VERSION 5.00
Begin VB.Form FrmGridExtent 
   Caption         =   "Output Grid Extent"
   ClientHeight    =   2820
   ClientLeft      =   60
   ClientTop       =   345
   ClientWidth     =   5835
   LinkTopic       =   "Form1"
   ScaleHeight     =   2820
   ScaleWidth      =   5835
   StartUpPosition =   2  'CenterScreen
   Begin VB.TextBox TxtMaxY 
      Height          =   285
      Left            =   3960
      TabIndex        =   9
      Text            =   "5426200"
      Top             =   1440
      Width           =   1215
   End
   Begin VB.TextBox TxtMinY 
      Height          =   285
      Left            =   1440
      TabIndex        =   8
      Text            =   "5424000"
      Top             =   1440
      Width           =   1215
   End
   Begin VB.TextBox TxtMaxX 
      Height          =   285
      Left            =   3960
      TabIndex        =   7
      Text            =   "559400"
      Top             =   960
      Width           =   1215
   End
   Begin VB.TextBox TxtMinX 
      Height          =   285
      Left            =   1440
      TabIndex        =   6
      Text            =   "557000"
      Top             =   960
      Width           =   1215
   End
   Begin VB.CommandButton CmdCalcBB 
      Caption         =   "Calculate Browninan Bridge Grid"
      Height          =   375
      Left            =   1440
      TabIndex        =   1
      Top             =   2160
      Width           =   3255
   End
   Begin VB.CommandButton CmdCalcGridExtent 
      Caption         =   "Auto Calculate Grid Extent"
      Height          =   375
      Left            =   2040
      TabIndex        =   0
      Top             =   360
      Width           =   2295
   End
   Begin VB.Label Label4 
      Caption         =   "Maximum Y"
      Height          =   255
      Left            =   3000
      TabIndex        =   5
      Top             =   1440
      Width           =   975
   End
   Begin VB.Label Label3 
      Caption         =   "Minimum Y"
      Height          =   255
      Left            =   480
      TabIndex        =   4
      Top             =   1440
      Width           =   975
   End
   Begin VB.Label Label2 
      Caption         =   "Maximum X"
      Height          =   255
      Left            =   3000
      TabIndex        =   3
      Top             =   960
      Width           =   975
   End
   Begin VB.Label Label1 
      Caption         =   "Minimum X"
      Height          =   255
      Left            =   480
      TabIndex        =   2
      Top             =   960
      Width           =   975
   End
End
Attribute VB_Name = "FrmGridExtent"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = False
Private Sub CmdCalcGridExtent_Click()

Dim CurrentX As Single
Dim CurrentY As Single
Dim XMax As Single
Dim Xmin As Single
Dim YMax As Single
Dim YMin As Single
Dim I As Long

XMax = SortedXYArray(0, 0)
Xmin = SortedXYArray(0, 0)
YMax = SortedXYArray(0, 1)
YMin = SortedXYArray(0, 1)

For I = 1 To NumOfLocs - 1
    If SortedXYArray(I, 0) > XMax Then
        XMax = SortedXYArray(I, 0)
    End If
    If SortedXYArray(I, 0) < Xmin Then
        Xmin = SortedXYArray(I, 0)
    End If
    If SortedXYArray(I, 1) > YMax Then
        YMax = SortedXYArray(I, 1)
    End If
    If SortedXYArray(I, 1) < YMin Then
        YMin = SortedXYArray(I, 1)
    End If
Next

LowerLeftX = Xmin - (XMax - Xmin) / 2
LowerLeftY = YMin - (YMax - YMin) / 2
UpperRightX = XMax + (XMax - Xmin) / 2
UpperRightY = YMax + (YMax - YMin) / 2

TxtMinX.Text = LowerLeftX
TxtMaxX.Text = UpperRightX
TxtMinY.Text = LowerLeftY
TxtMaxY.Text = UpperRightY

End Sub

Private Sub CmdCalcBB_Click()

LowerLeftX = TxtMinX.Text
UpperRightX = TxtMaxX.Text
LowerLeftY = TxtMinY.Text
UpperRightY = TxtMaxY.Text

