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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14
votes
2answers
309 views

upper envelope of data

Here is a ListPlot[] of some data. Clearly, there is a fairly smooth upper envelope - the question is whether there is an nice way of extracting it...
5
votes
1answer
97 views

FInding outliers in multiple dimensions

I'm working on dataset which isn't normally distributed.which contains three dimensions like cost, discount and profit I'm trying to find outliers in all these dimensions. I used z score to find ...
6
votes
1answer
46 views

KaryTree of Text .csv and Correlation

How can I make a KaryTree of this raw-data (raw-data at the end of the question): This is is data from a political survey in which I ask 5 questions with the following possible answers: Q1: 'Y'= ...
-1
votes
1answer
47 views

How to run code and do data analysis in mathematica [closed]

I am a beginner in Mathematica. I'd like to do something like the following: write code- ouput- write code- output... But when I created my own notebook and copy the code above, I don't know how to ...
2
votes
2answers
114 views

Best way to include a “singularity” in a SmoothHistogram?

I have a dataset like this: data = {0,0,1.1,1.3,0,0,3.4,0,0,2.3,0,0 .....} You can imagine that data is generated from a ...
2
votes
0answers
74 views

How can I access the Criterion function of KI method in `FindThreshold` for a dataset?

I want to find a threshold for some data set, using Kittler-Illingworth minimum error thresholding method (KI method). To do so, I use the Mathematica built-in function ...
18
votes
0answers
331 views

How does Dataset compare to DataFrame in pandas?

Pandas is a Python package providing fast, flexible, and expressive data structures designed to make working with “relational” or “labeled” data. Just like ...
3
votes
1answer
94 views

Speed up computation of sum from large matrix

I have a 3x3 matrix (252^3) of data (densities) and I want to compute a correlation xi from nearest neighbours as well as a sum involving a check whether the density is in a certain bin. The ...
3
votes
2answers
127 views

Finding mean of data sets with unequal length

I have two data sets on the form (x,y) of unequal length: ...
1
vote
1answer
58 views

Extract data from contour [duplicate]

I have a ListContourPlot, and I'm interested in extracting the data of one of the contours. Here is an example and I highlighted the contour that I would like to extract the data from: ...
1
vote
0answers
35 views

Fitting Data when both Variables Have Uncertainties [duplicate]

Does there exist a method in Mathematica for fitting some function f(x; a, b)=y (with parameters a, b) to data of the form {x, y} when both x and y have different uncertainties? It seems like it would ...
4
votes
2answers
56 views

Excluding Specific Rows Using Import[…]

As the question states, I'm trying to import a .csv file but I would like to exclude certain rows (points which I know are bad data). This is easy when the points ...
2
votes
0answers
45 views

Optimization for iterating and plotting a matrix product and its elements?

I have an iterative matrix product of this type Since i didnt knew how to do it, I explicitly wrote the product as {Ayn + Bxn, Cyn + Dxn} and evaluated it with the NestList construct ...
2
votes
0answers
38 views

How to use a picture to store some data [duplicate]

As we know.The values of the types is "Real" defaultly in Mathematica.In the Image documentation's detail we can see ...
2
votes
1answer
82 views

Fitting EV charging curve

I would like to fit my set of data (x = time and y = power) as seen below, and obtain function of x describing it as close as possible, in order to manipulate it (applying different SOC, time offsets ...
0
votes
2answers
53 views

Plotting plane from a matrix or data table

After weeks collecting data I've decided to pass my results through Wolfram Alpha and see what it gets. The results are amazingly useful, specially the plane generated by linear regression. It is ...
2
votes
1answer
72 views

Help with Time-Seried dataset

I can't seem to figure out the best way for directly inputting interpolated values into a dataset. I turn to your expertise for guidance. So, I have a multi-year time-series dataset. Column 1 is time ...
0
votes
1answer
56 views

Make Function from matrix [closed]

I have a set of excel data (time v temperature). When I extract it to mathematica it creates a matrix. I want to put the temperatures into a function that is time dependent, so is there a way to use ...
-1
votes
2answers
62 views

Matching timestamped data

I bet this question is a gimme for most of you guys, but I'm having a bit o' trouble figuring it out. Thanks ahead of time for your input and help. Soooo, I have two datasets where column 1 is a ...
3
votes
1answer
91 views

Getting correct amplitudes with Periodogram

I'm having some trouble with the function Periodogram, mainly with getting it to produce correct amplitudes for the spectrum it returns. My question is how to fix ...
1
vote
0answers
56 views

Constructing the spectral density of white noise

My goal is to find the spectral density $S_{XX}(f)$ from a time domain noise signal $X(t)$. The approach should work for general time series, but to illustrate what I've been doing I'll keep it ...
0
votes
2answers
46 views

Euclidian distance matrix from a set of points [duplicate]

I have a set of points and I like to compute the (pairwise) euclidian distance for those points. The set has a form like this: ...
1
vote
1answer
109 views

