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
97 views

How to get sub property from json result?

I'm brand new to Mathematica and I imported a json: data = ImportString["{\"x\":1,\"y\":1}", "json"] and result: ...
2
votes
0answers
90 views

Using SHP files to draw a density map [closed]

My SHP file of census block groups has polygons and associated employment data for each block group. Is there a simple way to draw an employment density map? I've played around with ...
11
votes
3answers
1k 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: ...
11
votes
2answers
1k views

Stream CSV or TSV files

RAM limitations make import impractical for large CSV files. Is it possible to Stream CSV correctly? str = OpenRead["EU.csv"]; Read[str, "CSV"] Read::readn: ...
3
votes
2answers
105 views

How do I run 1-855 data points( imported from excel sheet) into a formula to obtain value for each data point?

I am very new to Mathematica and I just couldn't figure out the solution for the following problem. I have two columns in an Excel file. I have imported the 1st column as ...
10
votes
1answer
120 views

Converting text from unsupported encodings like 866 into known by Mathematica?

The list of character encodings currently supported by Mathematica is still extremely limited. For example, it supports only three standard IBM PC (OEM) code pages: ...
1
vote
1answer
79 views

How to get missing lines from a file? [closed]

Let's say I have this file dat.csv which basically is a number of strings like that: animal horse duck dog plant tree grass sunflower sky oxygen nytrogen air ...
6
votes
0answers
76 views

Can't get Mathematica to Import PDF files with diacritics on the file name

Tested with versions 9.0.0, 10.0.2 and 10.3.0, all under OS X 10.10.5. and Linux The drag-...
0
votes
2answers
56 views

Assigning columns of data from a file to variables extracted from headers

I'm very new to Mathematica. I want import a file in which the first colum is a function f1, the second another function f2. So the file looks like this: ...
3
votes
3answers
327 views

URLFetch functionality for a Persian website

I want to fetch the content of a Persian website. I tried URLFetch["http://www.tsetmc.com/"] Why is Mathematica unable to recode the characters in the results ...
1
vote
1answer
102 views

Export the coordinates of STL object

Hi I currently have a STL file of a 3D object Is it possible for me to obtain the coordinates of the object so that I can just input that into Autodesk Inventor
0
votes
1answer
75 views

How to convert this .txt data into a list of points [closed]

Question How to import data from a .txt file into Mathematica and convert it to an expression? Download the .txt file here (click download): http://pastebin.com/2NW2DfiE
0
votes
1answer
76 views

Why vertices number increased when importing .STL file

I import a .STL Import[*.st,"VertexData"] file on mathematica and I remark that the number of vertices is increased comparing to the number given by Blender. ...
9
votes
3answers
455 views

Why doesn't DumpSave work for elements created within a local notebook context?

I recently noticed that when dealing with notebooks with local context, I cannot successfully DumpSave variables, or, rather, when I call ...
3
votes
2answers
956 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
1answer
71 views

Reading an exported List

I have exported a list of 2d coordinates as a List: Export["F:\\coordinates.dat", coordinates, "List"]; You can access the ...
1
vote
0answers
42 views

What is a good way to import interpolating functions of large size? [duplicate]

I was generating a set of eigenfunctions from a differential equation using NDEigensystem. Because of the computer time cost is too high, I thought it'd be better ...
0
votes
1answer
76 views

Applying a formula to the data in several files [duplicate]

I am calculating with the depth data recorded in a number of files with extension .log. The depth data is like this and I loaded it by means of Mathematica: ...
2
votes
1answer
53 views

read Python-generated data file

I've read similar-but-not-quite-the-same questions : I have to read a python-generated data file which contains complex numbers. So, the numbers appear as (real+imag j). And of course Mathematica ...
2
votes
1answer
245 views

Import 'file not found' error. Why? [closed]

I'm trying to import a file, and for that I'm using the following code: ...
1
vote
1answer
51 views

Trying to get simple excel data to be imported as a social network directed graph

My data has two columns that we'll call A and B. The columns proceed as such A B A1 B1 A2 B2 A3 B3 .... I'm trying to make this into a directed graph where A1 has an outgoing edge to B1 and ...
2
votes
2answers
265 views

Follow each pixel brightness in set of images (Memory constrained)

