Questions tagged [numerics]
Questions on the numerical functions of Mathematica, implementing numerical methods and numerical computing with Mathematica.
2,294 questions
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Numerical errors in NSum for $\sin(\sqrt{k})/k$ series
I'm encountering numerical accuracy issues when computing the infinite series:
NSum[Sin[Sqrt[k]]/Sqrt[k], {k, 1, β}, WorkingPrecision -> 20]
Despite setting <...
- 63
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50
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FindRoot inside FindRoot sometimes not working
I was trying to find the root of a function which is in-turn given only by the solution of FindRoot. The following does work for some values. For others it produces the same error as without the ...
- 322
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How to syntax products and append each result to a table?
I'm still trying to learn how to code the results of the LHS and RHS of this famous equation into a table:
$$\sum_{n=1}^\infty \frac1n=\prod_{i=1}^\infty\frac{1}{1-\frac{1}{p_i}}\tag{A}$$
I asked this ...
- 171
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How to output results of the sum, $\sum_{a=1}^2\sum_{b=1}^a\sum_{c=1}^b 2^a3^b 5^c$ into a list (table)?
I'm trying to write a code that can approximate the following formula,
$$\sum_{n=1}^\infty \frac1n=\prod_{i=1}^\infty\frac{1}{1-\frac{1}{p_i}}\tag{A}$$
In this M.SE question I was convinced that $(\...
- 171
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"Glueing" interpolating functions
Suppose we have two interpolating functions with exactly touching domains, in our case {-1, 1} and {1, 2}.
How to "glue&...
- 30k
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139
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How to output each summand of $\sum_{n=1}^k \frac1n$ into a list?
From real analysis, I'm trying to learn more about this famous equation in this post of Mathematics.SE:
$$\sum_{n=1}^\infty \frac1n=\prod_{i=1}^\infty\frac{1}{1-\frac{1}{p_i}}\tag{1}$$
I won't ask ...
- 171
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4
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Using NDSolve to solve three coupled ODEs
I am trying in this code to solve three non-linear ODEs together, and I want to plot the three functions as functions of Ξ·.
Why does my code not work?
...
- 81
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Error in Lyapunov Exponent
I want to calculate Lyapunov exponents for by varying two parameters so that I can get density plot.
I am using the code:
...
- 313
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1
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Solving enormous linear systems [closed]
On an assigment on numerical analysis, i'm asked to solve some linear systems of order 200x200. However, neither the function LinearSolve nor the LU decomposition run in a reasonable amount of time. ...
3
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How do I set up a recursive algorithm to repeatedly square root a positive real number?
From real analysis, I was asked the following question:
What happens when you hit the square root key repeatedly on a calculator for any initial positive number $x$? Formulate this question in terms ...
- 171
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229
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Error on numerical integration
Is there a way to obtain the error on a numerical integration using NIntegrate ?
I have try this answer https://mathematica.stackexchange.com/a/102469/111297, ...
- 21
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Determinant with numerical value and Working precision
I have a matrix, with entries are series with numerical coefficients
$$
\begin{pmatrix}
G(q) & F(q) \\
F(q) & G(q\rightarrow-q)
\end{pmatrix}
$$
With $G(q)$ is an expansion obtained with <...
- 21
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How to reduce the size of the output `InterpolatingFunction` from `NDSolve`? [closed]
This is my codes to calculate a wave equation by NDSolveValue:
...
- 2,360
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How can I construct a column vector of n components? [closed]
I have an equation to determine the elements of a vector y of n components, as shown in the image below.
I would like some help on how I can make a program in Mathematica that numerically solves the ...
3
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2
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393
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Double optimization - function defined through `Module`
I am solving an optimization problem where there is an energy defined with some functions and some fixed parameters. I define this minimum as function of two variables and want to search in the space ...
- 712