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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4
votes
1answer
163 views

Import YAML file into Mathematica

Has anyone implemented the import of YAML data files into Mathematica? I suppose some sort of transformation into a nested list of rules would be the way to do it. Thanks
4
votes
1answer
154 views

Import audio in uLaw format?

How do I import a uLaw-format audio file into Mathematica? Here's an example: hello-world.ulaw For reference, here's the same file in wav format: hello-world.wav As I understand it, the uLaw ...
4
votes
1answer
215 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 ...
4
votes
0answers
107 views

How to speed up import of large csv table?

Loading less than 2 gB of csv data took 5.29 hours: ...
4
votes
0answers
46 views

Import succesful when file manually deleted

apparently Import keeps an imported file i the cache and doesn't complain for some time if a file is deleted manually from the system and then it is imported. If the file is deleted from within ...
4
votes
0answers
139 views

Problem with FTP import in V10

Mathematica V10 returns an error when download directory. URLFetch :: invhttp: "FTP: could not retrieve (RETR failed) the specified file." V9 successfully retrieves the same reference. This ...
4
votes
0answers
103 views

Import Excel data forcing links (ie workbooks) to be updated

We have noticed importing data from an Excel spreadsheet doesn’t update links. The problem with this is if you import a spreadsheet that comprises of linked workbooks data and those workbooks have ...
4
votes
0answers
184 views

Single image import from stack via FTP connection

Background I would like to create a CDF document that is embedded on a webpage. The CDF will contain some image display ...
4
votes
0answers
239 views

Strange behavior of undocumented RawArray and ArrayObject expressions

I discovered several strange results and inconsistencies while trying to understand what undocumented RawArray and ArrayObject ...
3
votes
3answers
3k views

Importing multiple files using a for-loop

once again I am stuck solving a seemingly easy problem :( I would like to make a List of tables by importing data from several txt-Files. Importing the data into a table works so far and I am able to ...
3
votes
2answers
2k 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 ...
3
votes
2answers
664 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 ...
3
votes
4answers
717 views

Importing or reading data in binary format 212

I have a binary data file in format 212, and I want to import the file into Mathematica. How do I read or import binary format 212? I almost have no direct experience of working with any binary ...
3
votes
2answers
260 views

Equivalent of Matlab's uigetfile in Mathematica

I was wondering if there an equivalent of the "uigetfile" Matlab function to use it in Mathematica. To be more precise, I want to read many Excel files and I don't want to type a static path; ...
3
votes
3answers
409 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?
3
votes
3answers
510 views

Import data from first/last 100 rows of a file

If one wants import data from the first three rows of a file "myfile.data", one can use the command Import["myfile.data",{"Data",{1,2,3},All}]; However, if I ...
3
votes
2answers
468 views

Why does a certain CSV file import properly into LibreOffice but not into Mathematica 10.0?

I'm working on a project involving data manipulation and it involves working with CSV files. I know that the files are properly formatted as when I import them into LibreOffice, all of the columns ...
3
votes
2answers
1k 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
228 views

Import multiple files from folder in order of date added

I have a folder that contains certain files I want to import. In my case those are .png files. As all the files I want to import contain the phrase "accum" in their filenames, I can use ...
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
162 views

Why are dictionary keys reordered upon JSON import?

After importing a JSON file, Mathematica changed the order of the fields. For example, I downloaded a sample file from: http://api.openweathermap.org/data/2.5/find?lat=55.5&lon=37.5&cnt=10 I ...
3
votes
2answers
108 views

Importing multiple tables within a single file

Suppose I have a file with multiple tables, each separated by a line beak, like this: ...
3
votes
2answers
201 views

Import[] exception possibly caused by ToString[] behaviour which I cannot explain

Let me just start by pointing out I'm a new StackExchange user as well as a new Mathematica user (started today!) I mention this as a context to my ineptitude :) I am attempting to read through a ...
3
votes
1answer
161 views

How to sample n frames from a movie file?

