Questions on the use of the Table[] command and other functionality related to lists. Use [tag:matrix] for matrix algebra and related methods, and [tag:list-manipulation] for questions about transforming or operating on existing lists.

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39
votes
6answers
2k views

How to visualize/edit a big matrix as a table?

Is it possible to visualize/edit a big matrix as a table ? I often end up exporting/copying big tables to Excel for seeing them, but I would prefer to stay in Mathematica and have a similar view as in ...
20
votes
5answers
1k views

Instruct a Table to only evaluate until a condition is fulfilled

I am looking for the way of building a Table of pairs of numbers in a fast way. My true table evaluates huge functions, and I see no way and reason to show those cumbersome expressions here. Let us ...
13
votes
6answers
917 views

Calling Table with custom iterator

I often find myself in situations where I, for example, need to build a table for some expression, but want to set the number of points rather then the step size, so the code ends up looking like this ...
10
votes
2answers
791 views

Is there a Break[] equivalent for short-circuiting in Table?

I am running Mathematica 7. The following is admittedly a silly example, but suppose that I have a list list whose entries are either ...
8
votes
3answers
585 views

How do I avoid scoping collisions of iterator variables?

Yesterday I had an issue that kept for quite a while. My code wasn't producing the right results. Now I know why and I am wondering how to avoid the issue in future. Consider the following code. <...
6
votes
2answers
1k views

Table of Variables

I use a list of variables {x1, x2, x3} to Solve a particular set of equations. I am now trying to generalise this depending on ...
3
votes
3answers
4k views

Importing multiple files using a for-loop

once again I am stuck solving a seemingly easy problem :( I would like to make a List of tables by importing data from several txt-Files. Importing the data into a table works so far and I am able to ...
1
vote
3answers
2k views

How to create functions of arbitrary number of variables? [duplicate]

In the following code what would be the simplest way to generalize it to say some $N_f$ number of $z$ instead of just $z_1$ and $z_2$? ...
4
votes
2answers
228 views

Mysterious behaviour of ParallelTable

This question is related to Export bug in combination with ParallelTable?. The following code shows an even stranger bug than in the upper question. The y-axis should always be logarithmic, but in ...
8
votes
1answer
202 views

Export bug in combination with ParallelTable?

I am programming with Mathematica 10.3.1.0 on Windows 10 Professional 64 Bit and have an i7-4940-MX 3,1 GHz processor (4 cores). When I use in the example code below ...
12
votes
5answers
482 views

TableAlignments -> Left not working

Bug introduced in 7.0 or earlier and persisting through 10.1.0 or later For a very simple dataset TableAlignments->Left does not work: ...
2
votes
2answers
213 views

Problem with NumberForm when exporting

I have a two-part question regarding NumberForm First question In my attempt at answering this i stumbled upon a strange behavior by NumberForm when the final result is exported. Lets say I ...
5
votes
2answers
473 views

Single Legend for a Table of Plots

For this toy problem ...
2
votes
1answer
69 views

Operations on dynamic arrays [duplicate]

When I do a simple operation like this fib = Table[Fibonacci[i], {i, 15}] and then look to find the position of a certain value, everything works fine: ...
1
vote
1answer
185 views

direct assignment to the element in a Table

I have already asked a related question here why set values in this way doesn't work? But I think I have to write the question which I encountered explicitly? ...
1
vote
1answer
566 views

Can Table be used inside Manipulate?

EDIT: CHanged the code. Please try again t see if it works well on our PCs. I am creating a simple Manipulate[] notebook. However when I place Table[] in the code, like: ...
3
votes
2answers
85 views

Faster use of Condition for a large array (see the example)

Here is the example/problem. I have a array of $n$ random number. n = 2000; p = RandomReal[{0, 9}, n]; I have to create a $n\times n$ sparse matrix with $(i,j)$...
2
votes
2answers
1k views

Get positions of all non zero matrix elements

I want to find all non zero elements of a table and I want to create a list that contains the name of the table the element was removed from, the position of the element, and the value of the element. ...
2
votes
2answers
587 views

Create a matrix of matrices using Band and ArrayFlatten [duplicate]

I can easily write a simple Band matrix using: SparseArray[{Band[{2, 1}] -> a}, {Dim, Dim}] where a is a number. Now, I ...
1
vote
1answer
314 views

How to use Table to assign values to variables in a list?

I'm trying to do the following: R = {a, b, c, d, e, f, g, h, i}; Table[R[[n]] = RandomInteger[{0, 20}], {n, 1, Length[R]}] My intention is to assign a random ...
16
votes
3answers
1k views

WYSIWYG table creating and editing

In Microsoft Office OneNote 2010, creating and editing tables is easy. There are simple toolbar controls for creating tables: , and editing them once they exist: . My question is, what's an easy ...
10
votes
5answers
880 views

Relational joining of tables

A common thing to want to do with data is to combine it (at least I thought this was a common thing). In SQL there is the idea of table joins "select id,v1,v2 from A,B where A.id=B.id" kind of thing. ...
3
votes
1answer
327 views

How can I create a colour image using raw black and white data? (FITS data cube)

I have a data cube containing pictures of a galaxy across a thousand wavelengths. I want to take the data for the image slides in the red and blue parts of the spectrum, and have them represented in ...
12
votes
7answers
628 views

How to properly inject iterators into table? [duplicate]

Goofing off on a prior question, I was fiddling with other methods, which led me to the need to inject a constructed set of iterators into a table construct. Now, ...
16
votes
16answers
2k views

Generating a list of numbers that are not multiples of 4

I want to write simple code that will list all numbers from $1$ to $n$ that are not multiples of $4$. And in this case I consider that ...
4
votes
1answer
350 views

Errors when using ParallelTable inside a package

I'm developing a package that contains a function that requires evaluation of an expensive Table, so I use ParallelTable instead....
5
votes
2answers
200 views

Why doesn't ParallelTable work on this very simple example?

