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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6
votes
1answer
396 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 ...
4
votes
1answer
283 views

How to clean up messy data

The start of my question is about one specific situation - I have some erroneous lat/long values in a dataset which I need to clean up. But I'd like it to cover the overall topic of cleaning up messy ...
2
votes
2answers
211 views

Overwriting first line of large file

As mentioned, I wish to read the first line of a file, and if needed, overwrite it with a new string. The aim is to have a CSV with a list of possible elements. Example: ...
4
votes
2answers
710 views

Check Google PageRank for a given URL

Does anyone know how to write a Mathematica function that returns the Google PageRank of a given URL? I found a tutorial for achieving this in a bash script here, but I have no idea how to port this ...
2
votes
1answer
74 views

How to read from /dev/random?

I am looking to read a few bytes from /dev/random on OS X and Linux. The simplest approach fails on both operating systems (see below). Why? What is a ...
3
votes
2answers
184 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 ...
32
votes
4answers
3k views

Importing videos in Mathematica

Mathematica's Import command is purportedly able to import .AVI files. However, I find that many files that I want to import do only result in MMA showing a blank ...
15
votes
1answer
320 views

Why does ImportString[“1c”, “Table”] eat the letter c?

I have some whitespace-separated matrix data that I read with Import[..., "Table"]. The data contained mixed strings and numbers (the strings are for row and ...
3
votes
2answers
214 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 ...
-1
votes
3answers
101 views

How do i import a list of files, choosing the name

I have this list of files, i'm using FileNames[{"*.txt"}, NotebookDirectory[]] to import it, but i just want the ones without inelastic on the name. How can i select just by the name? Thanks ...
4
votes
2answers
335 views

SemanticImport mis-interprets CSV

SemanticImport misinterprets rows with trailing blanks. Note the commas in the 2nd column: ...
0
votes
1answer
120 views

Loading and processing five files at a time from a directory containing many, many files

I have 3000 files (for example: aa101.csv, aa108.csv, aa120.csv, ...) and I need to process them. I need to load five files from a folder, process them, and export them to new list in Excel. Then I ...
3
votes
0answers
74 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, ...
1
vote
0answers
98 views

Datastream to Mathematica

I currently use data from Thomson Reuters Datastream. With an add-in in Excel, the data can be requested. Because I need to use the data in Mathematica, and I need to update the data frequently: Is it ...
2
votes
1answer
177 views

diff-able text-only notebooks?

I would like to save my Mathematica notebooks as plain-text documents, so that I can keep them under git version control. I thought that ...
5
votes
3answers
526 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. ...
2
votes
1answer
78 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 ...
6
votes
1answer
210 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 ...
4
votes
1answer
155 views

Importing malformed XML: Import[… “XMLObject”] vs ImportString[…, “XML”]

It appears that Import[ url , "XMLObject" ] is more forgiving of improperly formatted XML than ImportString[ string, "XML"]. For ...
6
votes
1answer
147 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] ...
5
votes
2answers
1k 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 ...
2
votes
2answers
101 views

Importing Data and Devoting Their Names to Them

There are some files in a directory. I have used of SetDiroctory to access all of them. SetDirectory["C:\\Users\\SE7EN\\Desktop\\mathematica\\test"]; I can visit ...
2
votes
2answers
61 views

How to prevent conversion of number forms to numbers in Import [ webpage, “Data” ]?

I have tabular data on a webpage. It looks like this: Import["http://mfvonh.me/numericalTable.html", "Plaintext"] 1.0 1.1 3.53 However, I have ...
0
votes
1answer
63 views

Importing colors from file

I just tried something straightforward (for me): ...
5
votes
1answer
305 views

How can I recover the source code from cdf file?

by a mistake I have deleted the nb file by which the CDF was generated. All required definitions were in one cell. If I remember the code looked like this: ...
0
votes
1answer
51 views

Importing a Matrix whit different column numbers depending on the row

I have a bunch of coordinates given in a file. The file contains Startpoints and Endpoints of arrows in columns(Example): ...
2
votes
2answers
155 views

Animation of moving rectangles in 2D from data file

I am not very familiar with mathematica but I know the basics so I thought I give it a try. For a project I have to animate rectangles moving around in 2D (later also 3D). The data come from a C ...
4
votes
1answer
93 views

Order imported files by their alteration date

Probably a very easy question, but I could not find the answer, so it would be very nice if you can help me: Let us say I have 10 files, all with the extension ...
9
votes
1answer
296 views

Wikipedia People only search

I am trying to search people from Wikipedia(For example .*John.* in REGEX). The following query is close, but it isn't generalized like ...
-1
votes
1answer
75 views

How to draw a network from a dataset reporting the labels of nodes of every link?

