Extract Trough and Peak Dates in xts object

x = as.xts(1:30,Sys.Date()+1:30) 

# extract smallest value date
( time.trough <- time(x)[ x == min(x) ] )

# extract largest value date

( time.peak <- time(x)[ x == max(x) ] )

# extract particular value date

( time.one <- time(x)[ x == 1 ] )