# create a random walk function where each function value is the previous
# one plus a random change. Use this as the time changing frequency
# and make a sine wave with this frequency by numerical integration.
# sounds like the wind!
library(tuneR) # need to like with the sound library
sr = 8000 # sampling rate
bits = 16 # bit depth
secs = 10
t = seq(0,secs,1/sr)
f0 = 440
w = 1
f = rep(0,length(t))
f[1] = f0
for (i in 2:length(t)) f[i] = f[i-1] + runif(1,min=-w,max=w)
#for (i in 2:length(t)) f[i] = f0 + .995*(f[i-1]-f0) + runif(1,min=-w,max=w)
plot(f,type='l')
y = sin(cumsum(2*pi*f/sr))
u = Wave(round(2^(bits-4)*y), samp.rate = sr, bit=16) # make wave struct
play(u,"play") # play it