I have a density object dd created like this:
x1 <- rnorm(1000)
x2 <- rnorm(1000, 3, 2)
x <- rbind(x1, x2)
dd <- density(x)
plot(dd)
Which produces this very non-Gaussian distribution:
alt text http://www.cerebralmastication.com/wp-content/uploads/2009/09/nongaus.png
I would ultimately like to get random deviates from this distribution similar to how rnorm gets deviates from a normal distribution.
The way I am trying to crack this is to get the CDF of my kernel and then get it to tell me the variate if I pass it a cumulative probability (inverse CDF). That way I can turn a vector of uniform random variates into draws from the density.
It seems like what I am trying to do should be something basic that others have done before me. Is there a simple way or a simple function to do this? I hate reinventing the wheel.
FWIW I found this R Help article but I can't grok what they are doing and the final output does not seem to produce what I am after. But it could be a step along the way that I just don't understand.
I've considered just going with a Johnson distribution from the suppdists package but Johnson won't give me the nice bimodal hump which my data has.
Alternative approach:
sample(x, n, replace = TRUE)
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