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7
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0answers
111 views

Median of Dataset in Mathematica 10

I'm having trouble calculating the median of a Dataset[] in Mathematica 10. The situation is as follows. Consider a dataset that was defined as follows: ...
3
votes
0answers
98 views

External file Sub Matrix Import

Is there a Built-In Mathematica Function to extract a Sub matrix from a huge external file? Functions getting pieces of internal nested Lists, (arrays) are in place. Example: ...
3
votes
0answers
246 views

How to save (large) data generated from simulations

The following is a simple example of a much larger simulation that I want to run Define some processes ...
2
votes
0answers
157 views

Lazy evaluation/loading of parts of an expression

Is it possible to have an expression x such that its elements are only evaluated when they are individually accessed, for example when evaluating statements like ...
2
votes
0answers
166 views

Exporting Specific Cells of Many Workbooks into One using Mathematica

I currently have a large number of detailed files from which I would like to extract certain cells' information to make an Archive spreadsheet. There are approximately 9 parameters of each ...
2
votes
0answers
96 views

Significant platform-dependent efficiency when importing data?

I'm curious, as I understand that answer this way: If you are using a Linux derivative or something like cygwin on Windows, then this is an efficient solution for reading only the third field ...
1
vote
0answers
70 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 ...
1
vote
0answers
44 views

Historical Prices via FinancialData

I downloaded the historical stock prices for some stocks in the period 1990-2013 via FinancialData some months ago and computed the financial returns. Now I downloaded the data again for the same ...
1
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0answers
405 views

Doing local FFT on huge 3D vector data cell mesh and visualizing it spatially?

Simulation type: I'm running a simulation with the OOMMF micromagnetics package http://math.nist.gov/oommf/ where are magnet is represented by a mesh of 3 million cells, it gets excited by a ...
1
vote
0answers
91 views

ReadList and multiple access of the same file

I have a file containing a large amount of data which can be processed independently. In order to process all data in a reasonable amount of time I distribute the jobs on three different machines. ...
0
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0answers
90 views

Spectral Clustering

I am interested in the following question: How is it possible to check whether an algorithm is working properly? However, this question is too general for the post and I'd like to restrict attention ...
0
votes
0answers
45 views

Creating ODBC connection on mac

Iam not able to create a ODBC connection on mac through mathematica even though i have created a connection successfully through ODBC Administrator. The error message iam getting was: JDBC::error: ...
0
votes
0answers
55 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
54 views

Discrete Fourier Transform and data manipulate

I solve a system od ODE and i save the discrete solution (i.e.: x,y,vx,vy, or a subset of it) in a file. Then i try to call the DFT on this file but the problem is that i must have also the time in ...
0
votes
0answers
192 views

histogram fit for probability density

I am trying to fit the (probability density) histogram of some data with the exponential function, but I am having difficulties. My raw data are in file called ...
0
votes
0answers
267 views

Performance in parameter estimation from ParametricNDSolve using varied initial conditions

I have 250 data points from a timecourse exeriment in a list, with columns specifying (1) time, (2-4) initial conditions, (5) absorbance reading. I want to fit 4 parameters (k1, k2, k3, k4) in a DAE ...
0
votes
0answers
96 views

How to combine file data chronologically via reading numbers in a filename and put it in one list?

Say I have a bunch of files with nearly same filename, eg. data_timestep1, data_timestep2, ... The data itself in one file is ({x1, y1, z1, absolute field value 1}, {x2, y2, z2, absolute field value ...