# All Questions

1k views

### Search the neighborhood area along a line in an image

I am trying to search for the black areas along a line (the horizontal line shown below). Though it is straight in this picture, it could be of irregular shape in other cases. It seems that the ...
195 views

### How can one type a box with “x” marked?

In some text portion of my notebook, I would like to be write check boxes which are empty, check marked or "x" marked. The following commands work for the first two: ...
221 views

### Alternative to using global variables in functions?

Often times I find myself using unevaluated variables (i.e. they show up blue) as dummy variables in whatever I'm returning such that I can evaluate them as needed later on. A simple example is as ...
752 views

### Convenient methods to sum select rows (or cols) of a matrix? [duplicate]

What are some convenient methods to sum selected rows or columns in a matrix? This question Summing along rows or columns of a matrix only addresses how to sun entire rows or columns ie, by level. ...
373 views

### Is it possible to create a compiled function with some symbolic arguments?

I am trying to create a compiled function that takes in several arguments. However, some of the arguments contain symbolic entries and thus I get the following error message when executing the cell ...
202 views

### Trouble with Flatten[]

I made this function: f[g_] := Table[{ToExpression[ToString[x] <> ToString[n]], 1, 3}, {n, 1, g}] When I evaluate the function with some g (say 8), I'll ...
260 views

### How to blend some colors on a curve

I need to define a color gradient on a 3D curve, but I'm having some problems with this. Suppose we have a 3D curve defined as a parametric function of some real variable ...
237 views

### Autocomplete short symbol names in non-global context

Is it possible in v9 to autocomplete the short symbol names when one is operating in a context other than Global`? I.e. after evaluating the following: ...
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6k views

### Label points in plot with a text

I'm a newbie at Mathematica and I couldn't find how to label the maximum and the zero of a simple function in Plot with their names: ...
789 views

### Accessing list elements by name

First, a bit of a long introduction to my problem: I only have a few weeks of Mathematica experience. I am creating a mathematica application that calculates some material properties of steel based ...
300 views

### Plot an undefined function

When I plotted an undefined function, Mathematica also spends considerable time to process it. It returns a blank figure necessarily. What confuses me is where the ...
331 views

### Haiku Extractor

Inspired by the cool Tumblr Haiku Times that searches for accidental haiku in New York Times articles, I tried my hand at implementing such a search in Mathematica for my own text samples. I'm still ...
370 views

### How to capture Print output

How can I capture output from Print from a function which does not leave the printed object as its final output, (and which I do not wish to edit)? E.g. ...
114 views

### How does SocialMediaData determine vertex size

How does SocialMediaData determine the size of graph vertices, e.g. on what does the vertex size depend in, say, a Facebook friend network graph?
234 views

### Compile: Putting integers into a list

The first part below is already answered, but I've got another question which I think is closely related to this one, so I edited my question. First part: I started compiling in Mathematica a few ...
549 views

### Stop use of scientific notation when displaying FrameTicks

I have a dynamic graph which changes depending on the current selection from a drop down box. All selections from the drop down box give fine results except one. For the one selection it shows the ...
1k views

### Plotting multiple parametric functions with different intervals

I want to make a parametric plot like this: ParametricPlot[{{2 t, -10 t^2}, {t, 2 t}}, {t, 0, 2}] I have tried the following but it doesn't work: ...
41 views

### Does an equivalent of marks in vim exist for navigating notebooks quickly? [duplicate]

Is it possible in the Mathematica front-end to associate a keyboard shortcut with a cursor location in the notebook (kind of like marks in vim) so that one can return to them quickly later? (Just ...
182 views

### Can the elements of a list always be sorted into a canonical order?

As the title states - does a unique order exist for any Mathematica list to be sorted by the Sort[] function (or as returned by a function that treats lists as ...
112 views

### How to evaluate an integral

I am trying to evaluate this integral Integrate[(kx^2/2)*Sin[\[Lambda]x], x] from -pi/2(lamda) to pi/2(lamda) Everything there is a constant, and the only ...
1k views

### How to plot a 3D surface with a simple black and white style?

Mathematica has great plotting capabilities. However, sometimes what is needed is a very basic black and white plot without textures, lighting, glow and other complex features. So, here is my ...
158 views

### Using the mouse coordinates to index a matrix

I would like to "write" on to a matrix using the mouse. That is, I would like to use the integer value of Locator coordinates (p) to index a matrix. Then, if the mouse button is down, write a 1 in ...
1k views

### Plot 2D Vector function in 3D

I want to plot a 2D vector function such as $F(x,y) = (a(x,y),\,b(x,y))$ in a 3D graph so that the vectors are embedded in the xy plane. I tried to do the following: First I defined a piecewise ...
149 views

### How do I remove this awkward plane? [duplicate]

Using Plot3D, I tried to plot $x^3 + y^3+3xy=z$ ...
289 views

### Simplifying numerical expressions involving special functions

I've encountered the following problem. There is the identity (Legendre's relation) that the special functions EllipticK[x] and ...
1k views

### How do I obtain the enclosed area of this particular parametric plot?

I'm trying to find a way to obtain the enclosed area of this particular plot. Can someone show me how? ...
259 views

### Numerical Error with Large Matrices

I am writing a Finite Element Analysis program in Mathematica. The code involves handling a large matrix with large entries. I get an error when I try to use Mathematica's "LinearSolve" to solve a ...
693 views

### FullSimplify Over Reals Automatically

Frequently, Mathematica will produce some expression in a complicated form, with a number of unset variables. For me, it is rare that I would be interested in solutions that are generalized to both ...
1k views

### Plotting data points: Optimizing size and visuals

The following problem is one that may have showed up to you while plotting a large data collection. Suppose you have a data set of say 1 million points. ...
190 views

### Precision of rendered Rectangles in stiff-scale graphics

The attchd graphics called chromograms represent a set of discrete-state, continuous-time - ie, discrete-event signals, generated with Mathematica 9 on OSX with a Cinema display. • Top 2 rows are ...
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### How can I get a Button to evaluate an expression containing Get? [duplicate]

I have problems making Button evaluate an input like this one: Button["Load", Get["/Users/simonlausen/Desktop/Input/ex1.mx"]] ...
284 views

### NMinimize problem again

Following up my previous question which got great replies, I am now trying to do ...