All Questions
Tagged with numerical-value functions
27 questions
0
votes
2
answers
170
views
How to numerically find complex non-real roots of a function?
Using Mathematica, how can we numerically find only complexes, but not real roots, of a function?
For example, if we have f:C->C, and we have roots like, R1,R2,...,Rn (real roots, without imaginary ...
- 1,536
1
vote
1
answer
70
views
Value given by NIntegrate is double of Integrate function
I am performing a calculation where the result of NIntegrate and Integrate is different. They differ by factor of 2. Can someone tell what is the reason and how to make the NIntegrate value right?,
<...
- 194
1
vote
1
answer
94
views
Equality contraint violated with NMinimize
I am attempting to numerically optimize a function of only 2 parameters k, θ. There are two inequality constraints (1 each on k ...
- 1,007
1
vote
2
answers
141
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NMinimize keeps returning Indeterminate for well defined function
I am attempting to numerically optimize a function of only 2 parameters k, \[Theta].
The function is well-defined and the constraints are simple. However, the ...
- 1,007
1
vote
0
answers
74
views
The result of interpolating a table is not numeric [closed]
I'm having trouble in using interpolating functions with Mathematica. Some interpolating functions I defined, say $f[x]$, if evaluated in a specific point $x_0$ correctly return the numeric value $N[f[...
- 11
3
votes
1
answer
212
views
Solve an equation
I have this equation in terms of x0 and I need to find x0 in terms of Theta .
...
- 61
2
votes
1
answer
210
views
How to get numerical value of functional derivative at specific point
I have a functional in the form:
$$F[s(x)]=\int_0^1(s(x)-a(x))^2\mathrm{d}x$$ where $a(x)$ is a parameter function, and I would like to find the functional derivative of $F$ with respect to $s$.
...
- 137
0
votes
0
answers
130
views
Can't create matrix function of symbolic functions and assign values to elements
So I have a problem regarding the symbolic matrix value assignment.
Say I create a matrix function as:
P[t_]:= {{P1[t]}, {P2[t]}, {P3[t]}};
Then I want to assign ...
1
vote
1
answer
399
views
Is there any alternative for NSolve or Solve to obtain all the roots of the given function?
I have this function for reals $0<x<\pi$.
$$f(x)=(3 \pi -2 x)^2 \sin \left(\frac{1}{2} \left(\csc ^{-1}\left(\frac{4 \pi (\pi -x) \csc \left(\frac{\pi ^2}{\pi -x}\right)}{4 x^2-8 \pi x+5 \pi ^...
- 749
1
vote
1
answer
138
views
0
votes
1
answer
77
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Is it possible to ask Mathematica to give all the roots of the given function?
I have this equation
$$ 36 \cos \frac{3 x}{4} \cos \frac{27 x}{20} \left(\cos \frac{3 x}{5} +2 \cos \frac{21 x}{10} \right)=0 $$
Is it possible to ask Mathematica to give all the roots of the ...
user67849
0
votes
0
answers
82
views
How to preserve my constants
\[Sigma] = Constant
a = Constant
b = Constant
\[Epsilon] = Constant
T[x_] := (\[Sigma]/(2*\[Epsilon]))[a/(a^2 + x^2)^(1/2) - b/(b^2 + x^2)^(1/2)]
In mathematica ...
1
vote
1
answer
115
views
The same formula performed on two different versions of Mathematica yields different results. [Life is so tough]
Let me show the code first.
...
- 173
4
votes
2
answers
2k
views
How to obtain numerical solutions of a two-variable equation?
I have a two-variable function:
f[x_, y_] := (4 y^2 - 6) (Cos[y π] Cos[x] - Cos[2 y π] Sin[x])
How can I find all the numerical solutions for $x$ and $y$ such ...
user67849
1
vote
0
answers
38
views
What is used for the % symbol in mathematica? [duplicate]
Im new in mathematica i want to know logic about this program. I got this code:
{{vo, vn, Ii}} = {vo, vn, Ii} /. %;
i know that the syntax /. is for replacement but i dont know whats going on with ...