For some reason, I'd like to use ParallelTable with a variable number of iterators. Table[a[1], {a[1], 0, 10}] works fine: ...
3
votes
4answers
271 views

AccountingForm w/o significant figures

Basically I want to build a chart like something I would do in Excel. It should look like this: Here is the formula I'm using and what I've done so far ...
6
votes
2answers
310 views

Interactive grid

I would like to create an interactive grid, whereby one number from a grid is selected by the cursor ("3" in the example below), and all other numbers in the grid are highlighted that are related to ...
5
votes
2answers
675 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 ...
4
votes
2answers
152 views

Use the value of a cell in a table as the argument to a function

I just got Mathematica from my school and I'm trying to learn the basics. How could I use the value of a cell in a table (as in Insert->Table) and pass it as an argument to a function whose value is ...
3
votes
2answers
245 views

Problem with exporting lists to Excel

When I use the form Export["file", list, "Table"] to export a list to Excel, I get columns of lists. I want my Excel sheet to have each list element in a separate ...
2
votes
2answers
245 views

Generating an editable table that can be used as input

Say I have a number $n_{max}$. I want a command to generate a table like 1 1 2 2 3 3 4 4 ... nmax nmax where the second column is editable, and this table can be ...
2
votes
1answer
109 views

Why isn't Table iterator value inserted in failed NIntegrate arguments?

Consider this simplest example: Table[{z, NIntegrate[f[x], {x, 0, z}]}, {z, {1}}] Here f is not defined, so ...
1
vote
1answer
83 views

Deleting vertices from Graph and preserving Structure?

My goal is to remove vertices from graphs (and the edges from them) and then take GraphComplement to find out cut sets in graphs with sink and source such as here. So How can I delete vertices from a ...
0
votes
1answer
383 views

Function to marginalize a table over given parameters

Let us say I have generated a table tab with entries {p1,..,pd,chi2[p1,..,pd]} of dimension ...
6
votes
1answer
133 views

Smoothing out data points in a ListDensityPlot

I stumbled upon this problem when I was trying to make some nice smooth ListDensityPlots of my numerical data. In short, my problem is that I let Mathematica plot two copies of basically the exact ...
5
votes
5answers
252 views

How to make a table of $\sum_{i=1}^n$?

I want to create a table of $\displaystyle \sum_{i=1}^n i^k$ for $1\le k\le 5$. The output I want to obtain is a TeXForm output as follows. \begin{align} \sum_{i=...
4
votes
1answer
661 views

Create a table with inline conditions

I am trying to create a table with conditionals inline. For example, I'd like to create a 2 dimensional table like this: ...
3
votes
1answer
425 views

Why can't Mathematica parallelize this?

The following code makes mathematica print "ParallelTable::nopar1: [...] cannot be parallelized; proceeding with sequential evaluation." ...
3
votes
1answer
696 views

Exporting/Importing a Table of complex numbers

I'm generating a long table of list of the form: PN={{1,2,1+i},{3.5,2.6,2}...},{...},... Using: Export["PN.dat", PN, "Table"] ...
3
votes
5answers
443 views

Creating a conditional table

I'm trying to create a conditional table. Let's say I want to have such result: {1,2,3,4,5,0,0,0,0,0}. The idea is to create a table of n elements (10 in a given example), but when one element takes ...
2
votes
3answers
177 views

One-column table not properly displayed by TableForm

I want a table with a single column of data, and with headings along both the rows and the column. One might expect it to work like this: ...
2
votes
1answer
134 views

Multiple plots using dynamics

I am studying Dynamic and DynamicModule, and I have tried to make a simple plot of a family of real functions. The number of functions should be a dynamic variable controlled by a slider. So I have ...
2
votes
2answers
215 views

Replacing all values in a table > $T$ [duplicate]

I want to generate a table of Euclidean distances from the points in a list to a given point, e.g.: ...
2
votes
5answers
172 views

Turning Pascal's Triangle 90 degrees counter clockwise

I have a function that returns a list containing sub-lists that have the numbers for each row in the list. (ex.{{1},{1,1},{1,2,1}}) If I was going to represent it regularly I would use table form and ...
2
votes
1answer
81 views

Performance of a bootstrap - time of computation not linear with number of iterations

I'm doing a bootstrap based on this thread with the following code (file.txt here): ...
2
votes
1answer
77 views

issue with Animate

I want to make a animation based on the dataset like data = Flatten[Table[{x, y, x^2 - y^2}, {x, -3, 3}, {y, -3, 3}], 1]; I show this data using a ListPlot3D. <...
1
vote
2answers
62 views

Error Resulting from Placing a Dynamic Variable inside of Table

I want to create a list of values, True or False, and to update those values with a Checkbox....
1
vote
2answers
164 views

`Slot` (#) interfering with evaluation

In the following I am using one function makeFunc to assemble two functions a[t] and b[t] to ...