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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5
votes
2answers
387 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
100 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
969 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
305 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
264 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
202 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
125 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
246 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
534 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: $(r,g,...
1
vote
2answers
168 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
117 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
295 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
186 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
360 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, http://webbook.nist.gov/cgi/...
3
votes
2answers
302 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
453 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
233 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
3k 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
196 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
63 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
776 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
332 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
276 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
599 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
382 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
471 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 ...
10
votes
2answers
595 views

Look up info associated with a given CAS chemical identifier from the NIST webbook & NCI CADD Chemical Identifier Resolver

I would like to retrieve information associated with a given CAS registry number (Chemical Abstracts Service nr) from the NIST webbook web site in Mathematica, using the provided API (e.g. for ...
2
votes
1answer
114 views

Problem with importing a JCAMP-DX IR spectrum file

I wrote a little function to import JCAMP-DX electron ionization or mass spectral files from the NIST webbook web site (e.g. mass spectrum of hydrogen chloride at http://webbook.nist.gov/cgi/cbook.cgi?...
6
votes
2answers
697 views

How to import a “.numbers” spreadsheet?

Does Mathematica support importing a ".numbers" spreadsheet file (from the "Numbers" '09 (ver. 2.3 554) spreadsheet program in Apple's OS X iWork office suite)? A ".numbers" file is actually a zip ...
4
votes
0answers
199 views

Single image import from stack via FTP connection

Background I would like to create a CDF document that is embedded on a webpage. The CDF will contain some image display ...
11
votes
2answers
3k views

Speeding up Import and Export in CSV format

I am handling large numerical data in Mathematica. In smaller problems everything worked fine using Export and Import with the ...
0
votes
1answer
189 views

Combining an imported PDB file with a set of Graphics3D objects

Imagine we import a PDB file like so (using the example from ref/format/PDB in the help directory): ...
2
votes
2answers
123 views

How to extract data depending on Position of First zero?

I have a file (attached as an image) which I imported to Mathematica and only extracted the first and second column. My problem is that I want to extract the data beginning from the row where $A=0$. ...
3
votes
2answers
420 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: ...
1
vote
2answers
291 views

Importing numerical data from RTF file

This might be a very simple question but I have been struggling with it for a couple of hours, so thought maybe someone here can show me a quick way of solving it. I have a file in rtf format (...
3
votes
2answers
278 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: ...
2
votes
0answers
72 views

The “right” way to define a custom Encoding format?

I have implemented an Import|Export format for xz that behaves like gzip and other encoding formats: ...
1
vote
0answers
83 views

Getting InputStream errors when including a call to ElementData within an Import definition

So I am writing an ImportExport converter for a common chemistry file format, and I've run up against a problem that seems to be about shared streams and whatnot. ...
5
votes
1answer
764 views

ReadList can't read from file containing high-precision Reals

I want to read a file which contains seven columns of real numbers. Mathematica seems to have a problem with the high precision I need. My code: ...
4
votes
1answer
183 views

Import audio in uLaw format?

How do I import a uLaw-format audio file into Mathematica? Here's an example: hello-world.ulaw For reference, here's the same file in wav format: hello-world.wav As I understand it, the uLaw ...
6
votes
1answer
742 views

Failing to import an .eps file

I have an .eps file which was created using GLE. There is nothing wrong with the file, GS View can read it correctly. However, when I use Mathematica to read it using ...
4
votes
2answers
176 views

Workaround for Import not supporting the \leqslant TeX macro

$\{A\leqslant x\leqslant B\}$ Copy the code into Notebook, and you'll lose the less sign, this can be rendered well in ...
3
votes
1answer
437 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 ...
1
vote
2answers
400 views

Import image using InputField and Button

I've got a pretty basic problem, which is probably easily solved, but for all my efforts I haven't found a solution yet: I want to make an Image importer of the following form: An ...
3
votes
1answer
1k 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 ...
7
votes
1answer
584 views

Importing DICOM images

When I try to Import individual DICOM (.dcm) files from http://www.osirix-viewer.com/datasets/ datasets I can see the Elements listed in example files, ie: ...