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What class order should I use to study calculus?

I would like to know how I should go about studying calculus, and in what order should I take the classes. I have searched tirelessly for answers and I am still confused. Here is what I have gathered ...
1
vote
1answer
6 views

Select a subsequence of a sequence according to tosses of a biased coin

I have a sequence, from which I would like to select a subsequence, each term of the original sequence being included in the subsequence with probability $p$, independently of the other terms. That is,...
0
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0answers
21 views

Symbolic integration and simplification in Mathematica

I am using Mathematica for the very first time, to evaluate the following integral, but I am not getting an answer. What is wrong with the script My code: ...
0
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0answers
15 views

How to fix EdgeWeights when a vertex is deleted from a directed graph (BUG?)

I have the following Codes (developed by @Mr.Wizard and @kglr, respectively): ...
1
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0answers
14 views

Computing the set of automorphisms of a non-simple AND multi-graph?

As the title says, we would like to compute the set of all isomorphisms between, possibly, non-simple directed multi-graphs. A related question is How to compute the automorphisms of graphs with ...
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0answers
29 views

Can a plotted graph be included with a Tooltip?

I have a set of spectral training data for 2 thousand plus colors. Right now each color can be compared with a result a ListLinePlot made to show both on a graph with RMSE. I would like to be able ...
1
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1answer
26 views

Comparing two equivalent definite integrals

Reading this question on Math.SE, I tried the following Mathematica instructions ...
0
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0answers
43 views

Why is there no heat being transfered in my program?

I have been working on this code and am new to this coding language. I have been trying to model the transfer of heat through a hot plastic being cooled in a water bath. For some reason I have not ...
2
votes
2answers
88 views

Finding closed or numeric value for $\int_0^{\infty } \frac{x \csc (a x)}{x^2+b^2} \, dx$

According to Gradshteyn 3.747-3 $\int_0^{\infty } \frac{x \csc (a x)}{x^2+b^2} \, dx=\frac{\pi}{2\sinh(ab)}$ $b>0$ so I'm trying to get some numeric results from Mathematica 12. ...
1
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1answer
31 views

matching Inequalities

Consider the following list list={0 < x < 1/12, 0 < x < 1/4} I wish to find the intersection of the two ranges of x ...
6
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2answers
53 views

The numerics of FresnelS[]

Bug introduced in 12.1 or earlier and persisting through 12.1.1 or later [CASE:4615361] Note: A worse problem existed in 12.0 for inputs greater than 8 and of ...
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0answers
39 views

Missing integration constants in solution to PDE

I am attempting to obtain the analytical solution (if possible) to the following: $$a w^{(1,0)}(x,t)+b w^{(0,1)}(x,t)=p(x)+g w(x,t)$$ $$I.C.: w(x,0)=0 | B.C.: w(0,t)=z(t)$$ ...
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0answers
19 views

Creating .wmv file using MathMF

I am trying to create a movie (.wmv file type) in Mathematica using MathMF. Here is my code: ...
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0answers
27 views

Error with Multiselection on ListPicker [closed]

I am unable to multiselect on the ListPicker, even on the examples in the documentation. It just single selects instead. I am using Version 12.1. Has anyone else ...
2
votes
5answers
217 views

How to solve this analytic geometry problem completely

I want to find a plane that passes through points {1,0,0} and {0,1,0} and is tangent to surface $z(x,y)=x^{2}+y^{2}$. ...
2
votes
1answer
43 views

How to get the modulus of two functions

I might be overlooking something, because what I want to do is quite elementary. I want the following term Mod[2(1 + z), (1 + z)] to evaluate to ...
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0answers
27 views

How to judge whether a single-variable function is differentiable at a certain point

Michael E2 solves the problem of differentiability of multivariate functions. ...
0
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0answers
31 views

Problem with MATLink use with Mathematica

After installing MAThLink I started its use in Mathematica: Needs["MATLink`"] CommandWindow["Show"] OpenMATLAB[] I got the following output: <...
8
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1answer
93 views

How to find a numerical antiderivative with NIntegrate methods?

