Linked Questions

6
votes
3answers
4k views

Save and call matrices with large output in Mathematica [duplicate]

If we have the large matrix A=RandomReal[{-10, 10}, {1000, 1000}]; and I need it for further calculation, how can I save it on hard disk and then call for ...
2
votes
1answer
3k views

How to export/import function values [duplicate]

I have a function with two variables: f[x_,y_]:=f[x,y] = ... I calculated some values (they are fractions like 435345345/3424242424) and would like to store the ...
4
votes
1answer
3k views

Can an Interpolation function be 'saved'? [duplicate]

Possible Duplicate: Save interpolated function I am importing tables with sizes of 100k - 500k rows and 4 columns. The larger the table, the slower my Mathematica runs for all computations after ...
2
votes
2answers
232 views

How to store an InterpolatingFunction? [duplicate]

Assume I have obtained an InterpolatingFunction, say, as the result of solving of a differential equation, say, this one: ...
2
votes
3answers
279 views

How to store the nonzero elements of a sparse array in a file? [duplicate]

Often I need to use same matrix several times and for that I save them in an external file. Converting the matrix into SparseArray can save a lot of space in this ...
1
vote
1answer
716 views

How to store a SparseArray? [duplicate]

How to Export/Write a SparseArray? How to Import/Read a SparseArray? Is it always stored as a normal array? How can it be stored in a dense form? Is a numerical SparseArray different to Export/Import ...
2
votes
1answer
751 views

Export mathematical expressions for further reuse [duplicate]

I am dealing with a program with Mathematica where I compute expressions that take a very long time to compute. I need these results for further computation and/or display. I would like not to have to ...
2
votes
2answers
397 views

Exporting arrays for storage [duplicate]

I have a set of arrays I would like to output to some file ArrayStorage.txt s.t. these arrays could be read-in to a separate notebook on a separate kernel. Is ...
0
votes
0answers
291 views

Assign variable's value programmatically [duplicate]

Not easy to explain what I'm looking for, so please sorry if I'm not so short. Having many variables to be managed in several different combinations, I need to automate the assignment of preset ...
2
votes
1answer
104 views

How to use external Mathematica Code? [duplicate]

I have a Mathematica Notebook with a function that i would like to be able to access from another Notebook without having to have the first Notebook open. The functions calls other functions in the ...
1
vote
0answers
208 views

Transferring a list from one notebook to another [duplicate]

I have Mathematica code split into two notebooks. The first part is supposed to run and output a list of numbers into a text file, using Export. The second part ...
0
votes
1answer
148 views

How to save a list of analytic expressions in a file? [duplicate]

I use Mathematica to calculate many analytic expressions, some of them are generated by a loop process, the result can be a vector with a index, e.g., f[i]. Now ...
3
votes
0answers
64 views

How can I append Mathematica variables to an output file preserving both names and values? [duplicate]

I have a Mathematica program that calculates a series of large vectors that I need to save for future reference (in addition to some scalar values). I want to save all these to a file, tagged by their ...
0
votes
0answers
51 views

DumpSave a variable in Do loop [duplicate]

I have the following code: ...
0
votes
0answers
51 views

Using data of a compiled code in future [duplicate]

I have run a huge amount of code to find a 9 by 9 matrix called A. I want to use elements of this matrix in future when I open the Mathematica again. Is it possible? How can I do that? An step by step ...
1
vote
0answers
47 views

What is a good way to import interpolating functions of large size? [duplicate]

I was generating a set of eigenfunctions from a differential equation using NDEigensystem. Because of the computer time cost is too high, I thought it'd be better ...
0
votes
0answers
45 views

Exporting large expression [duplicate]

I generated a huge mathematical expression (~200k terms, impossible to simplify yet) and want to save it for later analysis. Last time I did Export to *.nb file and ...
184
votes
2answers
10k views

What is the distinction between DownValues, UpValues, SubValues, and OwnValues?

When reading through the documentation, you often encounter the phrases DownValues, UpValues, ...
68
votes
7answers
4k views

Functions vs. patterns

Every time I define a new function, I wonder which construct I should use: true functions obtained by using Function, or rule-based syntax. For example, these are ...
60
votes
7answers
15k views

Saving data inside a notebook so that I don't have to run it again?

Piggybacking on this, I am somehow not fully convinced that I can't save data generated by a calculation in a mathematica file so that when I re-launch said file, I wouldn't have to run my ...
116
votes
1answer
7k views

File-backed lists/variables for handling large data

Background Currently I am working with some large data (most of it generated by Mathematica itself). I usually find it a hassle to do this. For example, I just exported a large amount of data to ...
34
votes
2answers
8k views

How to save all data in all variables so that loading it is fast?

I've got this CSV file I've imported that has tens of millions of lines in it. It takes around 20 minutes to import. I've been working with it for a while and have the processed data spread out in a ...
29
votes
3answers
2k views

DumpSave for the forgetful

A few weeks ago I created a big matrix, and in order not to have to recreate it, I stored it using DumpSave["file.mx", variable]. Now I want to read it back in and ...
49
votes
3answers
3k views

How to distribute proprietary Mathematica code

If I want to make package-code completely unreadable, in a way that the end-user can only call my functions, but has no way to re-engineer my definitions, how would I do that? I know I can use ...
34
votes
2answers
2k views

When to use Get vs Needs

When should I use << vs Needs? I just always use Needs as ...
14
votes
4answers
8k views

How do I save/export a list so that it can later be easily imported as a list again?

I have a couple of big lists (each of them contains elements that are themselves lists of two elements, i.e. an element of each list that I have is of the form {x, y}) that I want to save/export. ...
10
votes
3answers
582 views

Find variable name from DumpSave on a scoped variable

I saved an InterpolationFunction in a ".mx" files using DumpSave on a variable that was scoped by a ...
8
votes
1answer
6k views

How can I save and recall my own function?

In MATLAB, I can save and recall my own function using an M-File(function or script) How can I do something similar in Mathematica? I already searched and know how to define functions and modules ...
12
votes
3answers
693 views

Exporting and reimporting a list of lists changes the dimensions

Could anyone explain to me what in the world is going on here and please help me in reading in dummy.dat properly? ...
4
votes
2answers
2k views

Save variables values and definition

I used to do a lot of programming in R and recently switched to Mathematica. One thing that bothers me is that I haven't found a way to save variables, their values and definition! Let's look at an ...

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