etime input arguments, what do they mean?

Hi

I am using etime for a piece of code:

start=clock
limit=10
while etime(clock,start) < limit
    rotate(xxxx)
end

I am rotating something. My question is though, seeing as we have start=clock i.e. they are equivalent, I am assuming elapsed time is 0, and that while elapsed time = 0 < limit, the rotation will take place?

Have I understood this correctly?

Thanks.

Answer 1

[Jan]

Take a look into the documentation:

doc clock
doc etime

Then run some own tests: type this in the command window:

clock
% wait a little bit
clock

You see, clock replies the current time and date as a [1 x 6] vector.

According to the help text, etime replies the number of seconds between two date/time vectors.

The line "start=clock" stores the output of the function clock in the variable start. Comparing the output of the next call of clock with the value of start replies the elapsed time.

In the shown code this means, that the loop runs, until 10 seconds have past.

See this online tutorial to learn the basics: https://www.mathworks.com/learn/tutorials/matlab-onramp.html