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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19
votes
2answers
662 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
0answers
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 ...
12
votes
3answers
2k views

Excel Headers --> Mathematica

I have a large Excel .xls file. Miniature version shown below: (formatting should appear as two columns...) ...
17
votes
4answers
673 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 ...
9
votes
2answers
714 views

Exporting data from Excel into Mathematica using clipboard

I know that it's possible to import Excel data into Mathematica using the Import command, as we can see in this post. But some times, I need just to do some fast ...
11
votes
3answers
706 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
215 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
1answer
649 views

Dealing with large files

I have a *.dat file in which the contents are basically one giant list: {1,2,3,4} {5,6,7,8} {9,10,11,12} and so on. I'd like to read in the first 500 members { ...
7
votes
1answer
307 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 ...
11
votes
4answers
951 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
2answers
2k 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 ...
8
votes
1answer
450 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 ...
4
votes
1answer
616 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 ...
17
votes
2answers
384 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
452 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
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 ...
6
votes
1answer
635 views

Stream CSV files

Ram limitations make import impractical for large CSV files. Is it possible to Stream CSV correctly? ...
5
votes
1answer
966 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
132 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 ...
3
votes
1answer
76 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 ...
1
vote
2answers
926 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: ...
7
votes
2answers
177 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
278 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
144 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, ...
7
votes
3answers
641 views

Efficient image Import

I have several sets of 20 images I need to import. Each time they have different categories. "Name"<>"Cat"<>"No" Electric B 1 for example. I need to create lists that contain the images ...
6
votes
3answers
177 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
166 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 ...
5
votes
2answers
627 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
1answer
362 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
votes
2answers
282 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. ...
4
votes
2answers
4k views

Importing from Excel

I'm trying to import a matrix from Excel to Mathematica. My code is: Import["desktop/stproj.xls", "xls", data, 1] The output is some weird stuff about population ...
3
votes
3answers
1k 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
655 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
281 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 ...
3
votes
1answer
288 views

Mathematica - set end-of-line characters when importing

I have a plain text file of tab-separated values that was created on a Windows machine. I want to import it into Mathematica on a Mac. ...
2
votes
2answers
375 views

video image recognition [closed]

Has anybody experience with video and image recognition? I've made a video of two teams playing soccer. Now I would like to translate each soccer-player to a (x,y) coordinate and follow them during ...
0
votes
0answers
220 views

Determining if a point is inside or outside a 3DS (.3ds) or 3DS MAX (.max) object?

Imagine I import some 3DS (i.e. 3D studio) file (http://reference.wolfram.com/mathematica/ref/format/3DS.html) or a 3DS MAX file. How could I place this model (say, the 747.3ds file in the ...
8
votes
3answers
471 views

Import values from tab separated file, change decimal point?

I have files that look like this: ...
7
votes
1answer
123 views

Using Differences on data: trouble with floats and doubles

Consider the following data set (after I have run FullForm), which is imported from a file (stored typically as 10.040): ...
7
votes
1answer
1k views

Import DCD (CHARMM/NAMD binary trajectory) file

How can one import the coordinates stored in a binary CHARMM/NAMD DCD file? This is the structure of the file: ...
4
votes
2answers
1k views

Converting numbers to integers

I've read the available documentation but I still haven't found an NumberForm -> Integer function yet. No result in this site's search, either. Does it exist? ...
4
votes
3answers
293 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 ...
3
votes
2answers
222 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
1answer
371 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
1answer
492 views

Mathematica PDF import and fonts

I am trying to put nice LaTeX labels on my Mathematica plots. I can do this manually, or by introducing an extra GNUPlot step into my workflow, but it would streamline the process considerably if ...
3
votes
3answers
502 views

How can I change the CDF which imports the data and uses it, without execution of code

I am making an application which first imports the data from the Excel file and then uses it in the deployment of a CDF. But is it possible to change the data of the Excel file and see its ...
3
votes
3answers
330 views

Support for Compressed Sparse Column sparse matrix representation

Is there native support for Compressed Sparse Column (CSC) format for sparse matrices, like importing and manipulating them?
2
votes
0answers
61 views

Antialiased text in manipulate constantly re-evaluated, ignores TrackedSymbols

I am trying to display antialiased text (using the ImportString[ExportString[]] method shown here) but inside a manipulate so that the text can be changed interactively. I have found a way to do this, ...
2
votes
1answer
115 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: ...