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0
votes
1answer
51 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
votes
3answers
151 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
68 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
votes
1answer
146 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
104 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
votes
0answers
38 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 ...
1
vote
3answers
141 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
43 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
46 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
62 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 ...
4
votes
2answers
123 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 ...
1
vote
2answers
64 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
51 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
89 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
142 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
vote
0answers
86 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 : ...
0
votes
2answers
75 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
votes
0answers
66 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
votes
0answers
60 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
votes
3answers
193 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
votes
0answers
45 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
votes
1answer
27 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
124 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
56 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
60 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
40 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
90 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
106 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
165 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: ...
5
votes
1answer
121 views

Tools for Importing/working with SEED seismographic data in Mathematica?

Do you know if exist a library or a package in order to import and work with SEED Seismographic data in Mathematica?
11
votes
2answers
314 views

Map of United States as a 3D histogram

By combining the state data from here and the extrusion code from here I have managed to make prisms of the various US states such as However, the extrusion method looses information about the ...
1
vote
1answer
89 views

How to get matching starting dates for different `FinancialData` properties? [closed]

Why do the "Return" and "Volume" outputs of FinancialData differ? Consider the following ...
0
votes
0answers
99 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 ...
14
votes
1answer
239 views

Export dataset to JSON

I'm experiencing a weird issue. Consider a dataset defined like this: dataset = Dataset[{<|"a" -> 1, "b" -> 2|>, <|"a" -> 3, "b" -> 4|>}]; ...
7
votes
0answers
134 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: ...
2
votes
1answer
104 views

Extract data from WeatherData as a list of associations

Given weather data for 2013 and 2014 as follows: ...
14
votes
4answers
1k views

How to change element color in Periodic Table?

The command ColorData["Atoms", "Panel"] generates a periodic table. As I don't want to reinvent the wheel, I asked myself how to change the color of each cell ...
6
votes
1answer
79 views

How to provide data to users in a way similar to Mathematica's curated data

How can one go about implementing a custom data backend usable by Mathematica? For example something like CountryData or ...
1
vote
0answers
28 views

Updating values in a Dataset [duplicate]

I'm starting to work with datasets. They seem like a useful addition to Mathematica. However, there's one fairly major stumbling block I can't get over. How do I update data in a dataset? I have a ...
4
votes
1answer
224 views

How to clean up messy data

The start of my question is about one specific situation - I have some erroneous lat/long values in a dataset which I need to clean up. But I'd like it to cover the overall topic of cleaning up messy ...
6
votes
3answers
226 views

A Case of DeleteCases for WeatherData

I am trying to use ListVectorPlot in combination with WeatherData and CountryData to show ...
1
vote
1answer
101 views

Setting a Row from a Matrix as Variable

I'm not advanced in Mathematica but I'm trying to get better. I have a big set of Data and I want to Plot the first row against ...
1
vote
1answer
124 views

Convolving data set with gaussian profile

I have a spectrum looking like List, and I want to convole it with a gaussian of the form PDF[NormalDistribution[μ, σ], x] (where σ also depends on x). The raw ...
4
votes
1answer
180 views

How to create a real-time dashboard in Mathematica?

I am trying to figure out how to use Mathematica as a real-time interface. I've used Excel/ODBC connection to a SQL database to use the graphing functions within to get my real-time dashboard. I ...
1
vote
1answer
126 views

Distance between data and curve

I have two datasets: ...
2
votes
2answers
85 views

Obtain data points from a density plot

I have a density plot, for example DensityPlot[Sin[x*y],{x,0,2pi},{y,0,2pi}]. Then I would like to collect points from this densityplot into a file so that I ...
3
votes
1answer
157 views

BarChart that lines up with dates in DateListPlot

I am trying to create a chart similar to the view offered by TradingChart, but with custom data not relating to finance. ...
0
votes
1answer
87 views

Problem of how to manipulate Taylor/McLaurin series

I'm new to Mathematica so I don't know very well the program itself. I would like to manipulate as he does this person in youtube: http://www.youtube.com/watch?v=fCJHvQaGNiQ But I put all the ...
1
vote
0answers
76 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
52 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 ...