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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1
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1answer
720 views

How to set path of IMPORT from excel into Mathematica?

I was able to IMPORT from excel data at the start of my project when both the .nb and EXCEL XLS files were sitting in MyDocument (or some other location), but upon moving both files into my Dropbox ...
5
votes
0answers
642 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 ...
4
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1answer
265 views

How can I colorize an imported model?

How can I colorize an imported model from for example 3ds max? I'm trying to find the way to colorize a 3D plot from an imported model with something like this: ...
3
votes
1answer
224 views

ReadList with header and foot lines

I want to do some large data analysis, and i want to be able to import files in a fast way. I tried Import, but it is quite slow; ReadList takes half the time. This is the code I was using: ...
3
votes
1answer
712 views

How do I read a CSV file and remove comments from it

I have very recently started using Mathematica 9.0 Home Edition and am trying to understand it as best I can so please be tolerant ;). I have a file of data (sugar.csv) which contains blood sugar ...
3
votes
1answer
382 views

Running external pdflatex command and importing the generated PDF document

There have been a couple of questions about incorporating labels and equations that were typeset in $\LaTeX$ into a Mathematica notebook. Ideally, this requires running ...
2
votes
1answer
65 views

Registering/detecting an importer by file name extension

I've developed an importer and exporter for FreeSurfer's MGH/MGZ file format; the specific format isn't important, but I was ...
2
votes
2answers
138 views

Animation of moving rectangles in 2D from data file

I am not very familiar with mathematica but I know the basics so I thought I give it a try. For a project I have to animate rectangles moving around in 2D (later also 3D). The data come from a C ...
2
votes
4answers
2k views

Plotting a large number of data points

I would like to know how to plot when I have a large number of points (arround 600) in a specific format: ...
1
vote
1answer
415 views

Making a ListVectorPlot3D from data in an external file

I have a .dat file with six columns: {x y z vx vy vz}, where x, y, z are space coordinates and vx, vy, vz are the vector components. How can I use this file to get ...
1
vote
2answers
281 views

Import large amount of data with time stamps

I have a large data file (150 000 lines) which I want to import in Mathematica. The first few lines look like this ...
-3
votes
1answer
226 views

import Excel sheets by name

I'm importing data from Excel. It appears that the sheet number needed in the Import statement is taken from the order that the sheets appear in the open Excel file. I need to import 2 of the sheets ...
30
votes
3answers
2k views

How to do http POST in Mathematica?

The Import command lets you do a HTTP GET from a URL, like this Import @ "http://merkosoncampus.com/wp-content/uploads/2011/05/higgs-boson.jpg" This sends an ...
19
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1answer
1k views

Web Browsing Automation with Mathematica

I want to build a bot to automate web browsing, this mean something like: filling forms press "submit" buttons find certain text inside pages and so on... How can I do this with Mathematica? The ...
19
votes
2answers
704 views

Why does ImageData need four times more memory?

Background We are dealing with very large TIFF image files that are imported, processed and exported using Mathematica 9.0.1. Many of our algorithms only work with an array representation of the ...
22
votes
1answer
2k views

Programmatically retrieving e-mails from a remote server

Mathematica has a function for sending mail (SendMail) and can import the MBOX format. But what I'd like to do is ...
12
votes
3answers
3k views

Excel Headers --> Mathematica

I have a large Excel .xls file. Miniature version shown below: (formatting should appear as two columns...) ...
18
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4answers
797 views

How to efficiently import videos

I need to do frame-by-frame analysis of videos. I can import the video files I need, but each file is too large to import at once. I can use the ...
6
votes
1answer
189 views

Import iTunes xml data and convert it into a dataset or table

I have an xml file with song data from iTunes (https://dl.dropboxusercontent.com/u/1012958/iTunes%20Library.xml) and I'd like to import it to Mathematica to do some statistics. I get an XMLObject like ...
11
votes
3answers
933 views

How can I transfer mathematical expressions between Mathematica and Maple?

Is there a simple way to copy mathematical expressions between Mathematica and Maple (or at least in one direction)? I mean only expressions built from numbers and predefined mathematical functions, ...
10
votes
2answers
230 views

How to extract a specific element from EXIF photographic metadata?

It's now possible to import photographs into Mathematica and import the EXIF data at the same time: i = Import["ExampleData/coneflower.jpg", "ImageWithExif"] ...
9
votes
4answers
374 views

Exporting data extensions in fits file

Context In Astronomy the de facto standard for images and data is FITS. I would like to export heterogenous data sets into a single fits file. Attempt I am interested in exporting into a fits file ...
8
votes
2answers
3k views

Import selected columns from a tab delimited text file

I have a very huge file (1GB) from which I desire to import only the 5th column. It is a tab delimited text file with a .txt extension. Can you please help me with ...
7
votes
1answer
362 views

Converting XMLElement objects to plain text

Short version: How can I convert an XMLElement that represents part of a HTML document to plain text? Long version: The more general problem is extracting ...
6
votes
1answer
145 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 ...
15
votes
1answer
305 views

Why does ImportString[“1c”, “Table”] eat the letter c?

