rnd()

[y offs et]

As I read it "rnd() - returns a random number in the range 0 to 1. "
means -
integers 0 and 1 are possible, as well as fractions between
correct?

[VilleK]

The rnd()-function use the built-in Random-function in Delphi which behaves just like the corresponding function in most programming languages. It returns values in the range: 0 <= Number < 1.0

So it can be zero and 0.99999 but never 1.0. If you type: "int x=rnd() * 5;" you will get values between 0 and 4.

http://www.delphibasics.co.uk/RTL.asp?Name=Random

[y offs et]

Thanks for link. I've overviewed at least a dozen languages and there is always little differences. I'll clarify the Docs.

"int x=rnd() * 5;"
Small question - if x is already defined as an integer variable, is the "int" required? I've been using x = round(rnd()*5);

[jph_wacheski]

So

"int x=rnd() * 5;" you will get values between 0 and 4.9995

correct?

[VilleK]

You don't have to redeclare x if it is already defined so "x=" is enough.

float f=rnd() * 5; //Gives a number between 0 and 4.99999...

int x=round(rnd() * 5); //Gives an integer between 0 and 5

int x=rnd() * 5; //Gives an integer between 0 and 4

Round() rounds values to the nearest integer, so 4.6 rounds up to 5. The default number to integer conversion is to truncate the decimals so that 4.7894 becomes 4.

I'm writing from memory and I haven't verified the information above in the editor, but this is how it should work

[y offs et]

according to the link -

" round(x) - returns the integer part of x " from the Docs is incorrect.

trunc() is the function that produces this

http://www.delphibasics.co.uk/RTL.asp?Name=Trunc

----------------

On checking others, I see you have been inventing some. Hmm...

[VilleK]

If you find inconsistencies between the wiki and the Delphi-docs then the Delphi-docs are probably more correct.

[y offs et]

OK. So that means there is no actual truncation function and I'll have to find another way.

[VilleK]

Trunc is basically x-frac(x).