graphics - Graphing the amount of time a function takes

I know I can find out the amount of time a function takes to run like this:

In:=  function1[100] //Timing
Out:= {0.043334, Null}

How can I graph this over a set of 10 or 20 parameters (which are increasingly large), in order to get an idea of how the function scales?

Answer

This isn't the most exciting example but I hope it helps.

Use AbsoluteTiming to time the function and use Table to iterate over a set of values. We're simply going to time the Pause function which just waits x seconds, in this case x^2. The values will be stored as list. First gives us the first element of the output of AbsoluteTiming which is the time taken.

list = Table[First[AbsoluteTiming[Pause[x^2]]], {x, 0, 0.1, 0.01}];

Then we'll plot it with ListPlot

ListPlot[list]

Mathematica graphic

Comments

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