A Discrete distribution is used to specify a discrete (as opposed to continuous) probability density function. In a Discrete distribution, probabilities are assigned to discrete values. The probability of a value between the specified values is zero.
You define the distribution by specifying [probability, value] pairs. A given pair (defined by a Probability and a Value) implies that the probability of the Value is equal to the specified Probability:
In this example, the probability of the value being equal to 3 is 50%.
You add and remove pairs using the Add and Remove buttons (new pairs are inserted below the selected pair). In addition, if you place the cursor in the grid, the following hotkeys can be used:
|
Keys |
Action |
|
Ctrl+Enter |
creates a new row below the cursor |
|
Ctrl+Shift+Enter |
creates a new row above the cursor |
|
Ctrl+Backspace |
deletes the current row |
By definition, the probabilities must sum to one. The Values do not need to be in any particular order (GoldSim will automatically sort them in increasing order when the data is applied). However, if the Probabilities do not sum to one, GoldSim will warn you and ask you to fix the distribution.
Note: The
values and probabilities must be entered as numbers and cannot be specified
using links or expressions. The values are assumed to be entered in the Display
Units for the element (which are displayed in the header for the editing
grid).
Note: You can
copy and paste the entries for a Discrete distribution from a spreadsheet. To do
so, select the two columns in the spreadsheet (Probability and Value), and copy
them to the clipboard. Then place the cursor in the upper left-hand corner of
the grid (i.e., the first Probability) and paste (by pressing
Ctrl+V).
Note: Since this is a discrete distribution, the PDF view does not
actually display a probability density
function. Instead, it displays a probability
mass function.