0
votes
0answers
8 views

Asymptotic solution

I have an ODE V''[z] + ( (I z0^2 w)/(3 (z - z0)^2) + ( 2 - (4 I z0 w)/9)/(z - z0)) V'[ z] + (-(12/41) I z0 w + (23 z0^2 w^2)/ 369)/(z - z0)^2 V[z] == 0; ...
0
votes
0answers
9 views

Improve speed of Nested Matrix exponential

I have a short Code example and I want to know whether it is possible to improve the speed. The L matrix in my code is a SparseMatrix, but for this question I just use something similiar. ...
1
vote
0answers
10 views

Changing coordinates or rotating finished 3d Graphics

I have created a 3d graphics consisting of three parts and I would now like to take the entire result and rotate it. Here is the code so far: ...
0
votes
0answers
13 views

averaging over large number of random realizations

I want to run following for few hundreds of a random variable set. This calculates: generate normal random variable find gain with squaring calculate performance metric find ...
0
votes
0answers
21 views

why the result not contain imaginary, I?

Good day, First of all, sorry if my coding in this forum has mistake. I already learned it and this is the best try from me. May anyone help me troubleshoot my problem below. ...
0
votes
0answers
25 views

Why does the replacement /. {1 -> x} make sense?

Why does the replacement expr /. {1 -> x} in which the number 1 is replaced by the symbol ...
0
votes
1answer
28 views

2D Plot for PDE

I made scheme for diffusion equation And I know how to make Plot3D But how to make Plot2D with different time? ...
0
votes
0answers
34 views

A question about structure of if-else

I have coded this program in Mathematica but I am not sure to make correct structure of if-else. Is anyone able to present guidelines in a way that error of program was not met? ...
3
votes
1answer
45 views

Partitioned Matrix in Display Form in a Notebook

Consider: $$A=\left[\begin{array}{rrr|rr} 2 & -3 & 1 & 0 & -4\\ 1 & 5 & -2 & 3 & -1\\ \hline 0 & -4 & -2 & 7 & -1 \end{array}\right]$$ Let's say I am ...
0
votes
0answers
24 views

How to do feature extraction

I have some images and I'd like to find generate features to compute a similarity metric. What is the Mathematica way to do this?
5
votes
2answers
65 views

Adding arrows in Tangent

I want to add arrows to the start and the end of the Tangent curve. My first try was successful, ...
2
votes
3answers
103 views

Table with condition

I have 2 lists of numbers A = Range[16, 65] and B = Range[10, 16]. I want to form all possible combinations $(a,b)$ of the ...
0
votes
0answers
32 views

Sorting Ordered List of Words by First Letter

I am trying to sort an ordered list of the most common Arabic words. I want to create sublists of words according to their first letter while maintaining the order of the original list. Here's an ...
0
votes
0answers
10 views

Multiple plot for 2 variables function [duplicate]

I have a 2 variables function as below: m[n_] := 1.5 n^2 V[n_, r_] := (m[n]*m[n])/((r)^3) On the range of r from 1 to 20 I want to make 30 plot (30 different ...
0
votes
0answers
26 views

3D listplot, for a given table

I have a table of 4 data, my first problem is how can I choose one region in which just one of these variables is constant and the listplot3D the other 3 variables? I need to do this for at several ...
5
votes
3answers
102 views

How to label ticks in ListLogLogPlot in scientific form in MMA 10.4?

This is a question regarding ListLogLogPlot in MMA 10.4. I have tried the solutions suggested in 5369, and they do not appear to work in MMA 10.4, so I would be grateful if this could be considered a ...
2
votes
1answer
15 views

I have a communications link failure with JDBC MySQL(Connector/J)

I am unable to connect to my local mysql server using Mathematica. ...
0
votes
0answers
18 views

Vector in 3D Spherical Coordinates [duplicate]

How do I plot a list of spherical co-ordinates in (of course) 3D Spherical Co-ordinates. As arrow headed vectors, preferably. The list is: ...
2
votes
2answers
60 views

Problem using ArcTan inside NDSolve

I'm messing around a bit with using "thrust segments" on a point-mass in NDSolve and have run into a strange problem to do with using ...
0
votes
0answers
46 views

How to implement multiple EventHandlers?

n00b Mathematica user here. I wrote this code: ...
1
vote
1answer
42 views

Using TemporalData`DropTimes

I'm not able to figure out how the undocumented command TemporalData`DropTimes described here works. For example, I have ...
3
votes
0answers
30 views

Automatic legend does not include all datasets in case of short list of colors

The following code gives legend only for elements with unique color ...
0
votes
0answers
21 views

Get rid of infinty in matrix elements (by seperately defination of diagonal and off-diagonal elements)

I want to generate a matrix in which the elements have the below rule to be generated: ...
3
votes
2answers
47 views

Using Dataset with TimeObjects in EventSeries

I'm new to Mathematica, and while this is potentially quite easy, I'm having difficulty using TimeObjects in the EventSeries ...
1
vote
1answer
47 views

Do-Command around entire Notebook (by iterating it from another notebook?)

I have a large simulation (1500 lines of code in different sections) and I would like to run the file using different combinations of input parameters without manually changing the parameters. Say my ...
1
vote
1answer
46 views

Dynamic and TabView mayhem

What I'm trying to do is damn simple but it seems like Mathematica is extremely ill-designed for this ... Here is a very simplified form of my code to show the basic idea. I have a variable number of ...
5
votes
2answers
51 views

How to create a window which will close in a certain amount of time?