Extracting Features from a List

Data: https://drive.google.com/file/d/0B7G3oUuZG1TwYWhMVUhSQzNwTEk/view?usp=sharing Here I have 20 datasets collected from custom built EMG sensors monitoring a users face. I am particularly just ...
1
vote
0answers
44 views

Save experimental data within notebook. Is it possible? [duplicate]

I'm trying to use Mathematica for all my scientific needs as much as I can, so I can learn. When I want to plot my experimental data using Mathematica, I've been Import[] and plot data sets. However, ...
0
votes
1answer
55 views

Most elegant way to plot from you data file (xy, xy, xy… format)

I have a simple question and it could be very basic tips for many. I tried to find the answer several hours by searching, but couldn't find the way yet. My question is, if I have a data set (x1y1, ...
0
votes
0answers
21 views
1
vote
1answer
65 views

How to visualize .data files? [closed]

I am working with simulation models trying to carrying out some predictions in ocean waves and this stuff. (MITgcm) I am able to run the program and generate hundreds of .data and .meta files, but i ...
1
vote
2answers
154 views
0
votes
1answer
73 views

Applying a formula to the data in several files [duplicate]

I am calculating with the depth data recorded in a number of files with extension .log. The depth data is like this and I loaded it by means of Mathematica: ...
3
votes
1answer
89 views

Do Any of the filter functions perform a LOESS or LOWESS filter?

From the Data Transforms and Smoothing guide there is a link to the Linear and Nonlinear Filters guide. Do any of these filter functions perform a LOESS or LOWESS filter on set of paired data? ...
9
votes
1answer
168 views

How to do Independent Component Analysis?

The new experimental function in 10.3.1 DimensionReduce[], has the following three options for Method: ...
0
votes
1answer
68 views

Interpolate the discrete list into continuous function

I have a data whose list plot shows up following graph I would like to interpolate the missing data and make the function continuous but for particular x-coordinate there is multiple values of $y$ ...
16
votes
3answers
767 views

Export dataset to JSON including Unicode Characters

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

Spacing control in export

While using, for example, the code ...
20
votes
3answers
571 views

Detecting components in timeseries

I'm looking at this sequence of values: I'd like to detect the points where the center of the time-series shifts (around x=1000 and x=2000). Many of the transforms and smoothing methods I have ...
3
votes
0answers
85 views

WDF specification?

Motivated by a recent question on the meaning of all sorts of W* acronyms, I would like to get more information about the Wolfram Data Framework (WDF). On its web page ...
1
vote
1answer
45 views

How to export data from ListLogLogPlot [closed]

I have a ListLogLogPlot, for example: data1 = ListLogLogPlot[Table[{i^2, i^(1/3)}, {i, 1, 20, 1}]] Note: I know that there is ...
6
votes
4answers
260 views

Average dataset with many repetitions?

I have a dataset where each item is of the form: <|"p1" -> x1, "p2" -> x2, "r1" -> y1, "r2" -> y2|> The interpretation is this: ...
2
votes
1answer
65 views

Fitting data in Log-Log scale

I want to fit my data from a txt file to a curve in log-log scale. What I tried to do was this: ...
2
votes
1answer
47 views

Convert table data to Classifier data

I want to convert excel data into Classifier acceptable data. For Eg, the inbuilt Titanic data for Classifier is structured as below: {"1st", 29., "female"} -> "survived" I have 4 columns in ...
4
votes
0answers
92 views

Fitting data with unique variable per measurement

Imagine we are in the following situation, we have a nonlinear system of functions $f$ with coördinates $x_i$, and unknown parameters $\delta_i$'s and $t$. Let this system be defined as, ...
5
votes
3answers
289 views

Histogram of a very large dataset?

I have a very large dataset stored in a file (over 2GB). The file contains a tab-separated table of floating-point numbers. I want to do an Histogram of all the numbers in the table. But if I try to ...
1
vote
1answer
82 views
3
votes
1answer
109 views

How to plot data with domain on a circle?

I've got a list of data of the form {{0,x0},...,{359,x359}}, which represents some experimental results given in polar coordinates with fixed radius. How to plot ...
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 ...
0
votes
1answer
86 views

Manipulate a graph from data

I want to manipulate some data, to do this i create a graph. But i don´t know how to manipulate the data. ...
3
votes
1answer
112 views

Why is TimeSeriesForecast linear?

When I use FinancialData with TimeSeriesForecast, the resulting graph is always linear and thus not very accurate. ...
6
votes
2answers
590 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 ...
0
votes
1answer
82 views

FindFit and log norm function

I'm trying to fit a function to data using FindFit, but I can't find a way to replace norm function RMSE with a RMSE in log space: ...
1
vote
0answers
63 views

Convert large KML coordinate datasets to UTM [closed]

I was wondering if there are ways to convert massive amounts of KML coordinates into UTM coordinates using Mathematica. Other programs would also be acceptable. Thanks. I have the KML file from ...