I have some whitespace-separated matrix data that I read with Import[..., "Table"]. The data contained mixed strings and numbers (the strings are for row and ...
11
votes
4answers
1k views

Import[ ] drops leading zeros from data when importing a CSV file

I need to load data from the CSV file shown below. Import[ ] drops the leading zeros in column 3 when it imports the CSV file, but they are security identifiers, and I need them. ReadList[ ] ...
8
votes
1answer
507 views

How to properly DumpSave & Get Global`s symbols inside packages while not touching Global context?

For efficiency reasons I prefer to use DumpSave instead of Save. For ease of access I prefer to save symbols in ...
7
votes
3answers
572 views

Skip header lines on import

When importing a data file what are the comment symbols for Mathematica? That is, given a file like this blabla bulbul 1 2 6 54 7 ... .. what symbol do I have ...
5
votes
1answer
692 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 ...
4
votes
2answers
219 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 ...
20
votes
2answers
407 views

Is Compress[] compatible between different Mathematica versions?

Compress[] was introduced in version 6 of Mathematica. It gives a compressed version of expressions represented as a string of ASCII characters. It preserves more ...
10
votes
1answer
493 views

How to import date (YYYY-MM-DD) data from a file?

I have a file with data in form {date, value}: 2010-05-19 17 2010-05-20 20 ...
9
votes
2answers
786 views

How can I animate a set of points imported from file?

I have an external program which generates a set of data - X points at the time t1, X points at the time t2 and so on. These points are stored in CSV file and I can change the format if necessary. ...
9
votes
3answers
1k views

Importing HDF5 with compound data

I am looking to Import HDF5 data with compound data. It appears, at least from what I read, that Mathematica 8.0.4 (and previous versions) does not support reading ...
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 ...
4
votes
1answer
166 views

How to transform a DumpSaved .mx file to .m file conveniently?

I have many DumpSave-d .mx files under a directory. They are generated under Linux. The .mx ...
1
vote
2answers
973 views

Can I improve the importing speed of Excel data?

I have data in an Excel spreadsheet that has 4 rows and 1,000 columns. I am using Import as follows: ...
8
votes
2answers
204 views

Working with Java hashmaps from Mathematica

I'm using J/Link to access data from an external Java program. The data are represented as a ConcurrentHashMap (see the official specification here). ...
7
votes
3answers
295 views

Unencoding encoded URLs in a function

Is there a built-in function for decoding encoded URLs in Mathematica? I would like to convert an encoded URL, for example ...
7
votes
1answer
150 views

Organizing similar datasets using Contexts or otherwise

I often import several long time series to analyze something about a city. When I have multiple cities, I use contexts. As a simple example, ...
6
votes
1answer
176 views

Incorrect result while using SemanticImport for CSV file import

I might use this incorrectly. I want to use a .csv file that (as list) looks like: ...
6
votes
3answers
183 views

Is it possible to Import urls not type “”

These days I often copy urls from Internet Explorer's address bar. When I paste the url into a Mathematica cell it is neither a string nor a expression. ...
6
votes
1answer
184 views

Importing images from the web using ImportString & URLFetch

I can bring images from the web using the Import command like this: Import["http://blog.wolfram.com/wp-content/uploads/2008/06/se-30.jpg"] Sometimes the web ...
6
votes
2answers
699 views

Why does importing a URL fail the second time and produce a FetchURL::conopen error?

I have Mathematica code that uses Import[] to download URLs. I noticed that first time I use the Import[] command it works. ...
4
votes
2answers
304 views

How to save a web page in mathematica?

For a given web page http://www.nytimes.com/, is it possible to save it as : first: only HTML(within css) second: more elements(include pictures and so on) just like what a browser can do. ...
3
votes
2answers
231 views

Speeding up TIF import

After trying to import a $\approx 2$ GB TIF file with the Import command, I noticed that the process takes $\approx 15$ minutes or so, which seems excessive, especially when compared to other software ...
3
votes
3answers
2k views

Import specific data from Excel to make a plot

I need some help with this: I have imported data from an Excel file and I need to make a contour plot of it. The data are in table-like form. Here is a sample of the first few 'rows': ...
3
votes
2answers
785 views

3D scatter plot from a txt file

I have a txt file with space-delimited x, y, z coordinates of several points. The points are organized into groups of unequal size; the groups are delimited by skipping a line, like this: ...
3
votes
2answers
326 views

Extracting a single layer from a SHP file

I have an ESRI ShapeFile (SHP) that I've loaded. It has a number of layers which I can see the names of by using: Import["file.shp", "LayerNames"] I get ...