I'm currently making an interface in Mathematica and I'll need to bump a window out and then let it close itself in a certain amount of time. Here's an short example to illustrate the effect: ...
0
votes
0answers
20 views

NDSolve: Improperly assigned stepsize

This is not a question which I estimate is aided in answering by providing complete code, which is excessively long. I ran an NDSolve[] at ...
3
votes
1answer
81 views

Speedier Algorithm or Set of Steps to Increase Speed of Coefficient Generation

Good morning. I am working with higher powers of the Generalized Euler Number generating function $$\left[\frac{n}{\sum_{j=0}^{n-1}\exp{\left(w_n^jx\right)}}\right]^\alpha$$ where $w_n=\exp{\left(...
1
vote
1answer
44 views

Timeseries Analysis. Calculating Returns, Correlations between timeseries data and overlapping data

I have a set of sample time-series data below of monthly prices for two companies. Q1. I want to calculate monthly and quarterly log returns.what is the most expedient way to do this? ...
3
votes
1answer
100 views

Is it possible to simulate a solved example in Wolfram for free, How?

How we can write the following Formula in Wolfram: The Fourier Series $$ f(x)=f(x+2\pi), f(x) =\left\{ \begin{array}{rcr} 1 & & -\pi <x<0 \\ \sin x & & 0<x<...
10
votes
3answers
587 views

Generate a certain colorful triangle

I want to get a colorful triangle like this: I hope to get a triangle with any number of layers. This is my current method. Actually, I'm not very content with these graph theory functions, since ...
4
votes
1answer
81 views

Better use of pattern matching in replacing elements of a list

I have a list of reals and I'm replacing those which are contained in a given interval with two different values depending on wheter the selected reals are positive or negative. I came up with this ...
0
votes
1answer
34 views

Frameticks in RegionPlot [on hold]

I have an issue with frameticks in region plot. Look at the code ...
-1
votes
0answers
52 views

Why is result from evaluation not simpler? [on hold]

How do I define variables $\qquad u(x_m , y_n)\qquad m,n=1,2,\dots,4$ in Mathematica? $x_m, y_n$ are known and $u$ is unknown. The result I am getting is: ...
2
votes
0answers
50 views

Removing plot artifacts (SphericalPlot3D)

Using SphericalPlot3D, I find I get two types of artifact: A discontinuity in the surface reflectance at $\theta=0,2\pi$ Little edges, or perhaps gaps between ...
0
votes
0answers
32 views

NDSolve and piecewise functions

I'm trying to use NDSolve on a Pde for a function that is made up of several pretty complicated functions, most of which are themselves functions of an underlying piecewise function. When I try to ...
1
vote
2answers
78 views

how do I control the output of Reduce function?

Reduce[x*y > 50 && x*y < 100 && x < 100 && x > 1 && y > 1 && y < 50, {x, y}, Integers] what if I want ...
8
votes
0answers
58 views

Bug with Compile and Log2?

It seems that Log2 in Compile gives numerical errors (CompiledFunction::cfn) if the input is ...
7
votes
2answers
82 views

Efficiently checking whether a number is a perfect power

Goal The goal is to efficiently check whether a number is a perfect power. Attempts It is possible to check whether a number is a perfect power using ...
1
vote
1answer
53 views

Expectation of Largest Roots of Bernoulli distributed coefficient Monomials

I am interested in determining the most probable maximum values of the real roots of polynomials of form $P(x)=\sum_{k=0}^n a_{k} x^k$ where the degree $n$ will have a defined value (say 3,4,5...) and ...
0
votes
0answers
29 views

Do you know the options of RandomSeed in ClusteringComponents? [on hold]

ClusteringComponents[data, 4, 1, Method -> "KMeans", DistanceFunction-> EuclideanDistance, "RandomSeed" -> 10] As above, 4 means cluster number, ...
1
vote
1answer
73 views

Substutution of Ansatz of an ODE [duplicate]

I am only beginning to learn to use Mathematica, and got stuck while trying to implement what is apparently a simple substitution rule. So I have a second order ODE in f, and I want to put in the ...
0
votes
0answers
43 views

Error message when using Method -> “Spline” in Interpolation [on hold]

I'm using LTNOspline = Interpolation[DiscreateLT, Method -> "Hermite"] where ...
2
votes
2answers
91 views

How to find Eigenvalues of Sturm-Liouville problem? Getting wrong Imaginary Eigenvalues

I want to find Eigenvalues of following Sturm-Liouville problem D[(2 - MA/κ[s]) q'[s], s] + W Ω^2 q[s] == 0, Where Ω^2 is the ...
0
votes
2answers
38 views

TimeSeriesAggregate—reformatting the date

Compute Aggregated Statistics for a Time Series The article linked to above provides a sample of aggregating time series data. ...
3
votes
2answers
98 views
0
votes
2answers
33 views

Read timeseries data from CSV

I am new to Mathematica and have v10. I would like to you use the new TimeSeriesAggregate[tsdata, "Quarter", Total] feature to return aggregated descriptive stats. I import a number of columns of ...
0
votes
0answers
3 views

Maximum Likelihood Approach for parameter estimation of multi response data, could you provide a tutorial? [migrated]

I was trying to fit the parameters a time dependent system coupled of ODES relate to a kinetic experiment with multi response data. example: A->B+H A+H->C+H A->D dcA(t)/dt=-k1Ca(t)-k2Ca(t)*Ch(t)-k3*Ca(...
-2
votes
0answers
28 views

Plotting Graph having coloured visuals and coloured lines [on hold]

Somebody please tell me what is "fondo" and "funcero" Plus I'm having a great difficulty in plotting a graph, my graph line doesn't show up. frustrated

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