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0answers
80 views

How to render a 3d image of the galaxy? [closed]

I recently came across the Uniview software package, there has even been a TED talk about it. Here is another example of some interactive views of star maps. In Mathematica 10 AstronomicalData has ...
1
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1answer
87 views
1
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2answers
102 views

Plot a bunch of lines in 3D from point data

I have a 12*25 array, wherein each entry is of the form $\{x,y,z\}$. So 12 different $x$ values, 25 different $y$ values and 12*15 $z$ values in all. I'd like to plot 12 curves of various $x$ values ...
0
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0answers
20 views

how can sent data to Mathematica and get result in java? [duplicate]

I try to develop an math script calculator in java. My script has advance math functions and I can't calculate them in java.(for example limit, plot, ... ) Is any way for sending script to ...
0
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1answer
29 views

Is there a limit for DensityHistogram data amount?

I'm trying Mathematica for first time and while trying to do a Density Histogram with around 300 000 points, I get an error "THE INPUTED DATA is not a valid dataset or list of datasets." Maybe it's ...
4
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1answer
78 views

Is Mathematica's (v10.0.2) NetCDF exporter broken?

I'm trying something very simple, namely: Export["file.nc", {"Datasets" -> {"seqs" -> {"AAA", "BBB"}}}, "Rules"] And getting Java errors about "illegal ...
2
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1answer
86 views

Finding periodicity of multidimensional data?

I have a data set consisting of measurements of an $n$-dimensional vector $\mathbf{x}(t)$, at $N$ distinct time points $t_i$. The time points $t_i$ are equally spaced. I need to find the dominant ...
2
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0answers
66 views

Cloud cover fraction

I need to make use of Mathematica's WeatherData functionality, the CloudCoverFraction property, specifically. However, it does ...
0
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0answers
18 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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1answer
48 views

How to fit this data to be used in NIntegrate later?

I have a list of data points that resemble a chi-squared distribution (long tailed gaussian) that I am having trouble fitting or finding an equation with. The goal is to use the fitted equation in an ...
2
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3answers
237 views

Import data from first/last 100 rows of a file

If one wants import data from the first three rows of a file "myfile.data", one can use the command Import["myfile.data",{"Data",{1,2,3},All}]; However, if I ...
0
votes
1answer
41 views

How to assign the array data to variables?

A very basic question but puzzled me for long time on how to assign array to variables. For instance, we have array {{t1,x1},{t2,x2}...{tn,xn}} how to assign the first element to variable t and ...
4
votes
1answer
98 views

Most efficient searching algorithm in a table

I am completely new in Mathematica (and in data analysis in general) and I find it really useful, although I still do not use it properly. I have the following question related to data manipulation: ...
6
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0answers
120 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 ...
1
vote
1answer
55 views

FindClusters memory exception problem in dealing with 1Dimensional data?

data=RandomReal[10,{30000}]; FindClusters[data,2]; Why in this little data set, FindClusters Load so much memory? and ...
1
vote
1answer
53 views

List Manipulation and Removing Cases

I've imported a large data set, manually removing headers in the .rtf file where it originates. However, when I import this data, I receive this output: ...
1
vote
1answer
72 views

FinancialData Input

What does the function FinancialData require as input for natural gas: http://finance.yahoo.com/q?s=NGG15.NYM Is it easier to export the natural gas data to ...
1
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2answers
178 views

How to obtain the best possibe NonlinearFit

Here is some sample data ...
5
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2answers
124 views

Building bounded polygon around heatmap (or points)

I have a set of data for world marine piracy. I'd like to build polygons encircling areas of active piracy. So to start with I get piracy data and make a heatmap from it. ...
22
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1answer
324 views

Visual representation of a Ranking over time (image provided)

[Disclaimer: I initially posted this question on stackOverflow 2 months ago and think it might be better suited for this forum (link to original question)] The graph below shows a ranking of ...
1
vote
1answer
54 views

Mixture coefficients and Parameter estimation for moving Normal distributions

I am searching for a way to do the following steps below. I am stumped and I have stumped a few profs too. Any help would be appreciated. I would like to import data from, say, excel or a .txt file ...
1
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1answer
93 views

ReadList can't read “.csv” data with correct line number?

