Random number range?

[Doolittle 0]

Anyone have an algorithm that will take low, mid, and high numbers and give me back a random number? Just like the Triggers use where they have a low number and a high one and a "median". Like low of 1, high of 10 and mid of 8 would mean you're most likely to get on or near 8. Anyone know what I'm talking about? I need to simulate this in a script, not from a trigger. I.e. I wish to expand upon the random command.

Thanks!

Doolittle

[Doolittle 0]

This is what I got so far:

<table border="0" align="center" width="95%" cellpadding="0" cellspacing="0"><tr><td>Code Sample </td></tr><tr><td id="CODE">

randrange = {

_min = _this select 0;

_max = _this select 1;

_calcmin = _this select 2;

_calcmax = _this select 3;

if (_calcmin < _min) then {_calcmin = _min};

if (_calcmax > _max) then {_calcmax = _max};

_calcmin + random (_calcmax - _calcmin);

};

_sum = 0;

for [{_i = 1}, {_i <= (_mid - _min)}, {_i = _i + 1}] do {

_sum = _sum + [_min, _max, _mid - _i, _mid + _i] call randrange;

};

_sum / (_mid - _min); // return value

So...

_min = 1

_mid = 7

_max = 8

Get rand between 6 and 8

Get rand between 5 and 8

Get rand between 4 and 8

Get rand between 3 and 8

Get rand between 2 and 8

Get rand between 1 and 8

Add up & take average

Does this look right?

[norrin 9]

You could try this (untested):

<table border="0" align="center" width="95%" cellpadding="0" cellspacing="0"><tr><td>Code Sample </td></tr><tr><td id="CODE">//To calculate a random number (_random_no) between two boundaries

_min = _this select 0;

_max = _this select 1;

_range = _max - _min;

_value = ciel(random _range);

_random_no = _min + _value;

if (true) exitWith {};

EDIT: Oops I missed the mid part. Will think about this more.

[Doolittle 0]

Thanks! But I need it to have a mid point... if that makes since?

Like range of 15 to 40 with mid of 35.

This helped a little: http://www.adit.co.uk/html/random_numbers.html

Talks about a weighted value and stuff. Sigh. I used to know this stuff. Now it looks like alien writing.

Doolittle

EDIT:

http://en.wikipedia.org/wiki/Probability_distribution

http://www.gamedev.net/community/forums/topic.asp?topic_id=267560

[norrin 9]

Thanks! But I need it to have a mid point... if that makes since?

Like range of 15 to 40 with mid of 35.

This helped a little: http://www.adit.co.uk/html/random_numbers.html

Talks about a weighted value and stuff. Sigh. I used to know this stuff. Now it looks like alien writing.

Doolittle

OK take 2

Once again untested.

*Other than the _low, _mid and _high values you'll need to specify the probability that the value is going to be near the mid point (needs to be a number between 0 and 1).

*You'll also need to specify the range that the number falls within if its near the mid point. (eg. 2 below or 2 above mid would give a _range_mid = 4)

<table border="0" align="center" width="95%" cellpadding="0" cellspacing="0"><tr><td>Code Sample </td></tr><tr><td id="CODE">

_min = _this select 0;

_mid = _this select 1;

_high = _this select 2;

_range_mid = _this select 3;

_probability_of_mid = _this select 4;

_range_all = _high - _min;

_chosen_range = random 1;

if (_chosen_range <= _probability_of_mid) then

{

_value = ciel(random _range_mid);

if (_value <= _range_mid/2) then {_random_no = _mid - _value} else {_random_no = _mid + _value};

} else

{

_value = ciel(random _range_all);

_random_no = _min + _value;

};

if (true) exitWith {};

The only prob with this is there's still a possibility that the value will be near the mid point even if _chosen_range > _probability_of_mid but its going to be slim.

[norrin 9]

Sorry to double post but I've looked through your stats and the median is the same as the 2nd quartile and therefore cuts the data in half ( http://en.wikipedia.org/wiki/Quartile ). Therefore 50% of the data will be below the median value and 50% above this value.

If this is true then something like this should work: <table border="0" align="center" width="95%" cellpadding="0" cellspacing="0"><tr><td>Code Sample </td></tr><tr><td id="CODE">_min = _this select 0;

_median = _this select 1;

_high = _this select 2;

_range_low = _median - _min;

_range_high = _high - _median;

_probability = random 1;

if (_probabilty <= 0.5) then

{

_value = random _range_low;

_random_no = _min + _value;

}else

{

_value = random _range_high;

_random_no = _mid + _value;

};

if (true) exitWith {};

[Doolittle 0]

Never heard the word quartile before.. hah.

I think this is what I will do... randrange returns a random between two numbers.

<table border="0" align="center" width="95%" cellpadding="0" cellspacing="0"><tr><td>Code Sample </td></tr><tr><td id="CODE">[[_min, _mid] call randrange, [_mid, _max] call randrange] call randrange