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1answer
102 views

ReadList or any other command to read in blocks of very large numbers

I have a data file, data.txt, having following data: ...
8
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0answers
161 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: ...
6
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0answers
150 views

Implementation of Partial Least Squares (PLS)?

I'm looking for a PLS implementation for Wolfram Mathematica. I just cant seem to find any implementation for it - do you know one? In general, I'm a bit confused that there exist only so few ...
5
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0answers
83 views

Dropbox datastore

Dropbox seems to have a feature where it can be used as a database. This would be really cool to use for memoized functions, that can be restored on several computers and sessions. I have a function ...
3
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0answers
75 views

How to efficiently read data from any part inside huge file

I have a data file (over 2.5 GB) and I want to do calculations on the data. At first I used. data=ReadList["file", Record,n] I still have three problems: 1- ...
3
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0answers
197 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 ...
3
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0answers
104 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
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0answers
277 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
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0answers
78 views

Cloud cover fraction

I need to make use of Mathematica's WeatherData functionality, the CloudCoverFraction property, specifically. However, it does ...
2
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0answers
272 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
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0answers
104 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
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0answers
88 views

Using Periodogram to investigate the seasonality of the data

After asking how to get rid of the seasonality of this set of data, I'd like to ask how to investigate the seasonality in data using Mathematica. Which tool would you use to study seasonality? I.e. ...
1
vote
0answers
103 views

Taking a derivative, then squaring a two dimensional numerical function

Context I am interested in first finding an interpolating function of the solution to the linearly damped wave equation. Here is the solution to the LDWE with smooth square inital function : ...
1
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0answers
94 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
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0answers
71 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
503 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
98 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
59 views

System stochastic nonlinear differential equation, Ito process?

I'm trying to solve a system of nonlinear stochastic differential equation. It is a discrete nonlinear schrodinger system of n equation, with n independet weiner process. I'm actually using the Ito ...
0
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0answers
19 views

Binomial Regression where n > 1

I am not well versed in Generalized Linear Models, but am trying to use this approach to model some discrete data. I have binomial data where the sample size for each observation is the same size, ...
0
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0answers
51 views

How to determine if a point is within a geopositioned RegionMember

I have a KML file which contains an area of interest, I also have a number of lat/long geo positions. I'm trying to filter out the points not within my AOI. So I have my KML file. I convert it to a ...
0
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0answers
155 views

How to open *.sif files with Mathematica

While I am processing my data collect from an Andor EM-CCD, I find it diffcult to import the file into mathematica. I think mathematica can open this kind of files since that Matlab can open it. So if ...
0
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0answers
58 views

Convergence Problem using FindFit

I have the following input where there is a convergence problem in the FindFit as shown in the attached figure.The figure shows 2 plots: one of the real data and the other of the fitted line. Any ...
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0answers
148 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
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0answers
57 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
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0answers
66 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
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0answers
90 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
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0answers
458 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
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0answers
333 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 ...