Well, the problem was solved today. Since "testAll.csv" is generated by Java/Eclipse, and I noticed that the LineSeperator is ...
3
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3answers
166 views

How to detect outlier in data of an unknown function $f(x)$

Suppose I have an unknown function $f(x)$ that is monotonic, convex and nonlinear by definition. I somehow evaluated it at 1000 nonuniform $x$ points. By ploting these data, I found a very obvious ...
0
votes
1answer
78 views

Fitting data with inclusion of constraints

How do I find a fit for the dataS (see below) with the constraint that the parameter np is an integer, and that the parameters la+lc = 100. A weak attempt at this is provided below for a specific ...
5
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1answer
172 views

Forcing NonLinearModelFit through a point

Like the title says, is there a way to make an NLM fit pass through a specific point.
1
vote
1answer
119 views

Country density plot of lines (highways)

I love solution from question (histogram as well as distrubution) http://mathematica.stackexchange.com/questions/31948/show-density-plot-on-us-map#=. But both cases are a bit more difficult in my ...
0
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0answers
44 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 ...
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3answers
168 views

How to import files with headers?

R has excellent header supports such as read.table with header options. I don't want to mess up with text-processing or stream-processing. I am looking for a similar tool as in R because it saves a ...
2
votes
1answer
59 views

Statistical Analyzis of Observed Data (Queuing Process)

Basically I have a process that belongs to a certain state at any point of time. However, the time intervals are not fixed (in fact they are exponentially distributed). Essentially, the data points ...
1
vote
1answer
66 views

How to append data in an already existing data .txt file in newline or in tab separtion?

Say I have an already existing .txt file containing data in the following format. $a \qquad b$ Now at different times I will successively have data like ...
2
votes
1answer
68 views

Struggling with FindFit

I'm trying to fit a sinusoidal wave to some numerical data. I can do it by hand using manipulate, so I know roughly the sort of parameter values that I should get back, but functions such as FindFit ...
5
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2answers
137 views

Getting the Cumulative Distribution Function of f(x) from a dataset of x

I've a data set $\mathcal{X}$ which consists of randomly generated numbers. Let's say for example data = RandomVariate[ExponentialDistribution[1], 10^4]; My aim ...
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2answers
71 views

How do you (sanely) fix up data in a csv/table?

I have data in a CSV file I've Import[]ed. Some of the data needs fixing up - date formats changed, data normalized, etc. After fixing up I'll insert it into an SQL database. My CSV file has ...
1
vote
1answer
54 views

Export data from NDSolve when they meet a certain condition

I need to export to a txt file the data from the following system of equations: ...
0
votes
3answers
105 views

Importing multiple files with a loop

I have 101 files with data that I want to import into Mathematica. All the file names are numbered as follows datafile.20.0000.out, datafile.20.1000.out, datafile.20.2000.out and so on. I used the ...
4
votes
2answers
156 views

unevenly spaced data

Suppose I have a (very large) noisy data set of points $(x_i, y_i)$ and I want to smooth it. Mathematica seems to have a number of smoothing schemes (...
1
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0answers
93 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 : ...
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2answers
88 views

Select pairs of columns from an array of data [closed]

I try to interpolate the first two columns of a seven-column file formatted as follows: ...
5
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0answers
71 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 ...
0
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0answers
94 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 ...
9
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3answers
203 views

Improving selection of elements from large multidimensional array

Frequently in my profession I deal with large arrays of data. Typically these are mixed types including integers, strings, dates, and reals. To recreate a typical data array: ...
0
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0answers
48 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 ...
0
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1answer
35 views

Right data format when EmpiricalDistribution expects “Rectangular Array”

I have the following code to generate random data (these are the eigenvalues of a non-central Wishart matrix, and I am interested in their distribution). ...
5
votes
2answers
187 views

Exporting row vector as a column in excel

I want to export a vector in Mathematica to appear as a column in Excel. I am trying A={1, 2, 3}; Export["mfile.xls", {"A" -> A}] But it is showing 1,2,3 in ...
2
votes
1answer
113 views

Import selective elements from mixed (text and numbers) data file

How can I import only the 2nd and 5th elements (numbers, located in the 2nd and 5th columns) from all n raws of a data file (.xlxx) that contains both numbers and text. Imported data be inserted into ...
1
vote
1answer
73 views

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

I have a data file, data.txt, having following data: ...
0
votes
1answer
43 views

Automatically restoring the state of a prior session [duplicate]

I have the following problem (I guess a very naive one): I work with some data and make a statistical analysis in Mathematica. I do it over several days and each time I open the file, I have to go ...
3
votes
1answer
91 views

Calculating groupwise mean in Mathematica

I have a huge panel data with more than 2.5 million observations and more than 15000 groups. I want to calculate group-wise mean and I also need Id variable in my result. This is what I have done. ...
4
votes
1answer
128 views

Importing FITS file from HEALPix

I am trying to read FITS file created by HEALPix software. The file contains a spherical map of a scalar field. There is the online support on how to use the file in IDL, but not for Mathematica. I ...
5
votes
3answers
216 views

Creating Correlation Table (and Working) With Missing Data

I am working with data that contains missing values (I have several variables (across the columns) and several observations (across the rows) in an excel spreadsheet). Example of the data structure: ...