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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2answers
61 views

Use cases to exclude data values over a certain threshold

I am trying to parse data output from a fluorometer. My output is basically signal intensity over time. So I have a list of 2 value lists with the first value time and the second signal e.g., ...
0
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0answers
53 views

Why is the Output of Mean and StandardDeviation an expression, and not a value? [closed]

I'm using Mathematica for the first time, and to practice, I want to manipulate a matrix of data. My problem is that when I use the Mean function on the matrix, or the StandardDeviation function, I ...
1
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1answer
51 views

Local Max/Min from the list with fluctuation

I am trying to find the local minimum of the list of data with some noise. Here is how the data looks like below image, and I want to extract the three points. From an question by giacomo (link), I ...
1
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1answer
61 views

How to convert a Number to String for Export a Table

I am generating a table with 4 columns, wheras only the columns 3 and 4 have the same length. ...
2
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0answers
29 views

How do I import an entire column from an Excel Sheet [duplicate]

The Wolfram Documentation gives information on how to import an entire sheet, and an entire row, but not an entire column. Currently, the code I have been trying to contort into a working form is: <...
1
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1answer
50 views

Sorting Data by Differences between Columns

In Band Structure calculations one gets rather extensive data of Energy Values (Eigenvalues) and the associated Eigenvectors out of the solution of an Eigenequation of e.g. the form H.$\psi$=E.$\psi$. ...
29
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4answers
1k views

Filtering beat-to-beat heart rate data

From an experiment, I have a dataset of beat-to-beat heart rate data: a list of the time between each heart beat in [ms]. The data is measured using an infrared optic sensor at the finger tip. The ...
1
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1answer
68 views

Nested parameter selecting in Manipulate

I have the following code, stripped down from the original to the bare essentials: ...
3
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2answers
67 views

Picking a dimension from an interpolating function

I have an interpolation function. Lets think of it as f={fx,fy,fz}. I would like to operate on the fx part of interpolation and say, multiply it by five and plot ...
3
votes
1answer
70 views

Dealing with a large number of optimizations performed with parameters read in from a CSV file

I have a large CSV file (1.5M rows), with each row containing a set of parameters that I need for an optimization routine in Mathematica. I'm hoping to import the data, run the computation, and then ...
4
votes
1answer
114 views

How to apply BinCounts to weighted data

For example, I have an array: data = {1, 2, 3, 4, 5, 6, 7, 8, 9} and a corresponding list of weighting factors ...
1
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2answers
68 views

Reading simple data csv file containing “e” and “i”

I can't find a way to properly read a csv file containing complex numbers in the following form: ...
0
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2answers
61 views

Fitting log-linear data

I am using NonlinearModelFit to extract the gradient of what appears to be linear data in a logplot: ...
0
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0answers
29 views

data fit using second order PDE

I'm trying to find the parameter for second order PDE using data. i don't know what is the error of that, ...
1
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1answer
46 views

Using distribution of data instead of data in `EstimatedDistribution`

Because of huge amount of data, the data saved in their frequency. for example {1,1,1,1,1,1,2,2,1,2,2,1,1,2,1,2,1,3,24} saved as ...
1
vote
3answers
100 views

Importing data from notepad to mathematica

I have a set of numbers in notepad that I want to import into Mathematica as a list. I could do this manually, but it will take forever, and my hands are getting tired. My issue is that I'm trying to ...
1
vote
1answer
99 views

How to read a part of huge matrix saved in a TXT file as single expression?

I saved a huge matrix of numbers with dimensions {400, 4001, 2} using Put and got a TXT file formatted in the following way: <...
1
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1answer
36 views

Plotting x value and error bar in y from a data file

Here are some of the points where first column is the values on x axis and the other two values are lower and upper limits for the error bars in y. ...
1
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2answers
57 views

DiscretePlot: differentiate without using different colors

I need to plot multiple series in the same figure. As the picture will be printed in white and black only, how can I differentiate these series so that readers can identify them from each other? ...
0
votes
1answer
72 views

Extracting the data of each frame from an AVI file

What's the most straightforward way to "Import" the data of an AVI video? For instance, if I record a 30 frame per second video, then after 10 seconds I would have 300 frames. How can I import the ...
13
votes
2answers
290 views

How to do Independent Component Analysis?

The new experimental function in 10.3.1 DimensionReduce[], has the following three options for Method: ...
17
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4answers
404 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...
2
votes
1answer
77 views

Apply function to a part of a list [closed]

Let's say I have some data: data={{a1,b1},{a2,b2},{a3,b3},{a4,b4},...} and I would like to apply the function: f1[x_]=x*5 to ...
2
votes
2answers
139 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 ...
3
votes
0answers
63 views

What's the most efficient way to load a very large dispatch table?

This question is possibly related to this topic, although I think I have something a little more specific in mind. Recently I've been working with dispatch tables for a project, since it seemed like a ...
5
votes
1answer
103 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 ...
7
votes
1answer
51 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
65 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
0answers
78 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
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0answers
379 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
103 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
143 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
68 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
72 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
46 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
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0answers
46 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 Image[...
2
votes
1answer
88 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
62 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
84 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
59 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
65 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
111 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
70 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 simple:...
0
votes
2answers
53 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
124 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
59 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
23 views
1
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1answer
76 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 ...