I'm looking to import 100 image frames from an mp4 video file at roughly evenly spaced intervals. As $ImportFormats shows, Mathematica can handle Movie files: .avi, .mov, .qt, .flv Multiframe ...
3
votes
2answers
78 views

Manipulation of .csv imported data — no blanks in either of two lists

Above is a .csv file. I am trying to construct two lists of male and female math test scores such that only districts which include info for both male and female students are included i.e. neither ...
3
votes
2answers
246 views

Mathematica data structures for analysis [closed]

I'm starting to learn Mathematica and one thing that has been bugging me is the apparent lack of a good structure for keeping data and metadata for analysis. Something along R's ...
3
votes
1answer
350 views

how to delete specific data from text file and then update it

I have a large text file. I read data from text file one at a time and check whether data agree with my condition. If not I want to delete that data in text file and update it. For example say my ...
3
votes
2answers
413 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
325 views

Exporting lists to files

I am trying to write a program which will generate a list of objects and then exports it in a separate file and clears its memory. As an example I tried the following ...
3
votes
1answer
273 views

Easiest way to parse semi-structured text file

I have a plain text file with some data. I need two things: Be able to extract certain values for the various field, e.g. to extract the 'Mean Dose [%]', that is to extract number ...
3
votes
2answers
195 views

Lookup in Inverse Symbolic Calculator+ from Mathematica

There is a useful feature in WolframAlpha that allows to find a possible closed form for approximate numeric values. It can be used, for example, to guess the value of an integral that Mathematica ...
3
votes
1answer
305 views

Plotting with ColorFunction -> GrayLevel - no black

This is probably a fairly trivial question, yet I have been unable to find an answer - help would be much appreciated! :) I am trying to plot a 28 x 28 matrix (tabulated data given here), containing ...
3
votes
1answer
836 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
76 views

How to import several files at once?

I tried to import multiple files at once. Following this topic my code is ...
3
votes
2answers
90 views

Most efficient way of splitting a file into length-prefixed blocks

Let's say I have a really big file (>100MB) that consists of length-prefixed blocks, i.e. the first byte of each byte block indicates the length of the rest of the block. This is a simplified example ...
3
votes
1answer
186 views

Using the variable in the MATLAB workspace using MATLink or any other packages

I have a program in MATLAB and after I run the program, I get some results in MATLAB's workspace. Now, I need to use these results in Mathematica. What I currently do is that I save the workspace as a ...
3
votes
1answer
238 views

Importing numerical values from a PDF file

I need the numerical values from pdf files like this one. When I use the usual Import command, the PDF imports, but pages of images. How can Mathematica be used ...
3
votes
2answers
146 views

how to convert string output into executable commands

temp = (layer = #; layerS = ToString[#]; StringForm["Import[\"drainCdg_gdat0``\",\"Table\"]", layerS]) & /@ {1, 2, 3} how to get the output of ...
3
votes
1answer
625 views

Read and filter a text file without importing

I have a large text file of a million sections. Each section contains A lines of header and B lines of numeric data. I want to read the first and last line of B from each section (to have a list of 2 ...
3
votes
2answers
262 views

Since installing mathematica 9 I can't import certain tiffs

I have a notebook written in Mathematica 8 in which I imported Tiff images and everything worked fine. Since I installed Mathematica 9, I get the error: ...
3
votes
1answer
258 views

Efficiently importing XPM matrix data into Mathematica

The XPM file format is an image file format. Although it is primarily intended for icon pixmaps, it can also be used to store matrix data. For example, the GROMACS chemical simulation package uses ...
3
votes
1answer
52 views

How to force Mathematica to interpret a file as HTML?

Some web pages do not explicitly contain the file extension "html" but is formatted that way (like this one). If I saved this page to my computer then Mathematica could parse it correctly. But if I ...
3
votes
1answer
197 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 ...
3
votes
1answer
560 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
151 views

Reading many single files and creating numbered (? or indexed) variable

I tried many different approaches, but I could not solve the following problems, I appreciate your help: What is the best way to read many data files? I mean we have ...
3
votes
1answer
150 views

Reading RData files without RLink

I am using Mathematica 8. I would like to read some RData files which I have received. I do not currently have an installation of R on the machine with Mathematica.
3
votes
1answer
648 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
1answer
88 views

Problem exporting and re-importing STL file

I wrote all code and there're no errors in code. Result of code is like first picture(left). But I can't Import that structure. The result of import stl file is second one(right one). How can I import ...
3
votes
1answer
82 views

How is Precision of Imported Data managed?

I am working on a financial/banking type application and part of the work is to import numeric data of 15 to 20 digits of precision. I am having trouble determining the best way this should be done. ...
3
votes
2answers
318 views

How to delete all rows in datafile that contain a string

I'm importing some data from a file. However, the file was created by an unreliable instrument, such that the data looks like this: ...