Running an equation a million times

[andyg55]

Hi guys,

I'm sure this is pretty simple really, but I can't get my head around it.

I have a long equation that I'm using c++ to work out. It involves a random number generator, so each time the program is run, it replaces one of the variables in the equation with a random number. This gives me a different result each time :)

What I want to do is run the program a million times, store every result that I obtain, and then get an average at the end.

I'm thinking I should put a for loop at the start of my equation, but do I use a counter to record every result I get? I'm really not sure.

Thanks for any help you can give me, if you would like me to post some code I can do...

Andy.

[andyg55]

ok, instead i did a while loop like this:

while(repeats != 1000000){
Equation = x + y;
Cout << Equation;
repeats++;
}

So basically, it prints the above 1000000 times. Instead, what I want it to do is record every value of x, add them all up, and then divide by 1000000 to get an average. I then want this to be displayed to screen.

Any ideas?

[DevonMcC++]

Try summing the results of the equation - printing out a million things is absolutely useless - then dividing by 1e6 at the end of the loop. Better yet, use an array-based language to avoid finding a problem where there isn't any.

ok, instead i did a while loop like this:

while(repeats != 1000000){
Equation = x + y;
Cout << Equation;
repeats++;
}

So basically, it prints the above 1000000 times. Instead, what I want it to do is record every value of x, add them all up, and then divide by 1000000 to get an average. I then want this to be displayed to screen.

Any ideas?

[xylog]

I would use a running average and only store the last value and average value in memory. Storing millions of values will just waste memory and slow you down.