Random Numbers Selection

You can edit this FAQ section, review it or improve it!" itemscope itemtype="http://schema.org/Question">What is a random number? (Definition)

A random number is a number selected at random from an interval. The randomly selected number is usually either an integer or a decimal number.

Most often the number is calculated by computer using pseudo-randomness functions like rand() or random().

You can edit this FAQ section, review it or improve it!" itemscope itemtype="http://schema.org/Question">How to make a random number selection?

Indicate the type of numbers to draw:

— choice according to an interval: select numbers between $ a $ and $ b $

Example: Draw $ N $ digits between $ 1 $ and $ 100 $

— choice according to a size: select numbers with a certain number of digits

— choice according to a list: select numbers from a given list

Example: A phone number corresponds to N digits from 0 to 9

You can edit this FAQ section, review it or improve it!" itemscope itemtype="http://schema.org/Question">What is a random number sample without replacement?

A draw without replacement specifies that a picked number can not be picked a second time.

Example: Draws of $ 3 $ numbers between $ 1 $ and $ 5 $ could be $ 4,2,3 $ or $ 1,5,2 $ but never $ 1,2,2 $ (the $ 2 $ having been picked a first time, it is not put back into play)

During a draw without replacement, it is not possible to pick more than $ N $ numbers in a range of size $ N $

Example: A selection of $ 100 $ numbers between $ 1 $ and $ 20 $ is impossible without replacement

You can edit this FAQ section, review it or improve it!" itemscope itemtype="http://schema.org/Question">What is a random number sample with replacement?

A draw with replacement specifies that a picked number may be picked one or more times.

Example: Draws of $ 3 $ numbers between $ 1 $ and $ 5 $ could be $ 4,2,3 $ or $ 1,5,2 $ but also $ 1,2,2 $ (the $ 2 $ having been picked a first time, it is put back into play and can stand out)

During a draw with replacement, it is possible to pick more than $ N $ numbers in a range of size $ N $

Example: A selection of $ 100 $ numbers between $ 1 $ and $ 20 $ is possible with replacement

You can edit this FAQ section, review it or improve it!" itemscope itemtype="http://schema.org/Question">How to pick only even numbers?

Option 1: list the even numbers (if there are not too many) and draw from this list.

Option 2: Multiply the numbers obtained by 2, they will all be even.

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