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0
votes
0answers
28 views

Pick out element from array [on hold]

I have the $3\times 3 \times 3$ array: ...
2
votes
2answers
27 views

How to delete certain unwanted elements from an array

Suppose I have an array like so array1 = {{Null,2,3,4,5}, {a,b,c,Null,e}, {w,x,Null,y,z}} Is there some way to selectively remove any element I ...
0
votes
0answers
34 views

how do I multiply two arrays in Javascript? [on hold]

I want to multiply two arrays, as in element per element: [1,2,3,4,5] * [2,3,4,5,6] = [2,6,12,25,30] I am new to JS and just have no clue... Thanks, Pam
0
votes
0answers
23 views

Importing large arrays and releasing memory

I am trying to import huge 3 dimensional arrays (in my case approximately 2GB) which I calculated before and saved in .MX format. Then I want to work with a smaller ...
3
votes
1answer
50 views

Fast list interpolation over common x,y for multiple variables

I have a (long, >50K elements) unstructured list with a header similar to; AList[[1]] = {x,y,z,var1,var2,var3,var4,...,varN} I want to interpolate z, var1, var2, ...
0
votes
0answers
59 views

Is there a command like meshgrid in Mathematica? [duplicate]

Just like the title, I need to do a meshgrid in Mathematica, is there any command like that?
10
votes
3answers
263 views

Sorting Lists of lists of arbitrary length

I'm trying to sort a list of lists. The sublists are defined in length, but the length of the list containing it varies. A simplified set might be: ...
6
votes
3answers
206 views

List Manipulation on Array with subscript elements

I am trying to write a function which operates on an array with subscripted elements. As an example i have the array a={$1_3$,$2_2$,$4_1$}, which means i have 3 amounts of value 1, 2 amounts of value ...
3
votes
4answers
143 views

Plotting recursive from a for loop

our assignment is that we have make a plot for the possition of 1's From the recursive function if a[n-1] is even then ...
-2
votes
1answer
44 views

How do I store values in a for loop into an array and then plot that array? [duplicate]

What my title said and I want to plot the values of the array. still new to mathematica and programming so its hard to formulate my question just right
7
votes
2answers
68 views

Recursive function with array of variables

I am trying to create a recursive function which works with an increasing array of variables. Since the formula is quite complex, i will try to simplify my example to the core of my problem. The ...
3
votes
2answers
257 views

How to create a 'shortest-path link matrix'?

I am currently struggling with a problem in Mathematica. I have a randomly generated weighted Barabasi-Albert graph and a corresponding demand matrix of the same size. I'm generating the graph with ...
2
votes
0answers
75 views

An efficient way to merge a pair of 4d arrays of non regular length lists

Question I have two 4 dimensional non regular length lists of complex values. I have working code however it seems quite slow and I am not sure how I could improve this. Mathematically I am trying ...
1
vote
2answers
60 views

Generating an Array of Vectors

I'm working a lot with nested lists of $(x,y)$ coordinates (of a FEM-like mesh, but that's not important), like so: ...
6
votes
8answers
257 views

Merging lists and adding common elements [duplicate]

I have two 2D arrays where some of the x-values are identical, L={{1,1},{2,2},{3,3}}; J={{0,1},{2,2},{4,4}}; I want to add these lists in the following way ...
1
vote
4answers
100 views

Converting format of list

I have a 2D array, data = {{0,1}, {1,2}, {2,3}}; I would like to convert it such that I get the x- and y-values separately, specifically ...
1
vote
3answers
46 views

Collect the lists

I have a list of lists from which I pick out the positions of the number 1 and then print out these positions for each list. I am having some trouble collecting what I am printing into a list / matrix ...
1
vote
1answer
78 views

Plot Legends and Frame Ticks in Array Plots

Why do the frame ticks go away when PlotLegends->Automatic is inserted in an Array Plot? For instance, the following code produces an Array Plot with Frame Ticks. ...
0
votes
4answers
81 views

Drop row if sum of part of row is equal to zero

My problem is the following: Suppose I have a matrix A which looks the following: ...
0
votes
2answers
70 views

Can `Array` work as `Loop`? [closed]

I got Mathematica code from my friend: ...
0
votes
0answers
24 views

How can I give input to an ArrayPlot [duplicate]

I would like to create a dynamic ArrayPlot so that the squares, when clicked, provide input. Can I use ArrayPlot for this? Or is there something else I should have to use.
0
votes
2answers
62 views

Import array indices from Excel

In an Excel file, I have some numbers which I will use as the indices of arrays. I want to read those numbers and assign them as the array indices in Mathematica. For instance, in Excel I have and ...
0
votes
1answer
74 views

Import a data stored in EXCEL and change it to a Table [closed]

I have an EXCEL file in which large amount of numbers is stored in a column in the first sheet, like data in the column A of the sheet1 of excel file. When I apply the Import function; the data is ...
10
votes
1answer
223 views

Using Mathematica to make a graphics array of circles

I need to make .svg file that contains an array of black circles that all have radii of 5 units ad are evenly spaced apart from each other 32 units. The difficulty in creating this design is the ...
0
votes
1answer
117 views

Finding the first five eigenvectors and values for a 500×500 matrix

I'm trying to find the first five eigenvalues and vectors of a matrix that has the following proporties: ...
4
votes
4answers
134 views

Better way to select all array indexes matching predicate?

