Questions about getting data, files, images etc. from various formats into a form that can be read, tranformed and manipulated by Mathematica

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6
votes
3answers
189 views

Organizing similar datasets using DownValues instead of Contexts

In his answer to this question, Leonid helped me find a way to programmatically generate contexts for holding sets of symbols with the same names. Perhaps a simpler way is to use ...
6
votes
1answer
324 views

Operations on online files via public URL access

I need Mathematica to access an online public directory via some URL (fake in this case) http://example.com/images and perform operations similar to those Mathematica can do on OS directories and ...
6
votes
1answer
122 views

Can I read Chinese characters with ReadList correctly?

Just try this example: Export["a.txt", "这乱码问题该怎么解决呢\n***\n怎么解决嘛"] ReadList["a.txt", Record] ...
6
votes
1answer
532 views

Import numeric values from XML

I am trying to import data from an XML file and then perform calculations on those numeric values. When I import the data the values seem to be stored as strings. I tried using a ToExpression ...
6
votes
1answer
146 views

Reading specific entries from a CSV file

This question is related to the following: Speeding up Import and Export in CSV format Stream CSV files Reading periodic elements from a large file I have a set of very large CSV files (a few ...
6
votes
1answer
386 views

Accessing data on local machine from remote kernel

I have a remote kernel on a server that I would like to use to process some data. The connection works, i.e, I'm able to use the local front end and the remote kernel. However, I cannot figure out how ...
6
votes
2answers
591 views

Trying to extract information from an MDB file. Import is too slow

I am running a Linux box and as usual the documentation for this type of box is not great. I am trying to open up and extract and possibly include later on information from a "mdb" file. The file ...
6
votes
1answer
295 views

ESRI shape files

ESRI shape files (shp): importing the polygon data can yield a very large list. It is computationally intensive rendering the polygon. I have been trying to convert to ...
6
votes
1answer
218 views

ReadList can't read correctly

I'm trying to load some data into Mathematica from some files generated by fortran. But ReadList seems can't get the number correct. Here is a simplified version of the problem: ...
6
votes
1answer
333 views

Importing DICOM images

When I try to Import individual DICOM (.dcm) files from http://www.osirix-viewer.com/datasets/ datasets I can see the Elements listed in example files, ie: ...
5
votes
2answers
430 views

How to test if file exists and stop

At the moment I'm using > ...
5
votes
4answers
2k views

Numerical Differentiation using 1500 data points

I have a set of 1500 data points (which are some energy eigenvalues) corresponding to a parameter H0 (which represents magnetic field. H0 values are equispaced going from $-3.0$ to $3.0$ in steps of ...
5
votes
1answer
115 views

How to use RunProcess to import external function?

I have a functions written in an external language called GO. How can I quickly load them into the kernel for use as Mathematica functions? The two ways I've tried are with MathLink and LibraryLink ...
5
votes
3answers
278 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. ...
5
votes
2answers
324 views

How to import a “.numbers” spreadsheet?

Does Mathematica support importing a ".numbers" spreadsheet file (from the "Numbers" '09 (ver. 2.3 554) spreadsheet program in Apple's OS X iWork office suite)? A ".numbers" file is actually a zip ...
5
votes
1answer
437 views

Failing to import an .eps file

I have an .eps file which was created using GLE. There is nothing wrong with the file, GS View can read it correctly. However, when I use Mathematica to read it using ...
5
votes
1answer
171 views

How can I read compressed .Z file automatically by Mathematica?

When I read .Z file by something like jpldatstring = Import["ftp://cddis.gsfc.nasa.gov/products/jpl/2003/jplg0040.04i.Z"] Unfortunately, it turned out that ...
5
votes
1answer
128 views

Tools for Importing/working with SEED seismographic data in Mathematica?

Do you know if exist a library or a package in order to import and work with SEED Seismographic data in Mathematica?
5
votes
1answer
277 views

windrose with data from Excel

How to Import data from excel and use them to Plot windrose instead? Example, {{Strength, Angle(degrees)}..} ...
5
votes
1answer
340 views

How can I log in to my Wikipedia account and access my watch list?

Wikipedia's "Edit Watchlist" page (for logged in users) has a list of hyperlinks to the user's watchlist (here is an example from my account). I've tried to use ...
5
votes
1answer
493 views

Open data file from CDFPlayer?

Using a CDF program running in CDF Player, is it possible to use a system dialog box, or even just an Import statement such as Import["*.CSV"], to import data from a text or comma separated file on a ...
5
votes
1answer
289 views

Mathematica 10 doesn't support path containing Chinese characters

I tried to import file in Mathematica 10 ( windows 7 system), the path contains some chinese characters. After holding ctrl+shift, and drag the file into front end. I got path like ...
5
votes
1answer
626 views

Importing specific elements from JSON

I'm having trouble importing JSON in the way I expect, based on my reading of the documentation. The particular issue I'm having is with importing a specific element, or list of elements. From the ...
5
votes
1answer
1k views

Combine multiple PDF files into one document

I have multiple single page PDFs I'd like to join together into a single file. (Obviously I mean the file format and not the probability distributions here!) I'm aware of free online services such as ...
5
votes
1answer
695 views

Efficiently exporting many images as a video

I have many .gif images and I would like to export them as a single video file (I prefer .mov, but any video format is fine). But what if I have several tens of megabytes of .gif images? Is it ...
5
votes
1answer
465 views

ReadList can't read from file containing high-precision Reals

I want to read a file which contains seven columns of real numbers. Mathematica seems to have a problem with the high precision I need. My code: ...
5
votes
2answers
351 views

Change character encoding for file read using OpenRead

I have a large bzipped file that I want to read using OpenRead on a pipe with UTF8 encoding. Doing the following does not give me UTF-8 encoding. My ...
5
votes
1answer
1k views

When do I use Mathematica, when do I use Gephi, and how do I use them together?