Dim XGridStep As Single
Dim YGridStep As Single
Dim GridNum As Long

XGridStep = (UpperRightX - LowerLeftX) / 249
YGridStep = (UpperRightY - LowerLeftY) / 249

CurrentX = LowerLeftX
CurrentY = LowerLeftY

Dim StartX As Single
Dim StartY As Single
Dim EndX As Single
Dim EndY As Single
Dim StartTime As Double
Dim EndTime As Double
'Dim BBVar As Single

Dim EntireTime As Single
Dim TotalTime As Single
Dim TimeT As Single
Dim Alpha As Single
Dim TimeStep As Single
Dim MeanXTimeT As Single
Dim MeanYTimeT As Single
Dim VarTimeT As Single
Dim ProbAtTimeT As Double
Dim SqDistance As Single
Dim SumProbAcrossTime As Double
Dim BBProbDensityAtGridPoint As Double
Dim SumBBProbDensityAtGridPoint As Double
ReDim BBProbGridArray(100000, 3) As Single

'EntireTime = SortedXYArray(NumOfLocs - 1, 2) - SortedXYArray(0, 2)

I = 0
If TelemErrorStdDev = 0 Then
    TelemErrorStdDev = 0.0001
End If

Do Until CurrentX > UpperRightX
    Do Until CurrentY > UpperRightY
        'Calculate Brownian Bridge Probability at grid point
        SumBBProbDensityAtGridPoint = 0
        EntireTime = 0
        For LocNum = 0 To NumOfLocs - 2
            StartX = SortedXYArray(LocNum, 0)
            StartY = SortedXYArray(LocNum, 1)
            StartTime = SortedXYArray(LocNum, 2)
            EndX = SortedXYArray(LocNum + 1, 0)
            EndY = SortedXYArray(LocNum + 1, 1)
            EndTime = SortedXYArray(LocNum + 1, 2)
            TotalTime = EndTime - StartTime
            TimeStep = TotalTime / 100
            TimeT = 0
            SumProbAcrossTime = 0
        If TotalTime > TotalTimeTooLong Then
            Else
                Do Until TimeT > TotalTime
                
                Alpha = TimeT / TotalTime
                MeanXTimeT = StartX + ((Alpha) * (EndX - StartX))
                MeanYTimeT = StartY + ((Alpha) * (EndY - StartY))
                    VarTimeT = TotalTime * Alpha * (1 - Alpha) * BBVariance + (Alpha ^ 2 + (1 - Alpha) ^ 2) * TelemErrorStdDev ^ 2
                SqDistance = (CurrentX - MeanXTimeT) ^ 2 + (CurrentY - MeanYTimeT) ^ 2
                ProbAtTimeT = (1 / (2 * Pi * VarTimeT)) * Exp(-0.5 * (SqDistance / VarTimeT)) * TimeStep
                SumProbAcrossTime = SumProbAcrossTime + ProbAtTimeT
                TimeT = TimeT + TimeStep
                
            Loop
            EntireTime = EntireTime + TotalTime
            BBProbDensityAtGridPoint = SumProbAcrossTime
            SumBBProbDensityAtGridPoint = SumBBProbDensityAtGridPoint + BBProbDensityAtGridPoint
            If UseAllLocs = False Then
                LocNum = LocNum + 1
            End If
        End If
        Next LocNum
        BBProbGridArray(I, 0) = CurrentX
        BBProbGridArray(I, 1) = CurrentY

        If UseAllLocs = False Then
            BBProbGridArray(I, 2) = (SumBBProbDensityAtGridPoint / (EntireTime)) * (XGridStep * YGridStep)
        Else
            BBProbGridArray(I, 2) = (SumBBProbDensityAtGridPoint / (NumOfLocs - 1)) * (XGridStep * YGridStep)
            BBProbGridArray(I, 2) = (SumBBProbDensityAtGridPoint / (EntireTime)) * (XGridStep * YGridStep)
        End If
        I = I + 1
        CurrentY = CurrentY + YGridStep
        GridNum = GridNum + 1
    Loop
CurrentY = LowerLeftY
CurrentX = CurrentX + XGridStep
Loop
GridDimension = I
SaveFileType = "BBGrid"
Call Unload(FrmGridExtent)
FrmSaveAsBrownBridge.Show
End Sub