•time — Timing

•time t gives the seconds since the moment t. Moments count seconds from the Unix epoch, as •date reads and writes them. •time 0 is the current moment. t←•time 0 starts a timer, and •time t then gives the seconds since it started.

F •time x calls each function in F on x for about 0.1 s. The result is each function’s fastest time per call in seconds, with the shape and keys of F. With F←["sum":+/ "max":⌈/], F •time x labels each time. Put a single function in brackets, as in [f] •time x. A function before •time takes the result of •time x as its argument, so f •time x times nothing. Time a dyadic function with its left argument bound, as in 2↣⍴. Timing has examples.

Errors: DOMAIN for a left argument that holds anything but functions, or a t that isn’t a number. An error from a timed function stops the timing.