I have a dataset in format .txt of a directed network, containing a matrix A of dimension ...
0
votes
1answer
118 views

Importing a text file into a matrix format

I am attempting to perform a comparison of pseudorandom number generation with the RAND Corporation's "A Million Random Digits with 100,000 Normal Deviates" for a Computational Physics course. I have ...
18
votes
4answers
1k views

How to efficiently import videos

I need to do frame-by-frame analysis of videos. I can import the video files I need, but each file is too large to import at once. I can use the ...
0
votes
1answer
61 views

How should my data be formatted for use with BetweennessCentrality?

A few weeks ago I asked this question. I am trying to upload my data which is an adjacency list for an undirected, unweighed graph and find the betweenness centrality. At the time I tried to use the ...
0
votes
1answer
180 views

How do I upload a graph as an adjacency list and find the betweenness centrality?

I have an undirected simple graph in a .txt file formatted as an adjacency list like this: 100 200 200 300 300 400 500 600 700 800 900 ... Every number is a node ...
1
vote
1answer
109 views

Importing adjacency matrix from file of 0/1 arrays

Is it possible to import adjacency matrix for graph representation, from simple text file with NxN (rows x columns) of 0s/1s: 0 1 0 0 1 0 1 1 0 1 0 0 0 1 0 0
5
votes
1answer
338 views

windrose with data from Excel

How to Import data from excel and use them to Plot windrose instead? Example, {{Strength, Angle(degrees)}..} ...
1
vote
1answer
207 views

Import CSV with “Numeric”->True and “DateStringFormat” problem

The CSV file linked below has 3 columns: "PT_ID" (char 4), "PHYS_ID" (char 2) and "VISIT_START_TIME" (varchar eg "0:00:15" hours minutes seconds) ...
3
votes
1answer
284 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 ...
2
votes
1answer
149 views

Text analysis and loops

I need a loop for a text analysis involving about 1000 papers (identical structure of all papers) I have these two commands to read all the papers into memory. ...
16
votes
1answer
482 views

Gravatars/identicons with Mathematica

The default avatar/identicon is based on an MD5 hash of your e-mail address. With some e-mail providers (e.g., GMail) the address gmailuser+foo@gmail.com is still ...
2
votes
1answer
299 views

Importing data from excel and assigning a variable to each of its columns

How should I assign variables to the data imported from excel containing 3 columns which are time, mean and standard deviation. I want to perform operations on the three variables to get new ...
0
votes
2answers
80 views

How can I troubleshoot a PDF that fails to import?

I'm trying to import a PDF file whose text I'd like to parse, but I'm getting an error with no explanation: ...
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 ...
0
votes
0answers
71 views

How to save all data in all variables in context different than “global”?

I have seen questions on saving data on "global" context. Now if I set my notebook's evaluation context "unique to this notebook". the global context doesn't work quite well. Any idea what should i do ...
0
votes
0answers
32 views

relative directory paths within a mathematica package/what directory does a mathematica package see as local? [duplicate]

I have a package that gets loaded in many notebooks I use, with Import[pathToLibraryDirectory<> "toolkit.m"]; This toolkit in turn loads some Excel ...
8
votes
1answer
429 views

How to import a large (~50Mb) json file in mathematica

I am trying to import a 46Mb json file into mathematica (which by the way I exported using mathematica) but its failing with the following messages: ...
2
votes
1answer
214 views

Importing web page data

I tried importing a webpage using Import: ...
5
votes
2answers
275 views

Sorting a large file

I have some huge logs, which are text files, containing up to a million rows each, and I need them sorted. Because trying to import one obviously makes Mathematica run out of memory, we must rule out ...