContourPlot [closed]

I want to reproduce a dispersion curve from P. Zou's thesis found here: http://www.ipd.anl.gov/anlpubs/2001/06/39620.pdf on Pg. 31, Eq. 2.13. The problem is, the code below only gives values for the ...
59 views

### Integrate complains about incompatible quantities in integration limits

When I run the following code, Integrate throws ...
119 views

### Removing the background color from BarChart3D plot

I'm trying to make a 3D bar chart plot with transparent faces on the sides, but for some reason it's very hard to remove them (or to make them transparent at least). I tried looking through the ...
44 views

### Mesh-Warping image from 3DS

Id there a way to warp an image using a mesh (plane with 14x8 cells) I have created and imported from 3d-studio? The reason for this is to warp a UV texture so I can look up quickly for distorted ...
40 views

### Call Remote Kernel from NETLink

Is it possible to run a remote kernel from NETLink in some way as suggested by the second method below: DoRemoteMathCommand? ...
45 views

### Deleting duplicates of plus or minus symbolic quantities from a list [closed]

Let's say I have a list l = {a + bc - d, -a - bc + d, a + b};. Now I want to apply DeleteDuplicates[l, crit] to this list, such ...
111 views

### Interpreting Results of Repeated Measures - Shift calculation in plots

What would be a more accurate method to calculate the shift in waveform (waveform drift) from a collection of 20 or more data plots. Current method, Plot all using Show and see if there is some ...
52 views

### How to simultaneously extract contourvalues and contourline?

Given a contour plot, plt=ContourPlot[Sin[x y],{x,-1,1},{y,-1,1}] I can extract the values of the contour lines using, ...
96 views

I would like to add a fading color to all the 3D lines I'm drawing with the code below, but I'm having difficulties with implementing the idea. The curves are starting on a unit sphere, and extend in ...
124 views

### Piping StandardForm from within GUI

I am working on a GUI project where I need to pipe a string I constructed in Mathematica into an external program. For example ...
72 views

### How to get a difference of two contour integrals depending on integer parameter?

I have two following functions: ...
99 views

### Simple minimization not evaluating

I tried to solve a rather simple optimization problem, which Mathematica apparently cannot handle. A minimal example is the following: ...
229 views

### How to use WikiMapia as GeoServer?

I wish to use the Wikimapia map as background in GeoGraphics. According to the Wikimapia Docs, Wikimapia's URL is encoded as follows: An example Wikimapia URL ...
203 views

### Turning an expression into a function inside another function

Say I have an expression g=Sin[q]; It is easy to turn it into a function, and to perform manipulations on this function (this and variants of this were discussed ...
134 views

### An error disappears?

I needed to define a table of functions. And I did it like this: ...
26 views

### Function assigning loop misses a beat [duplicate]

Ive come across this in managing a table, but is seems to be reproducible in simpler forms. I simply want to iterate a defined function for various values and then work with those at a later time. ...
148 views

### Problems with StateSpaceModel in v10.2

Bug introduced in 10.0.2 and fixed in 10.3 I don't know if this is a bug, or if just something changed I can't figure out. Take the following examples: ...
113 views

### How to use ForAll to prove things about functions?

Suppose I first declare: \$Assumptions = ForAll[{a,b}, b > a, f[b] > f[a]] I (wrongly, as it turns out) assume that that this would cause ...