VBA,Beams Design , Structural API functions.

Public Function kg_superposition_moment_value(dist As Double, W As Double, L As Double, Optional P1 As Double, Optional D1 As Double, Optional P2 As Double, Optional D2 As Double, Optional Mnegtv1 As Double, Optional Mnegtv2 As Double)
    Dim Mcalculated, MPosValue, MNegValue As Double
    MPosValue = 0
    MNegValue = 0
    If dist > L Then
        kg_superposition_moment_value = "Dist Exceed L"
        Exit Function
    End If
    '' -- Calculate Negative Moment Value
    ''1 - ONE NEGATIVE
    If Mnegtv2 <> 0 And Mnegtv1 = 0 Then
        ' Case 1
        MNegValue = (Mnegtv2 * dist) / L
    ElseIf Mnegtv1 <> 0 And Mnegtv2 = 0 Then
        ' Case 2
        MNegValue = (Mnegtv1 * (L - dist)) / L
    Else
        ''TWO ARE ZERO OR TWO AREN'T ZERO
        If Mnegtv2 <> 0 And Mnegtv1 <> 0 Then
            If (Mnegtv2 > Mnegtv1) Then
            'CASE 3
                MNegValue = Mnegtv1 + (((Mnegtv2 - Mnegtv1) * (dist)) / L)
            Else
            'CASE 4
               MNegValue = Mnegtv2 + (((Mnegtv1 - Mnegtv2) * (L - dist)) / L)
            End If
        End If
    End If
    '' -- Calculate Postive Moment Value
    'Parabola Moment
    Mcalculated = (W * L * L) / 8
    MPosValue = (((-Mcalculated) / ((L / 2) * (L / 2))) * ((dist - L / 2) * (dist - L / 2))) + Mcalculated
    'P1 Moment
    If (P1 <> 0) Then
        Mcalculated = P1 * D1 * (L - D1) / L
        If (dist <= D1) Then
        'Point Locate Before vertex
            MPosValue = MPosValue + ((Mcalculated * dist) / D1)
        Else
        'Point Locate After Vertex
          MPosValue = MPosValue + (Mcalculated * (L - dist)) / (L - D1)
        End If
    End If
    'P2 Moment
    If (P2 <> 0) Then
        Mcalculated = P2 * D2 * (L - D2) / L
        If (dist <= D2) Then
        'Point Locate Before vertex
            MPosValue = MPosValue + ((Mcalculated * dist) / D2)
        Else
        'Point Locate After Vertex
          MPosValue = MPosValue + (Mcalculated * (L - dist)) / (L - D2)
        End If
    End If

    kg_superposition_moment_value = MNegValue + MPosValue
End Function


Public Function Kg_get_span_case(W As Double, L As Double, P1 As Double, D1 As Double, P2 As Double, D2 As Double)
  ' CASES
  ' 1 => Ws With NO Concentrated Loads
  ' 2 => Ws With One Concentrated
  ' 3 => Ws With Two Loads [D1 & D2 Before Mid-Span]
  ' 4 => Ws With Two Loads [One Load is at mid-span]
  ' 5 => Ws With Two Loads [One Before & One after mid-span]

  If (W = 0) Then
    Kg_get_span_case = 0
        Exit Function
  End If

  If P1 = 0 And P2 = 0 Then
  'No Concentrated Loads Exist[Case 1]
    Kg_get_span_case = 1
  ElseIf P1 = 0 Or P2 = 0 Then
  'One Exist [Case 2]
    Kg_get_span_case = 2
  Else
  'Two Loads Exist [3,4,5]
    If (D1 < L / 2 And D2 < L / 2) Or (D1 > L / 2 And D2 > L / 2) Then
        Kg_get_span_case = 3
    ElseIf (D1 <> 0 And D2 = L / 2) Or (D2 <> 0 And D1 = L / 2) Then
        Kg_get_span_case = 4
    ElseIf (D1 > L / 2 And D2 < L / 2) Or (D2 > L / 2 And D1 < L / 2) Then
        Kg_get_span_case = 5
    Else
        MsgBox "Unexpected ERR"
    End If
  End If

