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
205 views

How can I read in specific information from a TeX-file?

I have several TeX-files and they contain information of the form ...
7
votes
1answer
114 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): ...
12
votes
2answers
431 views

How to monitor the progress of Read?

I use f = OpenRead["largefile.m"] x = Read[f]; Close[f]; to read in a Mathematica expression from a large file largefile.m ...
13
votes
3answers
685 views

How to scrape the headlines from New York Times and Wall Street Journal?

How to scrape headlines from New York Times, Wall Street Journal main pages to create datasets similar to this service? Importing HTML from nyt.com (HTML4) results in a ...
16
votes
3answers
1k views

Is it possible to use Mathematica to record sound and/or vision?

I think the title says it all. I know about ImageCapture which seems to capture stills. Can ImageCapture be made to capture a ...
2
votes
1answer
222 views

How to solve issue with exporting / importing data to and from Excel

Background ( simplified ): When I export data to Excel like ...
5
votes
2answers
335 views

How to test if file exists and stop

At the moment I'm using > ...
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: ...
9
votes
3answers
843 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 ...
11
votes
1answer
216 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
1answer
556 views

Stream CSV files

Ram limitations make import impractical for large CSV files. Is it possible to Stream CSV correctly? ...
14
votes
2answers
2k views

Importing a large Excel file

I'm trying to import a simple Excel file containing 94,000 rows and 52 columns of various types, mostly Reals. It's a 38-MB file. I get this super helpful error ...
31
votes
5answers
3k views

How can I extract data points from a black and white image?

Consider the following graph (source): Is there any way to extract the data points from this image in a semi-automatic way? I have seen, and tried the methods suggested in this question, but they ...
6
votes
1answer
2k views

How to extract sample values from an imported WAV file?

Suppose I read a file with B = Import["something.wav"] Now how can I obtain a list of sample values?
14
votes
2answers
326 views

How to load thumbnail, not image?

Is there any way to import only the thumbnail of an image instead of the full image? I frequently work with lots of images and it would be nice if the contents of a directory could be quickly ...
4
votes
2answers
3k 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 ...
8
votes
1answer
392 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 ...
19
votes
2answers
1k views

Extracting values from nested rules in JSON data

I have been using Mathematica to analyse some data from the StackExchange API. It is conveniently available in JSON form, which Mathematica interprets as replacement rules. However, some of the rules ...
25
votes
3answers
1k 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 ...
6
votes
3answers
187 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 ...
7
votes
1answer
140 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, ...
15
votes
1answer
339 views

Importing Zip files

Mathematica can import zipped files automatically, but when the content of the zip file it's another zipped file, I just get the list of files in the second zip: ...
3
votes
1answer
278 views

Mathematica Import functions fails for data download from website

I am trying to download some data from a website that uses "java enabling" to tell me that I cannot download the data. Using Import[ "website...", "Data"] I get ...
5
votes
1answer
962 views

Difficulties with Importing PDFs in Mathematica

I am trying to import a group of PDFs that I have downloaded (it is in the realm of 1,000+). They are a group of doctoral dissertations that I'm trying to automatically extract bibliographic ...
11
votes
6answers
1k views

How do you skip missing data values in a data file?

In scanning through a simple imported file of weather station data, some dates have missing data. What is a test to use to check whether a datum is valid? I tried ...
11
votes
3answers
389 views

Data of badly formatted file

Similar as in this question, I have to read in data from a file (exampleFile.txt) which is not so well formatted. Unfortunately, I cannot find a solution by myself. Since it is a bit complicated to ...
18
votes
1answer
987 views

How to manipulate web pages on Mathematica?

I wanted to input some data on this page through Mathematica: http://www.fundamentus.com.br/buscaavancada.php Then I would press the "buscar" button also through mathematica coding and get the ...
13
votes
1answer
575 views

Release the web camera after using CurrentImage[]

CurrentImage[] will capture an image from the webcam. It is even possible to create a live video in the notebook using ...
3
votes
2answers
1k views

Importing .txt or .csv financial data

I am trying to import some financial data exported from Excel. You can find the relevant file here : Text File or CSV File This is what the data looks like in Excel : Using the following code to ...
12
votes
1answer
965 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 ...
23
votes
5answers
3k views

How do you convert a string containing a number in C scientific notation to a Mathematica number?

Suppose I have a string containing the C-representation of a floating point number, for example s = "1.23e-5" and I want to convert this to a Mathematica number. ...
48
votes
3answers
4k views

Recovering data points from an image

Unfortunately, some data can only be obtained in picture form (Japanese publications anyone?). Since this cannot be worked with, it has to be converted to a dataset that can; I was wondering whether ...
1
vote
1answer
389 views

How can I speed up image importing? [closed]

The following examples show how slow it is to load a simple GIF. Can anything be done to make it faster? System #1: Mathematica 8.0.1.0, HP notebook, Win7 64Bit, 2 x 2.4Ghz Intel Core i5, 2GB RAM, w/ ...
16
votes
2answers
365 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 ...
15
votes
2answers
464 views

How to develop an Import/Export converter for Compress[]ed data?

Mathematica has a cross platform data exchange format, WDX. Unfortunately importing or exporting large data from/to WDX is very slow. Using MX files is very fast, but they are not compatible across ...
6
votes
3answers
543 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 ...
10
votes
1answer
421 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 ...
4
votes
3answers
276 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 ...
9
votes
3answers
671 views

Is it possible to import dates and times directly as AbsoluteTime and by pass DateLists?

Date and time calculations are quite slow so I am exploring ways to minimize the number of calculations performed. As an example: ...
6
votes
1answer
259 views

Operations on online files via public URL access

I need M. to access an online public directory via some URL (fake in this case) http://example.com/images and perform operations similar to those M. can do on OS directories and files. Examples: ...
19
votes
3answers
1k views

Importing videos in Mathematica

Mathematica's Import command is purportedly able to import .AVI files. However, I find that many files that I want to import do only result in MMA showing a blank ...