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

learn more… | top users | synonyms

8
votes
0answers
79 views

How to connect to a video stream?

Is there a way to get a current frame from video streams (especially from RTSP streams)? I would like to connect to a camera in my local network and get a snapshot from it to do some further ...
7
votes
2answers
286 views

Why an extra { when importing .xls?

I am trying to import data from a file. If I import a CVS file, I get: {{a,b,c},{e,f,g}}. For example, two curly brackets. If importing from a .xlsx file I get ...
7
votes
3answers
940 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 ...
7
votes
2answers
992 views

How do I display imported images at actual size?

I know that this is an extremely basic question, but I am having a lot of trouble finding the answer in the documentation. When I import an image (for example, ...
7
votes
2answers
275 views

How to copy and paste $n$ lines from a text editor to $n$ cells?

If I copy from an external editor to Mathematica notebook a block of lines (with a code) line 1 line 2 ... line n then whole text is copied to a single cell. I ...
7
votes
3answers
1k 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. ...
7
votes
2answers
937 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. ...
7
votes
2answers
104 views

Why doesn't Import work with XOWA offline Wikipedia database?

I'm having trouble with importing HTML from XOWA offline wikipedia database. I set up a local server for datamining, but I can't access it with Mathematica. I can request a HTML page with ...
7
votes
1answer
446 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 ...
7
votes
3answers
240 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
4k 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?
7
votes
1answer
239 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: ...
7
votes
2answers
2k 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 ...
7
votes
1answer
112 views

Reading NIfTI-1 files

How can I read NIfTI-1 files (.nii extension) in Mathematica? Are there existing tools for this?
7
votes
1answer
258 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 ...
7
votes
1answer
226 views

How to make Import recognize a new file extension?

I've written an import converter for a custom file format, and it all seems to be working as expected, except for the fallback behavior with no arguments: ...
7
votes
1answer
367 views

Creating time-lapse movies with Mathematica

Well, my question is this: Is that possible to make time-lapse movies with Mathematica? Here is some more explanation: Watch this YouTube video that is a wonderful example of time-lapse movies. ...
7
votes
2answers
819 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 ...
7
votes
1answer
2k 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: ...
7
votes
1answer
924 views

Import file from FTP site

I would like to Import files from an FTP site. The code below works on a test site: file = Import["ftp://test:test@ftp.secureftp-test.com/pigs.xml"]; But when I ...
7
votes
1answer
143 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
387 views

ReadList can't read correctly

Bug introduced in 9.0 and fixed in 9.0.1 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 ...
7
votes
1answer
526 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: ...
7
votes
0answers
381 views

What are the known differences between Save and DumpSave, and how to account for them?

Edit: I changed the title and (slightly) the wording of this question in order to make it more easily answerable. If I evaluate this in Mathematica 9: ...
6
votes
4answers
1k views

How can I get rid of extra commas in Export/Import?

Consider the following example of trying to export the following table: Export["test.dat", {{{1, 1}, {2, 2}}, {{3, 3}, {4, 4}}}, "Table"]; Now I import to see ...
6
votes
3answers
198 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
2answers
133 views

Possible memory leak when importing JSON

Bug introduced in 10.0 and persisting though 10.2.0 This problem that I would like to resolve is how to free memory used Import a file when the file is no longer in use. I have a project in which ...
6
votes
2answers
347 views

How to process binary-encoded data without writing to file and importing?

I am consuming a webservice through NETLink that returns data directly in the response as a gzipped csv file. I can successfully process the data like this: ...
6
votes
2answers
233 views

Import data from excel and store it permanently in notebook

I am trying to write the code for doing the following: by clicking a button, import specific data from an Excel file which I select through a dialog window; input a name for the imported data set ...
6
votes
1answer
227 views

How to use Get on a folder

In the documentation for Get it says: If the file found by <<name is a directory, the Wolfram Language will try to ...
6
votes
2answers
2k views

When importing is it possible to set the delimiter?

When importing a csv file is there a way to set the delimiter. I have a csv that uses ";" as its delimiter. I tried ...
6
votes
2answers
631 views

How to show wireframes on imported Object / Mesh (.obj file)

I've managed to import a Wavefront (.obj) file and store it in a variable like so: ...
6
votes
3answers
420 views

How to SemanticImport Multiple Excel Sheets

I have an Excel workbook with multiple sheets that I'd like to import into a dataset each. With Import I can target individual sheets by their name into a nested ...
6
votes
2answers
979 views

How can I open an Excel file and modify it in Mathematica?

I wanted to ask how can I view an Excel file from a Mathematica notebook and modify it. I have seen a similar question, Open Excel file with Mathematica, but the answer involves .NET. Is there any ...
6
votes
1answer
895 views

Stream CSV files

Ram limitations make import impractical for large CSV files. Is it possible to Stream CSV correctly? ...
6
votes
2answers
145 views
6
votes
1answer
2k views

Reading csv/xlsx data into Mathematica with column headings as list names

It's old question. However, I could not find satisfactory answer. Decided to post this question. I have a .csv file with column heading. How can I import this ...
6
votes
2answers
420 views

SemanticImport mis-interprets CSV

SemanticImport misinterprets rows with trailing blanks. Note the commas in the 2nd column: ...
6
votes
1answer
282 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
3answers
196 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
328 views

How to correctly import data zipped with the “deflate” algorithm?

I'm writing an importer for the GIFTI file format. The details of the format are not particularly important, but the basic idea is that it is a relatively simple XML file which includes binary arrays ...
6
votes
2answers
284 views

Importing multiple images for machine learning classification

I want to create a ML classifier using images just like this example. I have two classes of images in two different folders. Is there an easier way to import all images from both folders rather than ...
6
votes
2answers
654 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 ...
6
votes
1answer
431 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
165 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
533 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
1answer
749 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
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 ...
6
votes
1answer
95 views

Extracting PNG images from AVI movie

I have written the following code to extract all images from an uncompressed AVI movie and to save them as sequential PNGs. ...
6
votes
1answer
295 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 ...