I need help creating a 2d array that holds a total on 49 values. 7 rows with 7 columns. in position 0,0; 1,1; 2,2; ect... the value is 0. From there 0,1 and 1,0; 0,2 and 2,0; 1,2 and 2,1; ect... are the same. Random numbers are to be inputted into the array. I'm kind of lost in how to do it. I know its using a for loop, but not sure how to write it. Help please.
Mirrored 2d Array
- Thread starter jeneal
- Start date
To iterate over a 2D array you would use nested loops:
VB.NET:
For x As Integer = 0 To myArray.GetUpperBound(0) Step 1
For y As Integer = 0 To myArray.GetUpperBound(1) Step 1
'Access myArray(x, y) here.
Next y
Next xI just read your post more carefully:
VB.NET:
For x As Integer = 0 To myArray.GetUpperBound(0) Step 1
For y As Integer = x To myArray.GetUpperBound(1) Step 1
'Access myArray(x, y) and myArray(y, x) here.
Next y
Next xNote in that second code example that y goes from x rather than from zero.
Experiment continues
Okay, this is what I have. I've added the numbers into a 2d array being assigned randomly, but giving the mirrored effect, and setting 0s as the doubles. but nothing pulls into the final text box. Anyone have any suggestions?
Okay, this is what I have. I've added the numbers into a 2d array being assigned randomly, but giving the mirrored effect, and setting 0s as the doubles. but nothing pulls into the final text box. Anyone have any suggestions?
VB.NET:
Public Class Form1
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim cities() As String = {"Canton", "Cincinnati", "Cleveland", "Columbus", "Dayton", "Toledo", "Youngstown"}
Dim city1 As String = TextBox1.Text
Dim city2 As String = TextBox2.Text
Dim cityVal As Integer
Dim xVal As Integer = 0
Dim yVal As Integer = 0
Dim mi As Integer
Dim start As Integer = 0
Dim miles(7, 7) As Integer
Dim randomGenerator As New Random
For x As Integer = start To miles.GetUpperBound(0) Step x
For y As Integer = 0 To miles.GetUpperBound(1) Step y
mi = randomGenerator.Next(1, 1000)
miles(x, y) = mi
miles(y, x) = mi
Next y
Next x
For z As Integer = 0 To z <= 6 Step z
miles(z, z) = 0
Next
cityVal = 1
While cityVal <> 0
For check1 As Integer = 0 To check1 <= 6 Step check1
cityVal = city1.CompareTo(cities(check1))
If cityVal = 0 Then
xVal = check1
check1 = 7
Else
MsgBox("Invalid City!", MsgBoxStyle.Exclamation)
End If
Next
End While
cityVal = 1
While cityVal <> 0
For check2 As Integer = 0 To check2 <= 6 Step check2
cityVal = city2.CompareTo(cities(check2))
If cityVal = 0 Then
yVal = check2
check2 = 7
Else
MsgBox("Invalid City!", MsgBoxStyle.Exclamation)
End If
Next
End While
Dim distance As Integer
distance = miles(xVal, yVal)
TextBox3.Text = distance
End Sub
End Class
Last edited by a moderator:
Place a breakpoint at the top of the code and step through it one line at a time with the F10 key. At each line you test the value of each variable to make sure that it's the value you expect, plus you can make sure that execution follows the path you expect.
At each step you need to ask yourself "what do i expect to happen next?". You then press F10 and see if what you expected to happen actually did happen. If not then you know you've found an issue. You absolutely MUST know EXACTLY what you expect to happen at each line of code. It can't possibly do what you want if you don't even know what you want.
Show us the code, tell us what you expect to happen and what actually does happen.
Show us the code, tell us what you expect to happen and what actually does happen.
code
I was asked to create a program that would take two cities put into text boxes, compair them with a declared string array.
Also a 2d array will be created and filled with random numbers. The array is a mirror of itself such that position 1,2 and 2,1 are the same, the same concept repeating through the array, where variable x = y the result of the 2darray is 0.
The program loops through and checks if the city is vaild and stores it position in the array such that city1 = x and city2 = y. If the city is not found in the array an error box is displayed. When both cities are valid, a random number shows up in the third text box.
Theoretically since the array is mirrored, it shouldn't matter the city order the output should be the same between say cleveland and canton compaired to canton and cleveland. If the cities are the same then the result is zero.
For reasons that I can't explain random numbers apper in the outbox but the above conditions do not happen. I've tried many diffrent ways of writing the code, but here is my latest version. If someone can look at it and point me into the right direction I would appreciate it.
I was asked to create a program that would take two cities put into text boxes, compair them with a declared string array.
Also a 2d array will be created and filled with random numbers. The array is a mirror of itself such that position 1,2 and 2,1 are the same, the same concept repeating through the array, where variable x = y the result of the 2darray is 0.
The program loops through and checks if the city is vaild and stores it position in the array such that city1 = x and city2 = y. If the city is not found in the array an error box is displayed. When both cities are valid, a random number shows up in the third text box.
Theoretically since the array is mirrored, it shouldn't matter the city order the output should be the same between say cleveland and canton compaired to canton and cleveland. If the cities are the same then the result is zero.
For reasons that I can't explain random numbers apper in the outbox but the above conditions do not happen. I've tried many diffrent ways of writing the code, but here is my latest version. If someone can look at it and point me into the right direction I would appreciate it.
VB.NET:
Public Class Form1
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim cities() As String = {"Canton", "Cincinnati", "Cleveland", "Columbus", "Dayton", "Toledo", "Youngstown"}
Dim city1 As String = TextBox1.Text
Dim city2 As String = TextBox2.Text
Dim cityVal As Integer = 0
Dim xVal As Integer = 0
Dim yVal As Integer = 0
Dim mi As Integer
Dim miles(7, 7) As Integer
Dim randomGenerator As New Random
While cityVal <= 6
For check1 As Integer = 0 To check1 <= 6
cityVal = city1.CompareTo(cities(check1))
If cityVal <= 6 Then
xVal = check1
check1 = 7
For check2 As Integer = 0 To check2 <= 6
cityVal = city2.CompareTo(cities(check2))
If cityVal <= 6 Then
yVal = check2
check2 = 7
Else
MsgBox("Invalid City!", MsgBoxStyle.Exclamation)
End If
Next check2
Else
MsgBox("Invalid City!", MsgBoxStyle.Exclamation)
End If
Next check1
cityVal = 7
End While
For x As Integer = 0 To 6
For y As Integer = 0 To 6
If x = y Then
miles(x, y) = 0
End If
mi = randomGenerator.Next(1, 1000)
miles(x, y) = mi
miles(y, x) = miles(x, y)
Next
Next
Dim distance As Integer
distance = miles(xVal, yVal)
TextBox3.Text = distance
End Sub
End Class
Last edited by a moderator:
