# Questions tagged [numerical-value]

Question relating numerical representations, operations and methods, including approximate results instead of exact symbolic results.

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### Prime sign ` followed by numerical values [duplicate]

Here are 2 lines of the numerical output of Mathematica: -0.0021055211287945152282575757575757575812.493743372412704 0.0282098170963017582537878787878787878913....
1 vote
1 answer
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### Techniques to solve complicated simultaneous equations

I want to solve 5 equations simultaneously for 5 variables (N2[t],TT[t],PP'[t],SS'[t],z1'[t], code attached at the end of the post). The equations are extremely long and complicated. I have tried ...
3 votes
0 answers
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### What's the best method to use when NIntegrating a sinx + cosx type function?

I'm having some problems when trying to NIntegrate a sinx + cosx type function. I have already tryed several combinations of ...
2 votes
1 answer
61 views

### NSolve Having No Output

I am trying to solve a series of equations using the NSolve function, but am receiving no output. I tried to make the equations into a single equation, but this also doesn't work. I was hoping for ...
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1 answer
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### How to numerically integrate with unknown coefficients?

will it be possible that I could integrate the equations like the following with unknown parameters M and h? I find it really hard. Any advice will be really appreciated, thanks. ...
1 vote
2 answers
106 views

### ParametricPlot3D Curve and ImplicitRegion: Projections and Intersections

There is a parametric 3D-Curve: ParametricPlot3D[{Sin[t], Cos[1 - 3 t], Sin[2 t - 1]}, {t, 0, 10}, BoxRatios -> {1, 1, 1}, AxesLabel -> {x, y, z}] And ...
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3 votes
1 answer
176 views

### Solve an equation

I have this equation in terms of x0 and I need to find x0 in terms of Theta . ...
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1 answer
77 views

### Nature of function as $x→∞$ [closed]

I'm studying the limits and applicability of Abel Plana summation for different test functions (class of functions). In doing so this just pops out and couldn't handle the said integral so asked here (...
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1 answer
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### How to obtain the convolution of these functions?

I am starting to use Mathematica. I wanted to compute $$\nabla F*\phi(x),\;x\in\mathbb{R^2}$$ where $F(x)=\ln\|x\|$ and $\phi(x)=\chi_{B(0,2)}(x)$. I am a new user of this software, so I don't know ...
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1 vote
3 answers
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### Is the result given by NSolve sufficiently reliable to claim that there is such a solution for the equation?

I use this code for ContourPlot ...
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2 votes
2 answers
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### Optimising eigenvalue matrix calculation

I'm quite new to mathematica and am trying to figure out how to optimise my code as currently it takes a very long time to compile and makes it hard to bug test. The first part that creates the graph ...
1 vote
2 answers
91 views

### NSolve and FindRoot give a value which is not correct; how can I obtain the exact solution of the given equation? [closed]

I have two functions $f(x,y)$ and $g(x,y)$, I use this code ...
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1 vote
1 answer
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### Why the substraction of two big numbers does not yield 0, but taking their quotient yields 1?

I have two series, generated as, ...
-2 votes
1 answer
150 views

### How to split data in a matrix

Consider the matrix 'm1' : m1 = RandomReal[{0, 1}, {50, 50}]; MatrixForm@m1 The partition of this matrix into non-overlapping rectangles (arranged horizontally) ...
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1 vote
1 answer
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### NSolve for Piecewise function

I have a piecewise function. I want to find the root of this function with the NSolve command. But, it does not give me any result and it just prints the equation. I can find the root with FindRoot, ...
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### How can I make sure if the given function has any roots which are not rational multiples of $\pi$?

I have this function for $0<x<\pi$. f(x)=(3 \pi -2 x)^2 \sin \left(\frac{1}{2} \left(\csc ^{-1}\left(\frac{4 \pi (\pi -x) \csc \left(\frac{\pi ^2}{\pi -x}\right)}{4 x^2-8 \pi x+5 \pi ^2}\...
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### NMaximize computes wrong value

This question is a continuation of NIntegrate with a complicated function over the 4-sphere . Now I define a certain new function called "improvement" via: ...
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92 views

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1 vote
1 answer
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### Phenomena between ill-conditioned and well-condtioned

Given that I have the following sparse matrix: ...
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1 vote
1 answer
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### how we can extract the value of the solution of a PDE in a point x? (NDSolve) [closed]

Please I need your help, I calculate the solution of heat equation using methode of line This is my code: ...
0 votes
1 answer
35 views

### Indeterminant numerical value of summation

I have the following two-fold summation. ...
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2 answers
62 views

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### (Urgent) NSolve not working and visualization of solutions

I want to solve a system of three equations and 3 variables numerically with NSolve, but it either takes an eternity and doesn't give me a result or it gives me an error message that the methods ...