Questions on systematic data handling and analysis, including data correction, manipulation, or selection of user-data or built-in data available with Mathematica.

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1
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1answer
98 views

How to create a column for ordering values

I have a dataset, where some data has to be ranked in regard to the number of ranking of the total dataset. I've made a simple example below: ...
1
vote
2answers
315 views

From a list of (x,y) pairs, generate a new list of (x,ymean) pairs, where ymean is the average of all y's with the same x in the original list [duplicate]

This seems like the sort of thing where Mathematica can give a very simple solution. I have a list of points {x,y}: ...
0
votes
1answer
234 views

Importing a text file into a matrix format

I am attempting to perform a comparison of pseudorandom number generation with the RAND Corporation's "A Million Random Digits with 100,000 Normal Deviates" for a Computational Physics course. I have ...
4
votes
2answers
956 views

What is the Mathematica way of joining two tables?

Is there a special Mathematica way of joining tables of data together, so that I would get similar functionality as if I was running a database with sql? For example, I have one particular table ...
0
votes
1answer
40 views

save all inputs as list [duplicate]

I received three results of calculations: {k->0.190729} {k->0.197575} {k->0.249319} Could you help me write the results in the following form: ...
15
votes
3answers
1k views

Parametric Interpolation of 2D data

I want to create an interpolation through the following 2dim data points: ...
2
votes
2answers
658 views

List density plot for non-uniform data

I am trying to make a density plot to show the data that can found here. I tried with GNUplot previously. The result of GNUplot density plot for a rectangular set of data. I am able to do this only ...
5
votes
4answers
560 views

Breaking a sorted list into bins of a specified size

Can somebody please explain me the following: If I try to split data every increase in 0.5: ...
2
votes
1answer
781 views

Data filtering using Butterworth filter

I want to filter data using Butterworth filter. I am currently using Matlab and I want to know how to do it in Mathematica. I have the following data: ...
2
votes
1answer
404 views

Importing data from excel and assigning a variable to each of its columns

How should I assign variables to the data imported from excel containing 3 columns which are time, mean and standard deviation. I want to perform operations on the three variables to get new ...
1
vote
1answer
204 views

How to efficiently distinguish the rewired edges in WattsStrogatzGraphDistribution?

The WattsStrogatzGraphDistribution function is a way to construct random graphs based on Watts and Strogatz small world model. The ...
12
votes
3answers
2k views

Smoothing ListContourPlot contours

I have some data of type {{x1, y1, f1}, {x2, y2, f2}, ...} and want to do ListContourPlot. However, there is a problem that the ...
0
votes
1answer
345 views

How to prepare (copy/paste) data from Matlab?

What is the best way to get data from Matlab to Mathematica? For a new project I want to copy/paste a table (or part of it) of datas from Matlab to Mathematica. Copyed from Matlab it is: ...
0
votes
1answer
223 views

Bar Chart: How to adjust the font size for the bar labels as the chart size is manipulated

I have data that represents the binding energy of oxygen on different surfaces. Each bar is a different transition metal, and the length of the bar is the binding energy of oxygen. How do I make the ...
1
vote
1answer
235 views

show fit information on plot

After performing a fit in Mathematica, I would like to show the fitted parameters in a box on the plot showing the fitted function. How would I go about achieving that? Here is a MWE: ...
6
votes
3answers
963 views

Calculate mean of values in bins

Problem description: I have a list of $\{x,y\}$ pairs. I'd like to divide $x$ into equal[*] bins, say $bx_1, bx_2, \ldots$, calculate $\left<y\right>$ for every bin and then plot the bin values ...
19
votes
3answers
1k views

How to extract the edge from a set of points

I have an accumulation of points representing a body as you can see in the image below. From this data I want to generate a list of points or a curve, which is the envelope. The first idea was a ...
2
votes
1answer
125 views

nonlinearnodelfit with a matrix as weights

I have to fit a non linear model to my data and I am trying to use nonlinearmodelfit. The problem is that I have systematic errors, so the ...
6
votes
2answers
587 views

Map of Swedish regions?

There have been some questions dealing with how to draw individual US states since such data doesn't come with Mathematica through its CountryData which offers ...
1
vote
1answer
88 views

Forcing contours to close at edge

I have some data that I am plotting with ListContourPlot and I would like my contours to be closed at the edge (closing around the high value region). A simple ...
3
votes
2answers
733 views

Removing trailing zeros from a list

If I have a list like list1={2334.,342.,0.,0.,2322.,0.,0.,0.,0.,,,,,,}; it's easy to remove to trailing blanks with ...
4
votes
4answers
603 views

More elegant way

I read ReplaceOrRemoveInvalidOrMissingData Mathematica documentation, and I tried to apply the same approach to my dataset. I've got two problems, but one is only a style problem! There is one more ...
8
votes
2answers
762 views

Correct fourier scaling and high-resolution frequency identification

I have a dataset of amplitude versus time $(t,A(t))$ and I need to extract the dominant frequency and amplitude, and also get the amplitude at one other specific frequency. My data looks like this: ...
4
votes
1answer
892 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: ...
0
votes
2answers
57 views

