# All Questions

594 views

### The longest run of at most k different elements in a list

I have a long list with ca. 500K elements. The list contains about 10K different elements. For simplicity let’s assume the list is of the following form: ...
245 views

### Can GPU (CUDA) speed up LinearSolve?

Is there a way to use GPU (CUDA) to speed up LinearSolve?
293 views

### Distinguishing left from right adjacent triangles in triangle mesh [closed]

What I'm trying to do: I'm trying to create a path-drawing function which will produce a path like the one I-P in the diagram below. The way this path was generated requires me to swap between the ...
613 views

### Extracting intensity from an image

Suppose I have an image sampleOriginal = Import["...mySample.png"] I then convert it to Grayscale colorspace ...
149 views

### LinearModelFit - Number of unique basis functions & Invalid variable errors

I'm having trouble with a simple linear fit model. Here is my code ...
3k views

### How to calculate extremely large exponential

I would like to calculate the following nested exponential: $$\Large{e^{e^{10^{72}}}}$$ In case that might be hard to read, in Mathematica functional notation it is: ...
199 views

### How can you resize all the images in a notebook section?

I've pasted a large number of photos and they are too big which makes scrolling hard. Is there a way to automatically have Mathematica size them to 10% or something reasonable without have to click on ...
1k views

### How to train a convolutional neural net on images?

The functions Predict[] and Classify[] both have the option Method -> "NeuralNetwork", ...
275 views

### Explicit digit-count (precision) of real number

I'm trying to do something which seems like it should be simpler than it is (at least in my attempts at it). I have some code where I read in a list of numbers generated for me by a coworker. These ...
68 views

### AdjacencyList of DirectedEdges in Graph ignore edge direction

I have a simple tree graph with directed edges: In: AdjacencyList[Graph[{a -> b, a -> c, b -> d, b -> e}], b] Out: {a, d, e} I wonder how I can ...
191 views

### How to understand the difference between Sqrt and Log after ClearAll them

I came across this post, here I change the last line of the code Unprotect[Sqrt]; Sqrt[x_] = "blahblah"; Protect[Sqrt]; Sqrt[2] "blahblah" ...
70 views

### Plot of the set complex numbers [duplicate]

I want to show this set (eigenvalues of my matrix): ...
162 views

### ListPlot3D keeps crashing

I have some data, and I want to plot it by ListPlot3D: ...
31 views

### 'MatrixForm' problem [duplicate]

I prefer to use 'MatrixForm' because the form looks better in matrix manipulation. But my current problem is that after the use of 'MatrixForm', subsequent matrix calculations like 'Det' or 'Inverse' ...
166 views

### Calculate efficiently an expensive hermitian matrix

I want to compute a matrix $M_{pq}$, for which the calculation of each coefficients $M_{pq} = f(p,q)$ is an expensive function. I know that my matrix is hermitian, so that $M_{qp} = M_{pq}^{*}$. As a ...
113 views

### How to speed up my code with constructing matrices [closed]

I have run this program for a long time to get the result for n = 2048(about 5hours) and no more result till now (can't run with n = 4096). I would know how to make it more efficient. Any help or ...
325 views

### Check whether array has only constant entries?

I have an array arr with n entries. Now I want to check whether ...
160 views

### Problem using Position applied on matrix with Infinity elements

Am I doing something wrong here? ...
241 views

210 views

### How to compute LLL-reduce basis from lattice in Mathematica? And factor N

original article Clear. What is k? What is suitably large? I already have large numbers. I tried this WITHOUT k: ...
137 views

### Vectorize pixel SphericalPlot

I have a question about Mathematica images exporting. I have created 3d (SpericalPlot) with coloring function on it and then exported it to pdf. Is there any possibility to make more vector graphics ...
168 views

I have some packages that uses database connections inside it, let's call it ConnPackage. The connection IP is a public package variable, and has a default value: <...
90 views

### I'm trying to iterate a function with two variables [closed]

I have a function that calculates temperature that is dependent on both temperature and time. I want to be able to iterate the function to calculate a new temperature and then use that as the next ...
310 views

### Orderless pattern matching

The MMA docs state that "In matching patterns with Orderless functions, all possible orders of arguments are tried". Why then does the following not work? ...
324 views

### How to show well the convexhull in 3d?, for a given set of points

I´m trying with ...
553 views

### How to show surfaces as a implicit plot in 3d?

I was trying to show a feasible region with these lines: ...