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2
votes
4answers
491 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 ...
3
votes
1answer
220 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: ...
2
votes
1answer
101 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
45 views

Filter through list and lump data [duplicate]

I have a very large data set (around 3000) that looks like: ...
1
vote
1answer
113 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
181 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 ...
0
votes
1answer
79 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
94 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 ...
0
votes
0answers
168 views

histogram fit for probability density

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 ...
2
votes
2answers
144 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
437 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 ...
6
votes
1answer
143 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
159 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} ...
10
votes
2answers
415 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 ...
13
votes
4answers
1k 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 ...
-2
votes
1answer
107 views

Data is imported as string instead of numbers [closed]

newdata = Import["data.txt", "TSV"]; ListPlot[newdata] My data.txt file consists of two columns of numbers, separated by ...
1
vote
1answer
141 views

Projection of Density Plot [closed]

Say I have a density plot such as DensityPlot[Sin[x]*Sin[y],{x,-2,2},{y,-2,2}] Is there a way to see a projection of this plot. For example is there a way to see ...
0
votes
1answer
50 views

Reap/Sow: strange behavior with tags and functions [closed]

I was trying to use strings as tags for Reap/Sow and I've found out the following strange behavior when I also add a function as the third argument of Reap[]: ...
3
votes
3answers
230 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
112 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
65 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
195 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
56 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 ...
10
votes
2answers
791 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
286 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 ...
3
votes
2answers
287 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 ...
6
votes
1answer
177 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 ...
1
vote
5answers
170 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 ...
1
vote
1answer
117 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
117 views

How to adjust the correct ImageSize between two plots

Let's consider the following simple plot ...
3
votes
1answer
121 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 ...
2
votes
2answers
152 views

Need help in making a fit to my experimental data

This is what I have done so far. The points are of angles-of-deviation and wavelengths from my physics lab experiment. ...
1
vote
1answer
57 views

How to extract data beginning on the closest number to zero?

I have a list from which I want to extract only the values beginning from where b (from {a,b}) is the closest to zero. For example: I want extract data={{2, -0.036704}, {56.7499, 0.95489}, {73.7349, ...
1
vote
1answer
133 views

Need help with extracting columns from a table

I'm trying to clean a dataset of unnecessary variables but I constantly get an error when doing so. Following an example where: ...
6
votes
2answers
165 views

Implement planar correction for skewed 3D profilometric data

I have some data that represents small-scale surface topography. The data is planar but not flat because it's impractical to level this microscope to a tolerance of microns. It looks like this: I'd ...
1
vote
2answers
112 views

How to extract data depending on Position of First zero?

I have a file (attached as an image) which I imported to Mathematica and only extracted the first and second column. My problem is that I want to extract the data beginning from the row where $A=0$. ...
1
vote
0answers
30 views

How can I convert a matrix into matlab form string? [duplicate]

How can I convert a matrix into matlab form? ...
2
votes
2answers
146 views

How to delete all rows in datafile that contain a string

I'm importing some data from a file. However, the file was created by an unreliable instrument, such that the data looks like this: ...
2
votes
1answer
110 views

Read C-formatted hexadecimal numbers?

I have a lot of 32-bit numbers in hexadecimal symbolized as they are in C (for example, 0x1230abde). How can easily read these in Mathematica?
3
votes
2answers
182 views

Import numeric data into Mathematica

I have a C++ program that outputs a set of numbers at each time step. A blank line separates successive time steps. Here is an example of my data format: ...
3
votes
2answers
199 views

Selecting for 2D points that are within a threshold distance of an upper- and lower-bound number of points

I have a very large set of 2D points: numberOf2DPoints = 10^6; pointList = RandomReal[{0, 1000}, {numberOf2DPoints, 2}]; I'd like to find a way to quickly ...
1
vote
1answer
91 views

Reading between blank lines in external data files

I have an external data file with several columns and thousands lines of data. For the sake of this question, let's assume that we use ...
1
vote
2answers
80 views

Missing something in my input for CountryData dependencies

I'm trying to find (a)which countries have dependencies (b)and a list of countries that consider themselves dependencies (c)and a list of countries that don't consider themselves dependencies. ...
0
votes
0answers
48 views

Is there SVM packages available for free? [duplicate]

I want to do date minings. And do you know some packages that have been made available online? I am using Mathematica 8 and 9. Thanks.
0
votes
1answer
114 views

Understanding distribution chart

How to explain DistributionChart function in mathematica, For example: if I have ...
2
votes
1answer
158 views

Judging the quality of fitting an EventData object to a distribution using LogRankTest

I have $389$ data points defined in an EventData object and want to judge the quality of fit of this data to a fitted $3$-parameter Weibull distribution. This ...
3
votes
1answer
119 views

How to Use ProbabilityScalePlot with Censored Data?

I am trying to reproduce a ProbabilityScalePlot of censored data shown here (see Sample Analysis Plot). Here is my Mathematica code. First I deal with the uncensored case. ...
7
votes
1answer
98 views

Why does Rescale performance vary significantly based on the real number values in a list?

I have a list of the form: testList = Table[{Flatten[RandomReal[{-200, 200}, {1, 2}], 1], RandomReal[{-200, 200}, {69, 2}]}, {i, 1, 100}]; And I would like to ...
4
votes
2answers
296 views

How to exclude some points to make them more evenly distributed in a figure

If there are some points in a figure, how can I exclude some points to make them more evenly in the figure? 'Evenly' here can be defined as the number of points in each $0.01*0.01$ box is at most one. ...
10
votes
5answers
388 views

Relational joining of tables

A common thing to want to do with data is to combine it (at least I thought this was a common thing). In SQL there is the idea of table joins "select id,v1,v2 from A,B where A.id=B.id" kind of thing. ...