Questions tagged [inverse]
Questions on exact, symmetric reversal of a definition or functional mapping (i.e. the original form is returned when applied twice). Use this tag for issues on inversion of Mathematica expressions, or general inversion of math constructs.
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FourierTransform and InverseFourierTransform are not inverses when using non-default FourierParameters
FourierTransform and InverseFourierTransform are inverses of each other when using the default ...
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How can I find an inverse function of solution from NDSolve?
I have the following code.
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Simplify inverse of function
This would be a noob question, but I need help simplifying the inverse of an expression
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How to accelerate Inverse[] for positive definite matrices symbolically?
I am trying to construct a positive definite matrix based on the multiquadric radial basis function (RBF) for a set of thirteen points symbolically in order to later approximate the Laplacian operator ...
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InverseFourier, Time response from the pressure over frequency
the problem I'm trying to solve is much more involved, that is I'm trying to get the Time Response for an Impulse Input for a loudspeaker starting from the pressure it generates over the frequency:.
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Looking for the asymptotics of an asymptotics
I am trying to polish my second answer to this question in Mathematics Stack Exchange.
The problem is to find the asymptotics of $t$, solution of the implicit equation
$$\color{blue}{\left(1-2 x^2\...
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Newton method and Armijo-Goldstein
I need help with my project. I have three nonlinear systems and I need to write a code for Newton methods and Armijo-Goldstein and see the differences.
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Numerical solution of the inverse contour plot
I have a function $f(u,v)$ on some domain of $(u,v)$ and would like to find (numerically) the set of couples* $(u_0,v_0)$ s.t. $f(u_0,v_0)=0$, for instance (just and example to illustrate, in practice ...
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Asymptotic inverse function?
A paper I am reading defines a variable $\theta$ in terms of another variable $\phi$ as an expansion in $u$, where $u$ is understood to be small:
$$\theta=\phi-u^2\sin\phi+\mathcal{O}(u^4).$$
They ...
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How to get more terms with the Series[] expansion of InverseErf[x] around x=1?
The inverse error function, which is given by InverseErf[x], is quite important in statistics as it gives the confidence levels around a 1D Gaussian, for example ...
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How can I find the inverse of an interpolating function?
I am numerically solving the coupled differential equations (for $t[\tau]$ and $r[\tau]$) below. Mathematica outputs two interpolating functions as solutions. I would like to invert one of these ...
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Inverse function of y = x + (0.022 - x) ^ 1.414?
I'm a software engineer with math classes through differential equations about 15 years in my past, and I've gotten stuck trying to invert an equation.
The equation:
$y = x + (0.022 - x)^{1.414}$.
In ...
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Invert a generic n x n matrix
I want to invert a generic n x n matrix. Is it possible to do this with Mathematica?
Consider, as a minimal example, the $n\times n$ matrix:
\begin{bmatrix}1n&0&...&0\\0&2n& ... &...
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Variation with respect to inverse metric in a Lagrangian density
I am trying to vary the following Lagrangian density
with respect to the inverse metric appearing in the equation, but I am having trouble with how to write the right code in Mathematica.
I have ...
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