`IPython.core.magics.execution:ExecutionMagics.time`

source: /IPython/core/magics/execution.py :1260

Signature

def time ( self , line = '' , cell = None , local_ns = None )

Summary

Time execution of a Python statement or expression.

Extended Summary

The CPU and wall clock times are printed, and the value of the expression (if any) is returned. Note that under Win32, system time is always reported as 0, since it can not be measured.

This function can be used both as a line and cell magic:

In line mode you can time a single-line statement (though multiple ones can be chained with using semicolons).
In cell mode, you can time the cell body (a directly following statement raises an error).

This function provides very basic timing functionality. Use the timeit magic for more control over the measurement.

Examples

:: In [1]: %time 2**128 CPU times: user 0.00 s, sys: 0.00 s, total: 0.00 s Wall time: 0.00 Out[1]: 340282366920938463463374607431768211456L In [2]: n = 1000000 In [3]: %time sum(range(n)) CPU times: user 1.20 s, sys: 0.05 s, total: 1.25 s Wall time: 1.37 Out[3]: 499999500000L In [4]: %time print('hello world') hello world CPU times: user 0.00 s, sys: 0.00 s, total: 0.00 s Wall time: 0.00 .. note:: The time needed by Python to compile the given expression will be reported if it is more than 0.1s. In the example below, the actual exponentiation is done by Python at compilation time, so while the expression can take a noticeable amount of time to compute, that time is purely due to the compilation:: In [5]: %time 3**9999; CPU times: user 0.00 s, sys: 0.00 s, total: 0.00 s Wall time: 0.00 s In [6]: %time 3**999999; CPU times: user 0.00 s, sys: 0.00 s, total: 0.00 s Wall time: 0.00 s Compiler : 0.78 s

Aliases

IPython.core.magics.ExecutionMagics.time