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
162 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 ...
10
votes
1answer
370 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
94 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
235 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 ...
21
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
64 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
237 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
178 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
430 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
298 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
413 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
181 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. ...
19
votes
1answer
546 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
404 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
144 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
33 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 ...
1
vote
2answers
101 views
9
votes
1answer
545 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
413 views

Importing web page data

I tried importing a webpage using Import: ...
5
votes
2answers
376 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 ...
1
vote
1answer
95 views

ReadList error with negative very small numbers

When I try to import data with ReadList from a file containing very small numbers (~10^-318), positive data is handled well, ...
4
votes
1answer
893 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: ...
5
votes
1answer
279 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 ...
0
votes
1answer
256 views

Importing data to make a DateListPlot

I am having a hard time trying to import some text data for later use in DateListPlot. My first field in my data is a date of the format "yyyymmdd". I tried to ...
2
votes
1answer
198 views

Saving a graph of a great number of nodes

I'm developing a code where I get graphs with over 10K nodes. These graphs have a particular relationship between clustering and degree that I need to save for future analysis. The problem is when I ...
1
vote
1answer
122 views

Extracting Imported Information

What I want to do is to compare the relationship between the consumption of say beer and wine using scatter plots where each point designates the particular country (preferably named). I have tried to ...
5
votes
1answer
224 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
1
vote
1answer
500 views

Import invocation fails with Get::noopen : Cannot open JLink error

The following function call fails when I invoke it in a fresh Mathematica session: ...
1
vote
1answer
94 views

Using imported data in further calculations

I have quite a lot of data in an Excel file, which I have to use in further calculations. The transformation should map a data point with thre coordinates into a two coordinate result. Example: ...
1
vote
2answers
167 views

Problems with importing a .txt file

I have some problems with importing a .txt file as a table. This is the file. I tried importing it with data = Import["data.txt", "Data"] I want to access ...
3
votes
2answers
115 views

Importing multiple tables within a single file

Suppose I have a file with multiple tables, each separated by a line beak, like this: ...
9
votes
2answers
289 views

Working with Java hashmaps from Mathematica

I'm using J/Link to access data from an external Java program. The data are represented as a ConcurrentHashMap (see the official specification here). ...
3
votes
1answer
182 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 ...
8
votes
2answers
348 views

Problem importing a JCAMP-DX mass spectral file

I have some problems importing a JCAMP-DX EI-mass spectral file using Mathematica 9. For example, if I download the mass spectrum of nonacosane in JCAMP format from NIST, ...
3
votes
2answers
282 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: ...
12
votes
3answers
4k views

Excel Headers --> Mathematica

I have a large Excel .xls file. Miniature version shown below: (formatting should appear as two columns...) ...
0
votes
2answers
433 views

How to get the associated popup menu?

I have threePopupMenu and they work in such a way that second PopupMenu value depends on the value selected by the first ...
23
votes
3answers
2k views

Reading periodic elements from a large file

I have a large binary data file (big endian) with 100+ million "rows" of 11 elements, combination of floats and integers. This is the format: ...
4
votes
3answers
232 views

Reading binary strings from file as strings

I have a file that contains binary strings like 01011 00101 01011 I want to import the file to Mathematica as a list of strings, but ...
5
votes
4answers
2k views

Numerical Differentiation using 1500 data points

I have a set of 1500 data points (which are some energy eigenvalues) corresponding to a parameter H0 (which represents magnetic field. H0 values are equispaced going from $-3.0$ to $3.0$ in steps of ...
0
votes
1answer
1k views

Plotting Surface Graph from Excel Data Import to Mathematica [duplicate]

I am trying to make a surface graph on Mathematica using Excel Data. My x-axis should be the "A" Column and my y-axis should be the "1" Row. The box of data in between the x-axis and the y-axis should ...
2
votes
1answer
191 views

Is it possible to take data from external database for the CDF embedded in webpage?

I have embedded my CDF in facebook.The data for the CDF should be taken from facebook server or my server dynamically.I tried out but its not working in dynamic code iam not able to access the data at ...
0
votes
0answers
61 views

Importing and running a notebook [duplicate]

I have a very long .nb file. I want to subdivide the different sections into separate notebooks, then call them in a common nb ...
6
votes
2answers
731 views

Change character encoding for file read using OpenRead

I have a large bzipped file that I want to read using OpenRead on a pipe with UTF8 encoding. Doing the following does not give me UTF-8 encoding. My ...
1
vote
1answer
313 views

Alternating Axis Labeling between Left and Right Axis

I'm using the following to label a MatrixPlot: FrameTicks -> {{yticks, None}, {None, xticks}}, I'm labeling these ticks with text. It is impossible to get the ...
2
votes
1answer
269 views

importing large data files with a constraint

As I have learned in this community, one way to import a hefty data files (e.g. millions of rows of {x1, y1} data) if you don't care about the individual elements (maybe just want to obtain some ...
2
votes
2answers
560 views

ReadList and Import cannot read data separated by “,” [closed]

I have a data file contains several lines of numbers that separated by "," and I cannot load it correctly with ReadList and Import. Here is a example: with data contains "," and "\n", simple ...
0
votes
1answer
370 views

3D Plot of .txt File of the Surface Plotting Variety

I'm having a bit of trouble. I've seen other questions answered on here about how to 3D plot data from .txt files of the format: x y z x y z x y z Which works ...
2
votes
2answers
427 views

import a list of replacement rules

I have a text file with a set of replacement rules, of the form x^3y^2 -> 4, xy^2 -> 2, ... for example. I'm having some issues trying to figure out ...