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Questions tagged [data]

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

3
votes
2answers
76 views

How to leave only the following strings?

Consider a data having the form data = {{1,7,4,6},{1,6,4,8},{2,4,9,2},{E,...},{1,4,6,3},{4,4,6,2},{E,...},...} i.e., some number $n_{1}$ of rows followed by row $...
1
vote
1answer
29 views

How to remove the given columns and strings?

Consider a data having the form data={{P,4,3,2},{V,7,8,9,55},{P,19,3,4},{V,48,6,1,55}} How to remove all rows with V and then to remove the first column, i.e., ...
0
votes
1answer
37 views

Call a function on a list

I have a list that looks like ...
0
votes
1answer
52 views

PDF for one-dimensional data [on hold]

Consider a dataset data={{x1},{x2},{x3},...}. How to generate a distribution function over $x$ using it? I tried to construct something like PDF[data,x], however ...
0
votes
0answers
35 views

Creating a prediction/distribution based on several years of data

So I have several years of data from a survey. For each year I've used FindDistribution and Predict to see if I can fit the data. Here's one example Where I used FindDistribution to get ...
1
vote
1answer
44 views

Errors in Gaussian fitting curve

I fitted simulation data with Gaussian fitting curve, ...
0
votes
0answers
33 views

Moving average of events per minute

Suppose I have a list of times corresponding to event onset over the course of about an hour (in my case, skin conductance responses from electrodermal activity measurements). The amplitude of the ...
5
votes
4answers
91 views

Import every 50th record from a data file [closed]

I want to import a really big data file which seems like it is too big for Mathematica. That's why I want to import the data in parts. For example, if I have 15,000 rows of data then I would read in ...
2
votes
1answer
87 views

Importing and visualizing 4D data

I am very, very new to Mathematica (I downloaded it 1 hour ago). I have a set of 1000 rows, 4 columns data, in a CSV file: data My first problem is that I don't know how to select the columns in the ...
6
votes
1answer
451 views

Solar radiation data

Is there somewhere in Mathematica I can find direct and diffuse solar radiation for a specific position on Earth ? If not, is there a way to import those data from a website within a Mathematica code ?...
1
vote
1answer
44 views

How to produce ListPlot that samples a given distribution?

I wanted to get a binned plot that a uniform background distribution with a spike at some bin. My first instinct was to use RandomVariate, and then ListPlot. What i get is this This makes sense as ...
4
votes
3answers
139 views

Map list to bin numbers

Does WL have the equivalent of Matlab's discretize or NumPy's digitize? I.e., a function that takes a length-N list and a list of bin edges and returns a length-N list of bin numbers, mapping each ...
5
votes
0answers
52 views

Hyperspectral files in the ENVI format?

Have any of you had the pleasure of reading geospatial / hyperspectral files in the ENVI format? Headers that describe the data here, https://www.harrisgeospatial.com/docs/enviheaderfiles.html which ...
-1
votes
1answer
73 views

Liquefying of Nitrogen & Oxygen Gaseous to Liquid Phase. Thermodynamics. How to plot solution? Solved [closed]

Process of Liquefying of air composed of 79% Nitrogen & 21% Oxygen from Gaseous to Liquid Phases as Follows: 1) When Temperature is higher than T>83 k they both are gas. 2) at T=83 k and less ...
1
vote
2answers
52 views

Reading CSV data from a stream [duplicate]

I'm trying to figure out how many rows/records my csv file has, which I have to stream because it's quite large. Can someone tell me if my approach works and how I can get it to loop through the ...
0
votes
0answers
38 views

Variable Plotted in 3d Space

I am trying to plot dose rate in 3d space in terms of r, theta and z. None of the variables are functions of each other they are just arrays of points with the following sizes: Dose 220x35 r 220x35 z ...
1
vote
1answer
47 views

How to select the data in a given way?

Consider the data data = {{x1,y1,z1},{x2,y2,z2},{x3,y3,z3},{x4,y4,z4},{x5,y5,z5},{x6,y6,z6},...} with N rows. It can be divided into N/6 sets of 6 rows. I want ...
2
votes
1answer
30 views

How to plot one set of data as solid line for one domain and as dashed line for another domain?

Consider a set of data {{x,y}}. How to plot it in the way such that for all x > x0 the plot line will be solid, while for x < x0 it will be dashed?
3
votes
1answer
59 views

What's the best way to import such dataset?

https://www.ocr.org.uk/Images/400305-large-data-set-lds_1-h630-2018-h640-2018-2019-pre-release-data-mei.xlsx What's the best way to import such dataset? I have tried to use ...
0
votes
0answers
31 views

Adding points to plot created with interpolate [duplicate]

I have created plot of my model function: energy[kx_,ky_]:=Sqrt[1-(Cos[kx/2]Cos[ky/2])^2] using the material from question that I have previously asked (Energy ...
3
votes
0answers
65 views

Good habits for handling intense computations with mathematica

I always used mathematica for more "theoretical" computations: maybe I had to handle intricated manipulations, but things that you could almost do on paper. Now I just joined a new project where we ...
1
vote
0answers
34 views

How to visualize and interactively correct time series data [closed]

I am looking for an efficient method to visualize measured time series data with about 100.000 data points per year, such that eye-catching data points may interactively be tagged as suspicious, e.g. ...
1
vote
1answer
43 views

Make a plot from data [closed]

I have two variables $x$ and $y$ satisfying, say, $y^2 + x < 1$, such that $0 \le x < 1$ and $0\le y<1$. I want to plot all the points satisfying the inequality $y^2 + x < 1$ and also show ...
0
votes
1answer
32 views

How to close the contourplot3D from top?

