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Example 1a: Simulate a single toss of a fair coin.
Example 1b: Simulate a single toss of a coin with probability p of heads.
Example 1c: Simulate a single spin of a roulette wheel.
Problem 1: Simulate the throw of a fair die.
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Object, Property and settings:
Object Property Setting
Form Name frmCoinTossFair
Caption Simple Coin Toss Label
Label Name Label1
Caption Outcome:
Alignment 1-Right Justify Label
Label Name lblOutput
Caption (Blank)
CommandButton Name cmdToss
Caption &Toss Coin
CommandButton Name cmdQuit
Caption &Quit
Event Procedures:
' In (Declarations) section of (General)
' Project Name: Single Toss of a Fair Coin
' Date: May, 1996
' Programmer: R. Berman
' Description: This program simulates a single toss
' of a fair coin and outputs the result.
' Require explicit declaration of variables used in this module.
Option Explicit
Sub cmdToss_Click ()
Randomize Timer ' Seed random number generator with present time
' RND returns a random number, 0 <= RND < 1
If RND < .5 Then ' RND < .5 corresponds to heads "H"
lblOutput.Caption = "H" ' Display "H" in lblOutput
Else ' Rnd >= .5 corresponds to tails "T"
lblOutput.Caption = "T" ' Display "T" in lblOutput
End If
End
Sub cmdQuit_Click ()
End ' End the application
End Sub
Object, Property and settings:
Object Property Setting Form Name frmCoinTossGeneral Caption Simple Toss of a Coin Label Name Label1 Caption Input the probability of heads: Alignment 1-Right Justify Text Name txtProb Text .5 Label Name Label2 Caption Outcome: Alignment 1-Right Justify Label Name lblOutput Caption (Blank) CommandButton Name cmdToss Caption &Toss Coin CommandButton Name cmdQuit Caption &Quit
Event Procedures:
' In (Declarations) section of (General)
' Project Name: Single Toss of a Coin
' Date: May, 1996
' Programmer: R. Berman
' Description: This program simulates a single toss of a coin with
' probability input by the user.
' Require explicit declaration of variables used in this module.
Option Explicit
Sub cmdToss_Click ()
Dim s_Prob As Single ' Declare the variable for the user input of
' of the probability. The "s" is a convention
' to remind the programmer that the variable is
' "Single" data type.
s_Prob = Val(txtProb.Text) ' Set s_Prob to the numerical value in txtProb.Text
Randomize Timer ' Seed random number generator with present time
' RND returns a random number, 0 <= RND < 1
If RND < s_Prob Then ' RND < s_Prob corresponds to heads
lblOutput.Caption = "H" ' Display "H" in lblOutput
Else ' Rnd >= p corresponds to tails
lblOutput.Caption = "T" ' Display "T" in lblOutput
End If
End Sub
Sub cmdQuit_Click () is the same as before.
Object, Property and settings:
Object Property Setting Form Name frmRoulette Caption Spin of a Roulette Wheel: Label Name Label1 Caption The number on the roulette wheel Alignment 1-Right Justify Label Name lblOutput Caption (Blank) CommandButton Name cmdSpin Caption &Spin Wheel CommandButton Name cmdQuit Caption &Quit
Event Procedures:
' In (Declarations) section of (General)
' Project Name: Single Spin of a Roulette Wheel
' Date: May, 1996
' Programmer: R. Berman
' Description: Smulates a single spin of the roulette wheel
' Require explicit declaration of variables used in this module.
Option Explicit
Sub cmdSpin_Click ()
Dim i_Outcome as Integer ' Declare the integer variable i_Outcome
Randomize Timer ' Seed random number generator with present time
i_Outcome = Int(38 * Rnd) - 1 ' Rnd returns a random number, 0 <= Rnd < 1
' Int(x) returns the largest integer <= x
' Therefore, i_Outcome is a random integer, -1 <= i_Outcome < 38
IF i_Outcome <> -1 THEN ' In case i_Outcome >=0 display its value as the outcome
lblOutcome.Caption = Str$(i_Outcome)
Else ' In case i_Outcome = -1 display "00"
lblOutcome.Caption = "00"
End If
End Sub
Sub cmdQuit_Click () is the same as before.