@JimBelk asked in Interpolating an Antiderivative how to find a numerical antiderivative. I gave an answer that uses NDSolve with the default method for integrating ...
0
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0answers
20 views

How to solve this equation with matrix rank condition

It is known that quadratic form $f\left(x_{1}, x_{2}\right)=x_{1}^{2}-4 x_{1} x_{2}+4 x_{2}^{2}$ can be transformed into quadratic form $g\left(y_{1}, y_{2}\right)=a y_{1}^{2}+4 x_{1} x_{2}+6 y_{2}^{2}...
2
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3answers
119 views

RandomPoint fails for any higher dimension

region = ImplicitRegion[x^2 + y^2 + z^2 + p^2 == 1, {x, y, z, p}]; RandomPoint[region] The result is RandomPoint[ImplicitRegion[x^2 + y^2 + z^2 + p^2 == 1, {x, y, z, p}]],and how can I attain two ...
9
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1answer
139 views

How can I find a functional square root in Mathematica?

A functional square root of a function $g$ is another function $f$ such that $g=f\circ f$. According to that article, there is a systematic approach to finding a functional square root that involves ...
0
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3answers
60 views

How to solve the approximate value of this probability problem

It is known that X1, X2,...,Xn are random samples from the population X, where the probability of X taking 0 or 1 is equal, that is, $P(X=0)=P(X=1)=\frac{1}{2}$. I want to find an approximation of $P\...
0
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0answers
50 views

Is financial visualization broken? Can you run any of these examples or InteractiveTradingChart[] at all?

I can't run anything relevant to financial visualization in my mathematica installation, i found these interesting example but anything that use the trading chart is kind of broken. EDIT: I'll add a ...
0
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0answers
35 views

How to activate Manipulate controls

I have two notebooks NB1 and NB2. In NB2 I perform the following symbolic calculations: <...
0
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1answer
58 views

Imprecise 3D plot

I'm plotting the following figure: There are two issues: There is some noise around the edges of the section of the torus, see figure below The torus is not smooth enough (modulo rasterization of ...
0
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0answers
38 views

Problem Loading a Plot with FormPage

I am using FormPage to generate a DateListPlot with the TimeSeries of "ConfirmedCases" by Country. The code which I am using is ...
2
votes
2answers
58 views

Adding z-value to mesh lines in Plot3D

I'd like to label the level curves of a scalar field according to their $z$-value. The below code (taken mostly from this answer to a very similar question, but which uses tool-tips instead of ...
0
votes
3answers
45 views

NMinimize: How to avoid solutions that do not satisfy constraints within a certain tolerance?

I just started to use Mathematica a few weeks ago. Using NMinimze, I would like to avoid solutions that do not satisfy certain constraints (although they "almost" satisfy them). Do you know ...
1
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0answers
34 views

problem facing while solving a coupled differential equation [closed]

I am trying to solve coupled differential equations, inside which I have a function which I am getting by doing NIntegrate. The code is shown below: ...
8
votes
1answer
657 views

How to enter a nuclear reaction?

Sometimes the simplest things are the most difficult, I need to make a presentation, and I thought to do it in Mathematica, I wanted to do a demonstration too, well...this is the Rutherford's equation ...
1
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0answers
61 views

Why Does Subsets[…,{n}] Unpack?

Assume list is packed. I expect Subsets[] is a structural operation because it depends on the number of elements, not on what ...
0
votes
2answers
56 views

How to calculate the second-type curve integral

I want to calculate the second type curve integral $I=\int_{L} \frac{4 x-y}{4 x^{2}+y^{2}} d x+\frac{x+y}{4 x^{2}+y^{2}} d y$, where $L$ is the curve $x^{2}+y^{2}=2$ (the direction is the counter ...
1
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1answer
65 views

Parameter estimation using LogLikelihood

I'm trying to understand Likelihood methods with parameter estimation in mind. To this end I am trying to construct small examples that I can play with. Let's say I have some data which I know (or ...
5
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2answers
146 views

Remove mesh triangles in contour plot

How do I get rid of the mesh in this contour plot? ...
0
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0answers
61 views

