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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3
votes
2answers
114 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
211 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
228 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
84 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
276 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
2answers
261 views

How to read non-standard-format data into Mathematica from a file

I would like to read non-standard-format data into Mathematica from a file. How can this be achieved? For example, how can I read the following text file of data into Mathematica: ...
3
votes
1answer
390 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
442 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
356 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
2answers
121 views

Take a specific part of a matrix imported from a .xls

i would like to know if there are any ways to link headings of a table i had imported with the data in the table itself. I imported a matrix from an excel file and i want to take a specific part of ...
3
votes
1answer
94 views

How to import several files at once?

I tried to import multiple files at once. Following this topic my code is ...
3
votes
1answer
396 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
1answer
377 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
925 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
2answers
125 views

Importing CSV with multiline text fields

Here is a valid CSV: a1,b1,c1,d1,"e1 e1 e1" a2,b2,"c2 c2 c2",d2,e2 It has two rows and five columns, and contains two fields with embedded CRLF. (See the CSV ...
3
votes
1answer
123 views

Import a table from a text file or string

XYScan produces results in the following form (as *.txt): ...
3
votes
2answers
98 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
295 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
154 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
690 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
277 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
280 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
131 views

RawJSON vs JSON format

It has been very recently, since the release of version 10.3.0 I think, that Import/Export and ImportString/ExportString functions accept a format parameter with the value of "RawJSON". The ...
3
votes
1answer
82 views

Mathematica does not import .mat file correctly [closed]

I have .mat file that contains a binary (0,1) matrix with size 100*100*100. I have used this syntax to import it in mathematica ...
3
votes
1answer
55 views

Mathematica can't Import data of NetCDF file with Datasets name including “.”

I have downloaded NetCDF data file EVE_L3_merged_1nm_2015323_005.ncdf from http://lasp.colorado.edu/eve/data_access/evewebdata/products/merged/ and read it by Mathematica 10.0.2 on my windows 7. ...
3
votes
1answer
63 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
169 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
158 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
692 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
122 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
364 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: ...
3
votes
2answers
874 views

Importing data into an array, column by column

I'm building a large matrix having different sized rows consisting of a few columns. The different columns are imported .txt files. Why can't I build the matrix column by column? For example, I ...
3
votes
2answers
278 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
484 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. ...
3
votes
1answer
517 views

Importing file with UCS-2 Little Endian codification

I'm trying to import a text file with UCS-2 Little Endian codification but I can't read it correctly. There's any hidden option to read this files ?? I'd tried with ...
3
votes
3answers
670 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
1answer
361 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 ...
3
votes
1answer
172 views

how can i associate the headings of columns/rows with content of itself and then recall what i want after i've imported the excel file in mathematica

Hello, i make another try... I have to import a file like this below (it is an excel file, i show you just the beginnig. it should have thousend of rows and columns). After i've imported the file i ...
3
votes
2answers
77 views

Troubles importing date and time from CSV file

I'm trying to import CSV file with the following format: 20150803 00:00:01.649,1.09675,1.09678 using this code: ...
3
votes
1answer
326 views

Efficiently reading CSV with ReadList

I have a large CSV file (~1gb) with mixed data. Basically with strings and integers. It takes very long to import this whole dataset with Import[] so I would like ...
3
votes
1answer
282 views

How to make the plot from geotiff format

I have a "GeoTIFF" format map, and I have imported it into Mathematica, then I used the Graphics to plot a point on the map. ...
3
votes
1answer
498 views

Running external pdflatex command and importing the generated PDF document

There have been a couple of questions about incorporating labels and equations that were typeset in $\LaTeX$ into a Mathematica notebook. Ideally, this requires running ...
3
votes
1answer
636 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
107 views

Local evaluation works, CloudDeploy did not work

I a playing around with my programming cloud account. What I have found, interactive functions often are not working because there are several details that are not implemented into the cloud. So I ...
3
votes
1answer
92 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, ...
3
votes
1answer
101 views

Registering/detecting an importer by file name extension

I've developed an importer and exporter for FreeSurfer's MGH/MGZ file format; the specific format isn't important, but I was ...
3
votes
2answers
262 views

Import numeric data into Mathematica

I have a C++ program that outputs a set of numbers at each time step. A blank line separates successive time steps. Here is an example of my data format: ...
3
votes
1answer
271 views

Importing a ragged array while ignoring rows that start with “#” [duplicate]

I am new to Mathematica, and I find that there may be a lot of ways of doing this. I was wondering which one might be the most general. I am importing data from ...
3
votes
0answers
78 views

WDF specification?

Motivated by a recent question on the meaning of all sorts of W* acronyms, I would like to get more information about the Wolfram Data Framework (WDF). On its web page ...
3
votes
0answers
107 views

Importing large number of frames form Video - improved method?

I am trying to work with large numbers of frames from a video (30000+). I see there are a number of answers out there, but I find none of them satisfying - see below for details. I understand from ...