I received a very nice solution by Chip Hurst to make my 3DContourPlots smooth and closed in here. Now I have another problem that is simpler but I still want to know the ideas of the others. The data ...
1
vote
1answer
59 views

How to make the ListContourPlot3D smooth and closed?

I am struggling with making my plot in ListContourPlot3D smooth and closed. I have seen so many posts regarding the same issue but in other functions, the solution of which can not be applied to ...
2
votes
2answers
54 views

Median of multiple lists of points

I have three lists of points that I want to combine, take the median of and then plot. I'm not entirely certain how to combine and median them. They are data points from three different months, and ...
0
votes
0answers
43 views

Ignoring text when converting strings of text to numbers

I have a string of measurements--mostly numbers, but occasionally an NA. Right now Mathematica is reading it all as text, so I'm using ...
1
vote
1answer
41 views

Building a data frame from a list of lists of lists

OK, let's say we have a following list of lists of lists: ...
2
votes
1answer
67 views

Label quartile / quantile data

I searched for a WL implementation of the Python Pandas qcut function but could not find one. Anyone aware of an implementation? For the moment I just need quartiles and the assignment of values in ...
-1
votes
1answer
137 views

Importing large csv files [duplicate]

I'm trying to import a large csv file (around 1.5GB) so I can multiply one of the columns, and plot it against another. There are seven columns in the file when I try and open it in excel, and I need ...
0
votes
1answer
54 views

Plotting massive amount of data

I have to plot a huge amount of data. I have only one file, I've already imported it. The file contains the following: 48 separate smaller fractions. Every fraction begins with six numbers (which ...
1
vote
2answers
35 views

How can I get LanguagesFractions data in different years?

I want to do that. But it failed. May I change my code? Or Where can I get these data?
0
votes
1answer
48 views

Where can I get these data?

Look at this, I want to find such data, but I found Wolfram doesn't have. May I use other code?
0
votes
3answers
123 views

Find peaks in data set and correlate variables [closed]

I have a data set composed of a X variable (col 1) and two Y variables. Y1 shows roughly 40 peaks while Y2 is a linear function. Is it possible to find the approximated 40 Y2 values for which Y1 is a ...
0
votes
1answer
67 views

Fitting data using a parametric differential equation

I was fit the data using differential equation(eqns) and pfun I tried data fitting (I gave the parameter directly..a=22500, b=10^-22, c=2*10^-40 and scaling factor k=1.04 10^-36) ...
1
vote
1answer
44 views

Rule based list manipulation

I'm trying to restructure the following expression: start = Table[{1, 2, 3, 4}, 5]; Join[{ToString /@ {first, second, third, fourth}},start] Into this: ...
1
vote
0answers
50 views

K-medians clustering computation

Is there a built-in function for data clustering using k-medians algorithm? I found out about the ClusterDissimilarityFunction of the ...
0
votes
1answer
97 views

numerical solution of nonlinear differential equation : parameter fitting

I want to fit data X-axis and Y-axis are L and P, respectively n'[L,t] == L a - b n[L,t]^2 - c n[t]^3, n[L,0]==0 a,b,c is independent parameters. P value is ...
3
votes
1answer
159 views

Cleaning away data points which are enveloped within a function

I have some data taken in an experiment which I want to fit and analyse. But before I start fitting function, I want to clean points away in a robust but elegant way. I first provide some sample data ...
0
votes
1answer
37 views

Fit data with a given function depending on parameters

I want to fit the data of a star's temperature with a function from a model. That function depend on several parameters. I want to know how can I find the value of those parameters. The data is: <...
0
votes
1answer
80 views

Density plot with a list of $ (x, y) $ data

I have a list of $ (x, y) $, say {{x1, y1}, {x2, y2}, ..., {x1000, y1000}} and would like to make a density plot. I understand that I may categorize the data into ...
0
votes
1answer
38 views

How do I extract data points from an audio plot at a constant spaced time interval?

AudioPlot[Audio[File["Downloads/1_mp3.wav"]]] data = Cases[AudioPlot[Audio[File["Downloads/1_mp3.wav"]]], Line[x_] :> x, Infinity] This code can extract data ...
4
votes
0answers
54 views

Candidate sampling for softmax neural networks in mathematica

Though I've been using mathematica for a few years, I've never really delved into its ML capabilities (except for the occasional clustering). I'm curious if anyone who has some experience using ...
2
votes
3answers
85 views

Merge Associations and replace absent value with 0

I have two associations like this ...
3
votes
3answers
146 views

Rank Transformation of an Array

Is there a built in function which rank transforms an array of data? By rank transformation I mean data = {2.4,5,1,6,7,10,2} Rank[data]={3,4,1,5,6,7,2} where ...
1
vote
2answers
106 views

Sampling data from numerical values of density distribution of nucleons

How could i sample my data which follows distribution if i have only numerical values of density distribution as an example data attached as in picture I tried but do not know how to do it. The data:...
2
votes
4answers
140 views

Subdivision of a line into n intervals of linearly changing length

This question is separate, but connected to my previous question on this site, that can be found here. Let's say that we have a line of length X (in this case X=5), defined by a list ...
4
votes
4answers
158 views

Linearly change the step size in a table

I am trying to create a table of points, where the size of the step would change linearly from a certain value to another. Bellow is a simple code to demonstrate a table of points with a constant step ...
-1
votes
1answer
92 views

Functional operations with data [closed]

I have the following data (a shorter sample of the whole data) : ...
2
votes
1answer
390 views

Converting built-in Mathematica symbol to C [closed]

I am trying to convert my Mathematica code to C since it can sometimes takes the Mathematica code quite a while to execute since the arrival times lists are hundreds of thousands of counts long, and ...