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1d
comment Convex optimization with groups
Many thanks for all the inputs. I need to implement this in java, so I guess I'll end up using something like jOptimizer. But thanks for the references anyway :)
2d
comment Convex optimization with groups
@JohanLöfberg Ok, I get it. Thanks a lot. Do you know whether one can conclude the existence of solutions already from this form?
2d
comment Convex optimization with groups
Could you elaborate on the notation? The way I regard it, x and y are statically linked (see equality constraint). Therefore I should only be optimizing for one variable, right? After all, I want to optimize the utility for the aggregate resources assigned to each user, and which resources are demanded by what user is preliminarily known.
2d
asked Convex optimization with groups
Dec
7
comment Find the fixed points
Thank you @Adam, I've added the case $b=0$ to the solution.
Dec
7
revised Find the fixed points
added 119 characters in body
Jul
30
awarded  Commentator
Jul
30
comment Modified balls and bins
What have you tried so far?
Jul
30
comment Represent code in math notation
What is the purpose of this?
Jun
20
comment Roulette probability
If your probability for winning is $p$, the probability for losing is $q = 1-p$. Independent random events(such as your roulette example or throwing a dice), allow you to multiply the probabilities.$$$$ E.g. scoring 6 twice in a row with a dice has a probability of one out of six, times one out of six: $\frac{1}{6}*\frac{1}{6}=\frac{1}{36}$.
Jun
19
answered What does ($\ln x$) or ($\log x$) mean?
Jun
18
answered Probability, combinations with repetition
Jun
18
comment Probability, combinations with repetition
Don't you have any information on the respective quantities of the different fruits?$$$$
Jun
18
comment How to write two for loops in math notation?
$$(1+2+3+4+5)^2$$
Jun
18
comment state space model
Basically, your fist equation is your system model, i.e. how you expect your system to move on to step 11 given step 10. $n(t)$ denotes the modeling error, e.g. errors due to numerical calculations.$$$$ The second equation describes your system observation i.e. the output of your sensors and can be anything from velocity to torque or position. The error term $v(t)$ denotes the measurement error which stems from non ideal sensors.
Jun
18
comment Solve $x^x=2x$ where $x\in\mathbb C$.
I can show you how I started: The Lambert W function is given as $z=W(z)*e^{W(z)}$. What you are trying to obtain is a expression on x which matches this function. You can start with $x^x=2x$ using the logarithm you obtain $x\ln{x}=\ln{2x}=\ln{2}+\ln{x}$. Then: $$x\ln{x}-\ln{x}=\ln{2}$$ $$(x-1)\ln{x}=\ln{2}$$ $$e^{\ln{x-1}}\ln{x}=\ln{2}$$ Now we almost arrived at the desired form. However, $x-1$ is still causing troubles...
Jun
18
answered Choosing balls out of a bag, replacing them by opposite colour
Jun
15
revised Find the fixed points
added
Jun
15
answered Find the fixed points
Jun
15
revised Find the fixed points
correction, fraction was $\frac{1-a}{b}$