I have a set of 2700 consecutive png images (8bit, 2048*2048 pixels). I would like to visualize the intensity variation of each pixel vs. image number. Here is an example of 10 images: http://goo.gl/...
-1
votes
4answers
180 views

Import vs ReadList CSV file with Currency Values

A testing file with the specified format can be downloaded from here Let's read a few lines from this file ...
3
votes
2answers
191 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 ...
5
votes
2answers
266 views

Max of imported numerical data will not work

I loaded a list with 400,000 values from a file. The list was loaded correctly as I can get it's length (by Length[]) and I can also plot it. Why can't I get the Max or Min of this list though? When ...
0
votes
1answer
84 views

SocialMediaData[“Twitter”] - strange output

I am getting error messages when I use SocialMediaData["Twitter"]: ...
5
votes
1answer
115 views

ReadList ignore comment lines?

Is there a way to make ReadList ignore certain "comment lines" (say, all lines that start with #, or in general all lines that ...
6
votes
1answer
439 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
2answers
81 views

How to separate the double columns while reading file

I have a file which has contents of the form 10533 "MENDOZAT " 115.0000 : 1 1.00000 Now I want to separate the words and get it as a list. like ...
4
votes
2answers
227 views

How can I encrypt/decrypt a directory?

I'd like to use Mathematica 10's new Encrypt and Decrypt functions to secure files and folders on my mac. Here's what I have so far but something goes wrong along the way, since by the end of this ...
5
votes
0answers
122 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 http://www.wolfram.com/data-...
1
vote
2answers
126 views

open Matlab sheet and plot

I have managed to import my data into mathematica, but I can't find a way to show the plot the way it was in the lab (Matlab automatically generated file usually show me a graph). Is there a way ...
1
vote
0answers
67 views

Import Excel data from within Manipulate

I am processing a set of data using Manipulate, as I need some user input as well and the whole code must be delivered as .cdf . The set of data should be imported from an Excel file which is selected ...
6
votes
0answers
134 views

Call Magma in Mathematica

I've written some code in Mathematica, related to some group theory questions I have. Subsequently, I found that part of the code could be significantly sped up if I could just call a routine in ...
2
votes
1answer
81 views

how to import plain text file, with mixed formats with strings that contain commas [closed]

I have been struggling with this basic task, and I am surprised it is this hard to do in Mathematica. I get lost in the maze of Import and options and sub-options and after trying many things, still ...
5
votes
3answers
383 views

Histogram of a very large dataset?

I have a very large dataset stored in a file (over 2GB). The file contains a tab-separated table of floating-point numbers. I want to do an Histogram of all the numbers in the table. But if I try to ...
1
vote
0answers
415 views

Import/Export a FIT file, Fitness file created by Garmin GPS's and others

A FIT file is a binary replacement for GPX and TCX text files containing GPS and fitness data (heart monitors, etc.). Mathematica reads GPX and TCX files and represents them as XML. I would like to ...
3
votes
1answer
158 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 ...
6
votes
1answer
139 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. ...
0
votes
3answers
85 views

Importing Text file with Null Character column separation

I have a text file (ANSI econding) with two columns of real numbers separated, unfortunately, by a "Null Character" ("\.00"). How can I import this data easily? ...
18
votes
1answer
1k views

Slow import of multigigabyte TIF image stacks

Update 6: After contacting Wolfram Technical Support, I was advised that the frame-to-frame import timing variability can be eliminated by reading in the frame stack from frame to frame with the ...
3
votes
1answer
117 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 ...
1
vote
1answer
100 views

Using ReadList to import specific arrays of a multi-dimensional variable

Consider a large numerical variable (almost 1GB) which was constructed like below: output={scalar1,{Matrix1,Matrix2,Matrix3,scalar2}}; I used ...
8
votes
1answer
200 views

CloudDeploy - Import[x] issue

My question is about why Import executed in Wolfram Cloud with a fixed value (see A) works and with a variable (see B) doesn't when you use the form and submit the value 5565471199 (same as the fixed ...
2
votes
1answer
105 views

How can I run my API on an image?

I've built an API that takes a url of an image as an argument. Using Import[] I can easily call my API on any url and get the results... but I need to run it on an ...
6
votes
3answers
504 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 ...
0
votes
1answer
87 views

Package to read in data from excel files

I want make a package to add a function to Mathematica that reads all excel files is the working directory that is set after the package is loaded. ...