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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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
631 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 ...
10
votes
3answers
671 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
214 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
617 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 { ...
6
votes
1answer
290 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
913 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
439 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 ...
6
votes
1answer
143 views

Assign the contents of a “Copy” operation programmatically to a variable?

While an earlier question Cut and paste data from a spreadsheet nominally addresses the issue, a year has past since its OP asked it and I hope that others have come across simpler or more direct ...
6
votes
1answer
662 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 ...
4
votes
1answer
596 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
380 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
439 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
975 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
620 views

Stream CSV files

Ram limitations make import impractical for large CSV files. Is it possible to Stream CSV correctly? ...
5
votes
1answer
940 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
127 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
914 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
174 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
271 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
143 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
3answers
176 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
162 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
592 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
156 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 ...
4
votes
1answer
310 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
277 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
622 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
273 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
276 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
344 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 ...
8
votes
3answers
451 views

Import values from tab separated file, change decimal point?

I have files that look like this: ...
7
votes
1answer
122 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: ...
6
votes
3answers
624 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 ...
4
votes
3answers
290 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
217 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
353 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
480 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
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? ...
3
votes
3answers
480 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
323 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
59 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
101 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: ...
2
votes
2answers
258 views

How can I remove text headers when importing a numeric table

I have a file let's say 1.txt having numbers like: fgdgfdg fhdfdh 0.000105533 1.00E-04 0.222281 1.00E-04 0.444456 1.00E-04 0.666631 1.00E-04 asdas ddfdsfsd 0.111193 0.166733 ...
2
votes
0answers
96 views

Significant platform-dependent efficiency when importing data?

I'm curious, as I understand that answer this way: If you are using a Linux derivative or something like cygwin on Windows, then this is an efficient solution for reading only the third field ...