How fast does & perform?
- To: mathgroup at smc.vnet.net
- Subject: [mg107293] How fast does & perform?
- From: Canopus56 <canopus56 at yahoo.com>
- Date: Mon, 8 Feb 2010 03:35:33 -0500 (EST)
Setting aside the syntax question of the thread "What does & mean?", there appears to be a performance difference between the two syntax forms. Looks like the := form is faster:
data = Table[x, {x, (\[Pi]/8), \[Pi], (\[Pi]/512)}]
g[x_] := x*Sin[x]
Timing[Table[g[data[[k]]], {k, 1, Length[data]}]]
2.71051*10^-17 seconds
Timing[Map[g, data]]
0. seconds
Timing[Map[g[#] &, data]]
0.016 seconds
Timing[Map[#*Sin[#] &, data]]
0.031 seconds
Timing[#*Sin[#] & /@ data]
0.032 seconds
- Kurt