I'd like to select (offset) indexes of a number of array points, that match a selection criteria. I can do this by creating a Table of all the coordinates, and then selecting all the values: ...
2
votes
4answers
172 views

Replacing High Densities of 1.s in Very Large Binary Arrays

I am working with very large binary arrays on the order of {100,100000}. It may look something like this. ...
3
votes
2answers
120 views

Replacing Patterns In a List of Varying Length

I am working with an array of data that may look something like this. ...
0
votes
0answers
125 views

Solve function doesn't work

I have the following system of equations that I need to solve: ...
5
votes
2answers
245 views

Labeling a grid

I have m = {{0, -1, -2, -3, -4}, {1, 0, -1, -2, -3}, {2, 1, 0, -1, -2}, {3, 2, 1, 0, -1}, {4, 3, 2, 1, 0}}; And a grid ...
1
vote
1answer
92 views

Generate a list of values with equal number of each value

I want to create a list of 32 values such that from {a,b} I can generate ...
0
votes
1answer
36 views

Generate array of every $n^{th}$ integer between two bounds [closed]

I want to generate the series {1930, 1934, 1938, ..., 2014} with Mathematica. I found that I can use Sum[2014-m*4, {m, 20}] to ...
2
votes
1answer
182 views

Plot 3D boolean Array or matrix in Mathematica

I have been attempting several methods to plot a 3D diagram of a n by n boolean array in Mathematica but none of them produced satisfactory result. I want the $3D$ plot to have a cube when ...
5
votes
1answer
162 views

How to combine matrix with array without cycles?

I am new to Mathematica. And I'm sorry for my English. I have created a matrix ($6 \times 4$) and an array ($1 \times 4$). I want to get another matrix that will have the first element from the array ...
4
votes
4answers
337 views

Efficient method for Inserting arrays into arrays

This is strongly related to the following Questions: Looking for a way to insert multiple elements into multiple positions simultaneously in a list Building matrices by attaching vectors (columns) ...
3
votes
2answers
242 views

Mapping multiple functions over an array

I am looking for an elegant way to Map multiple functions over an array. My problem looks something like this: Consider a list of functions: ...
4
votes
2answers
117 views

Values (or positions) of array row elements within a specified number of positions from target value

I have the need to collect values from the rows of rectangular arrays of arbitrary precision integers, given a target element value and allowed "distance" (positions +/- within the row from found ...
0
votes
3answers
161 views

Padding of matrix

I want to do padding of matrix a = {{x,x},{x,u}}; to ...
10
votes
1answer
214 views

Drop selection of columns from a ragged array

I have an application where I need to drop some arbitrary list of columns from a ragged array (where of course the shortest array rows have at least all the specified columns). E.g., given a ragged ...
1
vote
2answers
162 views

2D Fourier transform of a table - ArrayPlot issue

Recently, I have encountered an issue with ArrayPlot after performing a Fourier transform of a table. Picture presented above is an ArrayPlot of a 2D table. Using Fourier on this 2D table I obtain ...
0
votes
1answer
57 views

Extracting second value of each sublist [duplicate]

How can one get the second value of every array inside the outside array? I have the following data data = {{10, 20}, {30, 40}, {50, 60}}; I want to extract ...
0
votes
0answers
59 views

Generating the set of all three-dimensional binary arrays distinct under rotation and reflection?

How can I automatically generate all possible three-dimensional binary arrays of size $(x_1 \times x_2 \times x_3$) where each array is distinct from all others with respect to rotation and reflection ...
4
votes
3answers
300 views

Finding connected components in an array

I have an $w\times h$ array with non-negative integers. I wish to partition the set of coordinates $(c,r)$ with $1\leq c \leq w$ and $1\leq r \leq h$, in subsets, so that each subset corresponds to a ...
1
vote
2answers
77 views

Unknown limit of an array of area integrals

Could someone explain why Mathematica can't finish computing this limit (this is a limit of an array, when n -> Infinity (n ...
1
vote
3answers
135 views

More elegant/efficient solution to browse through an array

I have an array of lists and want to correlate every list with each other like this: ...
0
votes
2answers
107 views

Specifying an array that may have an unknown number of entries [duplicate]

Say I'm running some process of unknown duration, and during the process, I need to periodically record the state of some variable. If we knew exactly how long the process took, we could simply ...
10
votes
2answers
547 views

Finding all possible solutions to a math mind game

In the example below the letters shall be replaced by numbers. The numbers are from 1 to 9, and each letter has the same number ...
2
votes
2answers
61 views

Specifying an array with a specific number of copies of two elements

To specify an array of length L in Mathematica, where each entry is someElement, I'm accustomed to writing: ...
1
vote
3answers
96 views

Detecting the existence of an element in a subarray with specific properties

If I have an array that looks like this: ...
5
votes
0answers
257 views

How to extract structured array data from DefineDLLFunction in Mathematica

I want to use my Bluechip PCI-ADC acquisition card in Mathematica via his dynamic link library “Bcdll32.dll”; (used to access functions on my PCI data acquisition cards). My problem is the function ...