Mathematica has great operations for analyzing graphs but when the graphs are a bit bigger, Gephi seems to be more efficient (at least on my computer) at drawing and analyzing, i.e. visualizing the ...
5
votes
2answers
267 views

How to remove an expression from a file?

To read in expressions from a file, one can do ReadList[file, Expression, 3]. How to do the opposite, i.e. remove a number of expressions from a file, modifying ...
5
votes
1answer
168 views

How to write an import converter that can import split and compressed files

First of all sorry if this question isn't formatted properly. I'm working with a data format that prescribes separate header and data files, so for instance ...
5
votes
1answer
242 views

How to import non-text data from std input in a Mathematica script?

Or maybe a better question is - how can I get a stdin stream? I need to run on Linux. I did look at Reading from STDIN, or: how to pipe data into Mathematica, but ...
5
votes
1answer
143 views

Importing Data with Line feeds

I am trying to import data from a CSV file into Mathematica that contains line feeds in certain elements that I wish to be properly rendered in Mathematica. I suppose this has something to do with the ...
5
votes
1answer
401 views

Reading in Huge Text Files

I would like to read in really large text files (about 2GB) into Mathematica. The structure of the file is such that the first row and the first column are text i.e strings. Rest is all numbers. Is it ...
5
votes
1answer
209 views

How to import numbers or protected signs from .txt?

I'm new here, so please apologize any formal errors. I stumbled upon a somewhat simple problem. I want to import plain numbers or protected signs like Pi, ...
5
votes
0answers
655 views

Import Large Excel File

Currently, I am working on a large time series dataset, which contains 928,586 rows and 35 time intervals in columns, in excel format (.xlsx) and using Import to ...
5
votes
0answers
61 views

Importing .zip file [duplicate]

Possible Duplicate: Importing Zip files I have a piece of code which imports a txt file and turns it automatically into a table form. I use the following: ...
5
votes
0answers
125 views

What is the best way (lossless) to import .skp files into Mathematica?

I am using the free version of Google Sketchup and I've got a few designs in hand, which I need to be able to import into Mathematica. I saw the similar question asked by @Sjoerd C. de Vries in Stack ...
4
votes
2answers
615 views

Check Google PageRank for a given URL

Does anyone know how to write a Mathematica function that returns the Google PageRank of a given URL? I found a tutorial for achieving this in a bash script here, but I have no idea how to port this ...
4
votes
3answers
302 views

Plotting data with exponentials

I have some data with 19000 sublists such as : {" 7.9080000e+01 1.9283193e+04"} Where the first number is the value for variable ...
4
votes
3answers
196 views

Reading binary strings from file as strings

I have a file that contains binary strings like 01011 00101 01011 I want to import the file to Mathematica as a list of strings, but ...
4
votes
2answers
135 views

Workaround for Import not supporting the \leqslant TeX macro

$\{A\leqslant x\leqslant B\}$ Copy the code into Notebook, and you'll lose the less sign, this can be rendered well in ...
4
votes
2answers
916 views

How to process .vtk file

I want to extract the cluster of points inside 3D box, is there any way one can do this in Mathematica?
4
votes
2answers
298 views

Image Rotation, Line Symmetry

I'd like to import an image, superimpose it, reduce the opacity of the overlaid image, and then use a manipulate to rotate the top image to illustrate rotational symmetry. The image below is using ...
4
votes
2answers
450 views

Importing array with complex numbers

This is probably an easy question: I am exporting the results from a longer calculation into a dat-File, then I set the cell to non-evaluatable and put an Import in front, so I can later work with the ...
4
votes
1answer
2k views

Importing CSV financial data in Mathematica

I am trying to import a CSV file in Mathematica 8 with the aim of charting it with the TradingChart command. This is what I have done : ...
4
votes
1answer
151 views

CSV vs XLS for import

I need to import data from various database sources. At the moment I plan on importing files via a CSV file or XLS. All the data if in XLS would be on one sheet (notebook). Are there any advantages ...
4
votes
1answer
238 views

How to clean up messy data

The start of my question is about one specific situation - I have some erroneous lat/long values in a dataset which I need to clean up. But I'd like it to cover the overall topic of cleaning up messy ...
4
votes
2answers
220 views

Sorting a large file

I have some huge logs, which are text files, containing up to a million rows each, and I need them sorted. Because trying to import one obviously makes Mathematica run out of memory, we must rule out ...
4
votes
2answers
136 views

Equivalent of __FILE__?

Many languages define a special identifier whose value is the path to the source file currently being processed. (For example, in C, this is done through the ...
4
votes
1answer
119 views

Why can't an `Import[]` change $Path?

Does anyone know why Import["http://**server**/file.m"] can't make a change to $Path? It seems like ...