;+ ; NAME: montecarlo_mean ; PURPOSE: ; given a set of numbers, uses monte-carlo methods to determine ; both the mean and the standard deviation of the mean. ; ; INPUTS: ; data a set of data ; KEYWORDS: ; ntrials number of monte carlo trials [default = 100] ; OUTPUTS: ; mean mean of the data ; medstddev stddev of the mean ; ; HISTORY: ; Began 2002-08-16 15:17:37 by Marshall Perrin ;- PRO montecarlo_mean,data,mmean,medstddev,ntrials=ntrials,silent=silent if not(keyword_set(ntrials)) then ntrials = 100 mmean = mean(data) meds = fltarr(ntrials) if not(keyword_set(silent)) then message,/info,"Calculating mean & stddev" for n=0,ntrials-1 do begin indices = floor(randomu(seed,n_elements(data))*n_elements(data)) meds[n] = mean(data[indices]) endfor if not(keyword_set(silent))then print,mmean, stddev(meds) medstddev = stddev(meds) end