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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0
votes
0answers
37 views

load NOAA ENC s-57 chart?

Is it possible to load a NOAA ENC s-57 formatted nautical chart into MMA 9.x? Particularly in MMA9.x within the MAC OS? -There does not appear to be any discussion of importing nautical charts ...
4
votes
2answers
71 views

importing a 150 MB .wav crashes Mathematica

rawdata = Import["rawdata_10min.wav"] crashes Mathematica when the file is 150 MB, but does not crash Mathematica when the file is 20 MB.
2
votes
2answers
578 views

How to Flatten and stack Efficiently 50000 Images

I have 50000 grayscale images with 56*56 pixels each one. I need to flatten images and stakck it in the same array with dimensions 50000*3136 after that export the file as .CSV. I am doing this code ...
1
vote
1answer
66 views

How to interpret and extract the information from the JSON (JavaScript Object Notation)? [closed]

How to interpret and extract the information from the JSON (JavaScript Object Notation)? I would extract the information and plot the information graphically. Please advise and comment. Thank you. <...
3
votes
1answer
33 views

Skipping commented in a stream from OpenRead

Is there a solution to skip comments in text files that are imported with OpenRead? I know there are solutions for Importand <...
0
votes
1answer
45 views

How to analyze a large wav file?

I have a large wav file (100 Mb). Any operation on it is time consuming. For example, to Import it takes about 1-2 minutes. The next step seems to be to figure out how it is encoded, since WAV files ...
0
votes
2answers
84 views

How to make a graph form imported spreadsheet data [closed]

I've three csv files: v.csv for vertex data, like this: 1 2 3 ... e.csv for edges: 1,2 2,4 2,24 3,1 ... and vcoor.csv for vertex coordinates: 23.4, 35.2 23.4, 40.3 ... I know how to construct a ...
2
votes
1answer
83 views

Change bond cutoff distance when plotting .xyz files

When plotting a molecule from a xyz data file, Mathematica automatically adds the bonds between the atoms. But in my case it adds too many bonds, not only between nearest neighbours but also between ...
1
vote
1answer
82 views

Cannot import PDF with JPXDecode or JBIG2Decode Filters?

I am trying to what I think should be a very basic thing, which is to import a large PDF from my files into Mathematica. The long term goal is to extract images from the PDF. The original command was ...
0
votes
1answer
58 views

Combining first 5 columns from CSV file into AbsoluteTime date

Thanks in advance for all your help. I need to import data from a CSV file that looks like : (easier to read in excel) I would like to convert the data into timestamps by creating a Table with 2 ...
0
votes
1answer
51 views

Improving performance Importing Table

I am currently working on mathematica script on a Raspberry Pi, which will periodically (10 secs) be launched by a bash script. However the runtime of my script really isn't the best. It's actually ...
2
votes
0answers
83 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 ...
7
votes
2answers
232 views

Extracting and displaying data from GW150914 hdf5 files

Has anyone looked at the LIGO data using Mathematica or know how to do this? I'm not familiar with the hdf5 format but I've been able to import the data, consisting primarily of 131,072 floating ...
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 ...
1
vote
1answer
78 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 ...
0
votes
2answers
55 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: ...
2
votes
1answer
60 views

Order of importing data from files

I have many text files numbered from 1 to 1 million in numerical order. Within each text file is 5 columns of data (TAB spaced) with many rows. I effectively want to take the minimum value from each ...
1
vote
1answer
93 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
74 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
3
votes
1answer
69 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 ...
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: ...
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 ...
2
votes
1answer
49 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 ...
0
votes
1answer
81 views

Importing $\LaTeX$

I have a LaTex file, and import it this way: tex=Import["texfile.tex"]; Now according to Help, this returns a notebook expression: ...
2
votes
1answer
213 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
49 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
262 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
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4answers
173 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 ...
5
votes
2answers
263 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 ...
5
votes
1answer
107 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 ...
5
votes
0answers
74 views

why does ReadString[“fname”,term] open a persistent stream, and how to close it?

Bug introduced in 10.0 and fixed in 10.3.0 Create a file temp.txt with the following content: test1 ;;; test2 ;;; test3 ;;; ...
5
votes
0answers
120 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
122 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 ...
4
votes
2answers
222 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 ...
1
vote
0answers
66 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 ...
3
votes
2answers
207 views

How to import 12-bit TIFF image

I have a CMOS camera which records images at 12 bit resolution. The camera software allows to save them as 12-bit TIFs. However, Mathematica cannot import this: ...
4
votes
1answer
91 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: ...
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
75 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 ...
3
votes
2answers
183 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
3answers
357 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 ...
6
votes
1answer
134 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. ...
3
votes
1answer
156 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 ...
0
votes
3answers
81 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? ...
3
votes
1answer
113 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 ...
6
votes
2answers
152 views
0
votes
1answer
75 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. ...
0
votes
1answer
86 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. ...
0
votes
1answer
41 views

Import a 3D CSV file results in the wrong dimensions

I exported a some of my data to a file, the data looks like this before the export ...
1
vote
2answers
163 views

Plot from data containing “e”

I have data as a "dat" file exported from matlab in this format: ...