How do a perform a weighted, 2d kernel density estimation in R?

I would like to produce a kernel density estimation in R, and am somewhat bamboozled by all the different packages. I need to be able to:

1. Specify weights
2. Specify bandwidth size
3. Specify bin size

How would you go about this? Bonus points for a code snippet开发者_运维技巧.

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See also the ks package and the nice picture in Multivariate kernel density estimation.

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Off course there's a number of packages. You should first decide which 2D kernel estimate you want. In the fields package you have a function smooth.2d, and you have the wonderful package of Brian Ripley, KernSmooth. The extra points for the code snippets you can give to the help files, I ain't going to copy them.

For these kind of questions, also try www.rseek.org.