Questions tagged [assumptions]
Questions about the function Assuming[], the $Assumptions system variable, and the Assumptions option of functions such as Simplify[] and Integrate[].
545
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Simplifying Min with assumptions
Lots of ecological models use Liebig's law of the minimum when multiple essential resources may limit growth. I want to break these equations into the special cases using ...
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1
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Specifying properties of a function as assumptions
I am trying to simplify expressions involving a function $f: \mathbb C \to \mathbb C$ which satisfies
$$f(-z) = -f(z), \quad f(z^*) = f(z)^*, \quad \forall z \in \mathbb C.$$
I do not want to specify ...
- 143
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0
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Is there a way to force 'Simplify' to use some assumptions?
First time poster. I have a basic question about 'Simplify'.
I am encountering a problem when trying to simplify some algebraic expressions, where I find an unexpected behaviour of the 'Simplify' ...
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1
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Assuming[a ∈ Reals, Conjugate[a]] fails to invoke assumptions [closed]
Miminmal working example:
Assuming[a ∈ Reals, Conjugate[a]]
Returns Conjugate[a] instead of ...
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Puzzling behavior of `Assumptions` in `Solve`
With Wolfram Language 13.3.0 Engine when solving the following equation:
...
- 307
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1
answer
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Tell Mathematica that the output of a function is a List / Vector
I have a function (Piecewise) that returns a list, e.g.:
F[x_] := Piecewise[{{{x^2, x}, x < 0}, {{x, x^2}, x > 0}}, {0, 0}];
I would like to add another list ...
- 327
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2
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Why is Assuming[...] ignoring the assumption?
Let's say I want to compute a quantity like $e^{i \pi \vert \vec a \vert}$, and for a certain vector a = {a1,a2,a3} I assume it has length 1, so the quatity would ...
- 95
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Simplify matrix expression with assumptions
I am trying to simplify complex matrix expressions with some assumptions (such as matrix is a rotation matrix). I am failing to do it properly. Find below the simplest example that reproduces the ...
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Check positivity with additional conditions
I am completely new to Mathematica. I would like to check when
$$
\frac{1}{2ka}\left(\sqrt{b}x-\frac{z}{\sqrt{b}}\right)^2+\frac{1}{2mb}\left(\sqrt{a}y-\frac{z}{\sqrt{a}}\right)^2+\frac{1}{2c}(bx+ay-z)...
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Which of the given codes $p1,p2,p3,p4$ is the correct one for imposing assumption in ContourPlot3D using RegionFunction?
I am using ContourPlot3D for the condition f[x_, y_, z_] ==0 assuming that the assumption ...
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How to compute this integral $\int_{-\frac c2}^{0} e^{-a \left(\frac{b x^3}{2}-\frac{x^2}{4}\right)} dx $? [closed]
I want to compute this integral:
$$ \int_{-\frac c2}^{0} e^{-a \left(\frac{b x^3}{2}-\frac{x^2}{4}\right)}
dx \qquad\textstyle{with}\qquad a,b>0 \qquad\textstyle{and}\qquad a,b\in\mathbb{R}$$
The ...
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0
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Why is -1 raised to an odd power different from -1? [closed]
In the following code, shouldn't the result be -1? It doesn't give me anything. Why?
Assuming[Element[n, OddQ], (-1)^n]
Thank you in advance.
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How to plot the given functions $g$ and $h$ with the assumption $f=0$?
I have a constraint f[a_, b_, c_] ==0 with three parameters $0<a,b,c<3$ where
...
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151
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How to assume a function is holomorphic?
For example, for a holomorphic function $f(z)=f(x,y)$, it's well know that $\ln |f|$ is harmonic. I want to check it with mathematica with the following code:
...
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