Filter through list and lump data [duplicate]

I have a very large data set (around 3000) that looks like: ...
1
vote
1answer
191 views

Exporting a list as RawData or Data

My problem is quite simple yet I do not seem to figure out the solution to it. I am simply trying to export a list in Mathematica, actually a list of lists of lists etc, something like ...
2
votes
2answers
192 views

Plotting data in a weird format

I have a lot of data on the following form: data = {{param1,param2,param3,param4,{{x1,y1},{x2,y2},...,{xn,yn}}},...} The first variables in each sublist are ...
1
vote
1answer
297 views

How to export data in scientific form

I am having an issue about how to export data in its scientific form using Mathematica. To be concrete, I define a list ...
2
votes
1answer
141 views

Represent more nested dataset with the same color in the PieChart

I have multiple dataset that I want to plot in PieChart, as in PieChart[{{2, 2}, {1, 2, 4}}, ChartLayout -> "Stacked"] Now here is the catch: I want the color ...
2
votes
0answers
827 views

histogram fit for probability density [closed]

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 ...
3
votes
2answers
282 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: ...
3
votes
3answers
569 views

For-loop not working as I expect

I want to do this: When 10 <= t < 130, give t -> 1; When 130 <= t<300, give ...
1
vote
1answer
151 views

Find Numerical Derivatives (With Errors) given some data

I have a question. Suposse I have some data with their respective errors: ...
7
votes
1answer
272 views

Assign the contents of a “Copy” operation programmatically to a variable?

While an earlier question Cut and paste data from a spreadsheet nominally addresses the issue, a year has past since its OP asked it and I hope that others have come across simpler or more direct ...
3
votes
2answers
260 views

Multi-Fitting with Nonlinear model

I want to fit experimental data by the H-N model. Here is the H-N model: $$\text{EHN}(T)\text{=}\text{E$\infty $}+\frac{\text{E0}-\text{E$\infty $}}{\left(1+\left(i \omega\tau(T_g)10^{-\frac{\text{C1} ...
23
votes
5answers
2k views

Graph databases / Nosql with Mathematica

I am very new to mathematica but it looks like an interesting language and I would like to explore it for a future project to create a web search engine. It seems like it would be fairly well suited ...
19
votes
5answers
2k views

Moving maximum function?

How can I construct a moving maximum function? For example, if I have a list of 12 values: { 5, 6, 9, 3, 2, 6, 7, 8, 1, 1, 4, 7 } and I want to maximize over 3 ...
5
votes
3answers
405 views

Determing two Nonlinear model fits with 95% confidence bands from one data set

I have the following data which is postulated to have contributions from two different sources .....as can be seen from the confidence band, many points are out of the band. Question: How can I ...
4
votes
1answer
251 views

How to get an equivalent of WeightedData in Mathematica 8?

Is there an equivalent command of WeightedData (new in version 9) in Mathematica 8 or I have to define it by myself? I haven't found anything in the site or ...
2
votes
1answer
123 views

WeatherData function problem: “NonMetricValue” returns undated list of values

In the WL example below, WeatherData[] returns an undated list of values when I add the annotation "NonMetricValue." ...
4
votes
1answer
313 views

FindFit not giving a good fit despite good initial parameters

I'm having a problem with FindFit not giving a good fit to my data, even though the initial parameters I give look really good when plotted. The fitting function is ...
2
votes
0answers
67 views

How to save all variables in the workspace into a file? [duplicate]

I did some time consuming computation and obtained a lot of arrays and variables; however after restart the Mathematica Kernel, all these computational results disappeared. How can I save all these ...
12
votes
2answers
4k views

Finding fourier transform of data and hence frequencies

I looked at all the other questions related to mine before posting this, and they didn't solve my problem. I have a large data set which can be downloaded from here. I'm using the following code to ...
6
votes
1answer
818 views

Having trouble fitting data using NonlinearModelFit

I'm trying to fit data = {{2002, 45000}, {2004, 90000}, {2005, 120000}, {2013, 211000}}; to an exponential function ...
12
votes
2answers
1k views

Filtering and Replacing outliers

I have a set of data that measurements of temperature vs time (date). It is easy to realize when the sensor went wrong as one might see a blip on the data. How to teach to Mathematica to: 1) Detect ...
8
votes
1answer
263 views

How to reconstruct a missing data point

In the output of a large computer simulation(thousands of cpus for 3 days), I found that one data point is missing in the result. Is it possible to reconstruct the missing value using the remaining ...
2
votes
5answers
541 views

How do I find the maximum value from the given set of data?

I have a set of data like {{x1, y1},{x2, y2}, ...,{xn, yn}}. From this data can I find the value of x for which ...
2
votes
1answer
268 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 ...
0
votes
1answer
171 views

How to adjust the correct ImageSize between two plots

Let's consider the following simple plot ...
3
votes
1answer
170 views

I need a technique for determining and drawing a line where the density in a listplot jumps up suddenly

Basically I have a two dimensional list plot with a bunch of points between the square of (0,0) and (1,1). The y-values of these points are drawn from a uniform probability distribution between 0 and ...