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# cputime(-Time)

Succeeds if Time is the elapsed user cpu time in seconds.

Time
  Float number or variable.

## Description

Used to find the elapsed user cpu time in seconds, it is equivalent to statistics(times, [Time|_]).

The cpu time is the `user' time i.e. the CPU time used while executing instructions in the user space of the calling process.

Note that the granularity of the system clock is usually 1/60 or 1/50 of a second. Hence if you use cputime/1 to measure runtimes make sure that the measured intervals are long enough.

The time given by the ps command gives the sum of `user' time and `system' time, which is the CPU time used by the system on behalf of the calling process.

### Modes and Determinism

- cputime(-) is det

### Exceptions

(5) type error
  Time is instantiated, but not to a float.

## Examples

    Success:
       [eclipse]: cputime(T).
       T = 0.0333333
       yes.

    Fail:
          cputime(0.000001).
    Error:
          cputime(2).                    (Error 5).

## See Also

statistics / 0, statistics / 2, date / 1, get_flag / 2