How to eliminate the list case by `Eliminate` function

It is known that line L1: $\frac{x-a_{2}}{a_{1}}=\frac{y-b_{2}}{b_{1}}=\frac{z-c_{2}}{c_{1}}$ and line L2: $\frac{x-a_{3}}{a_{2}}=\frac{y-b_{3}}{b_{2}}=\frac{z-c_{3}}{c_{2}}$ intersect at a point. Now ...
2
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1answer
62 views

How to control the output of Polygon

In the documentation article for Polygon in Mathematica 12, there is an example with the input: ...
-1
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0answers
43 views

check if a string is an element of a list of strings

I have a list of strings called words. I'm writing: "cat" [Element] words I was hoping to get a True/False output, but I just get the input returned to me. This is the output regardless of ...
1
vote
0answers
63 views

Integration that involves inverse of a big symbolic matrix

I have a $300\times300$ symbolic matrix and I want to calculate its inverse matrix. It has been two days and Mathematica is still executing Inverse[T]. $T$ is the name of that matrix. Why am I ...
0
votes
2answers
53 views

How can I make sure that the plot of this function cross each other or not?

I have this function: $$\frac{1}{16} \left(\sinh (\pi x) \left(64 \left(x^2-4\right) \cosh \left(\frac{2 \pi x}{3}\right) \cos (y)+\left(x^2+4\right)^2+256 x \sinh \left(\frac{2 \pi x}{3}\right) \...
0
votes
1answer
53 views

How do I reflect changes to the intensity values in the 3D Shepp Logan data visualization?

I have been doing a self study on the 3D Logan Phantom developed by CG Koay and research group. A mathematica notebook from this group is available here. The codes present a 3D visualization of a ...
1
vote
0answers
45 views

Maximize taking too long

I just started to use Mathematica a few weeks ago. I am afraid there is something that does not work on my laptop because, for the following simple command, it takes too much time. Do you know if ...
0
votes
0answers
25 views

Finding the right amount of exposure to a bundle of stocks mathematically [closed]

Let's say I have a bundle of 50 stocks and I can make 20 portfolios with 5 stocks in each portfolio. Each stock has an average price, a projected price, and a probability of hitting said projected ...
0
votes
0answers
28 views

How do I replace ticks of a DiscretePlot3D by substituting $x$ with $2x+1$ without changing or scaling the chart other other axes?

I just want to replace the tick labels of the x-axis ("v1"). Each label $x$ should be replaced by $2x+1$. For example instead of 0 there should be a 1 and instead of the 19 there should be a ...
2
votes
1answer
36 views

Limit of multivariate piecewise function

Let's say we have a multivariate piecewise function f[x1_,x2_]:=Piecewise[{{Sin[x1]/x1,x1>x2},{Sin[x2]/x2,x1<=x2}}] Now we want to determine the limit in f(0,...
0
votes
1answer
34 views

How to define a function to decouple equations and transform them into standard form

I want to convert this expression($\frac{x-a 2}{a 1}=\frac{y-b 2}{b 1}=\frac{z-c 2}{c 1}$) of the linear equation into a standard form $\left\{\begin{matrix} \text { b1 } * x-a 1 * y=a 2 * b 1-a 1 * ...
1
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0answers
38 views

Collecting terms in NCAlgebra

Let's say we have GP[v],GM[v]: two noncommutative objects depending on the commutative variable v. ...
0
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0answers
25 views

Reduce does not solve a system of equations

I am trying to solve a system of 7 equations and 7 unknowns given a set of assuptions. I am only interested in obtaining V3 as a function of the exogenous parameters. I am using the following code: <...
1
vote
0answers
96 views

System of 15 equations in 23 variables

$$ 1-k_0^2=0, \frac{1}{2} \left(-7 \alpha ^2+38 \alpha +2 c_3 (\alpha +\beta-3)+2 c_6-2 k_1^2-2 k_5^2-48\right)=0, c_5-k_2^2-k_{10}^2=0, c_8(\alpha +\beta -5)+5 c_{10}-k_3^2-k_6^2-k_8^2-k_{11}^2-2 k_2 ...

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