Measuring time of only a part of a for-loop

General Usage
1

Hi,

is there a way to the following:

for i in 1:100
	if i == 2
		@time begin
	elseif i == 88
		end
	end
end

Obviously this code does not work, but I think it makes it clear what I want to achieve: measuring the time that is needed in the loop for 2 \leq i \leq 88. Is this somehow possible? Thanks in advance!

Best regards,
Handam

2

I think GitHub - KristofferC/TimerOutputs.jl: Formatted output of timed sections in Julia should do what you’re looking for.

1 Like
3

Thanks for the quick answer!

I am still not sure what the best way is to solve my problem with the TimerOutputs package. I guess one solution would be

function instructions()
	#Some instructions
end

const to = TimerOutput()
for i in 1:100
	if i>=2 && i<= 88
		@timeit to "part_of_loop" instructions()
	else
		instructions()
	end
end

but that feels a little bit odd.
Other things I tried, which didn’t work though, were for example:

const to = TimerOutput()
disable_timer!(to)
@timeit to "part_of_loop" begin
	for i in 1:100
		if i == 2
			enable_timer!(to)
		elseif i == 88
			disable_timer!(to)
		end
		#Some instructions
	end
end

Any better solution than my first example?

4

One ugly way, but very effective, way is to triplicate your loop: copy the loop body three times and change the respective intervals to 1:1, 2:88, and 89:100; then wrap only the second loop with timing.

5

You could get your second example to work with:

const to = TimerOutput()
disable_timer!(to)
	for i in 1:100
		if i == 2
			enable_timer!(to)
		elseif i == 88
			disable_timer!(to)
		end
		@timeit to "part_of_loop" begin
                #instructions
        end
	end
end