End Function


Public Function Kg_get_station_coordinate(Sindex As Integer, BasePoint As Double, W As Double, L As Double, P1 As Double, D1 As Double, P2 As Double, D2 As Double)
Dim X As Double

Select Case Sindex
'Sindex => Index of Point location :1,2,3,4,5,6
    Case 1
        'Nothing Here,Manunally Calculated
    Case 2
        If Kg_get_span_case(W, L, P1, D1, P2, D2) = 1 Then
            Kg_get_station_coordinate = CVErr(xlErrNA)
         Else
            Kg_get_station_coordinate = IIf((D1 < L / 2) And D1 <> 0, BasePoint + D1, CVErr(xlErrNA))

        End If
    Case 3
    'Point 3 Get Location
        Select Case Kg_get_span_case(W, L, P1, D1, P2, D2)
        Case 1
            Kg_get_station_coordinate = CVErr(xlErrNA)
        Case 2
        '[IF a>Span/2] D1 [X1 IF X<0]
           X = ((L - D1) * ((P1 * (L - D1) + (W * L * L) / 2) / L - P1 - W * D1)) / ((P1 + W * L - (P1 * (L - D1) + (W * L * L) / 2) / L) + ((P1 * (L - D1) + (W * L * L) / 2) / L - P1 - W * D1))
           If (D1 < L / 2) And (X <> L / 2) Then
                If X > 0 Then
                    Kg_get_station_coordinate = BasePoint + D1 + X
                Else
                    Kg_get_station_coordinate = BasePoint + D1
                End If
           Else
                Kg_get_station_coordinate = CVErr(xlErrNA)
           End If
        Case 3
            'D2[+X3 IF X<0]
            X = ((L - D2) * ((P1 * (L - D1) + P2 * (L - D2) + (W * L * L) / 2) / L - W * D1 - P1 - W * (D2 - D1) - P2)) / ((P1 + P2 + W * L - (P1 * (L - D1) + P2 * (L - D2) + (W * L * L) / 2) / L) + ((P1 * (L - D1) + P2 * (L - D2) + (W * L * L) / 2) / L - W * D1 - P1 - W * (D2 - D1) - P2))
            If X > 0 Then
                Kg_get_station_coordinate = BasePoint + D2 + X
            Else
                Kg_get_station_coordinate = IIf((D2 < L / 2), BasePoint + D2, CVErr(xlErrNA))
            End If
        Case 4
            'D1+X4[IF P1 & P2 Exist < Span/2]
            X = ((L / 2 - D1) * ((P1 * (L - D1) + (W * L * L) / 2 + P2 * L / 2) / L - P1 - W * D1)) / ((P1 + P2 + W * L - (P1 * (L - D1) + (W * L * L) / 2 + P2 * L / 2) / L - W * L / 2 - P2) + ((P1 * (L - D1) + (W * L * L) / 2 + P2 * L / 2) / L - P1 - W * D1))
            MsgBox X
            If D1 < L / 2 And D2 = L / 2 And X < (L / 2 - D1) Then
                If (X > 0) Then
                      Kg_get_station_coordinate = BasePoint + D1 + X
                Else
                       Kg_get_station_coordinate = BasePoint + D1
                End If
           Else
                Kg_get_station_coordinate = CVErr(xlErrNA)
           End If

        Case 5
            'D1[+X5 IF X5>L/2-D1]]
           X = ((D2 - D1) * ((P1 * (L - D1) + (W * L * L) / 2 + P2 * (L - D2)) / L - P1 - W * D1)) / (((P1 * (L - D1) + (W * L * L) / 2 + P2 * (L - D2)) / L - P1 - W * D1) + (P1 + W * L + P2 - (P1 * (L - D1) + (W * L * L) / 2 + P2 * (L - D2)) / L - W * (L - D2) - P2))
            If X > 0 And X < (L / 2 - D1) Then
                Kg_get_station_coordinate = BasePoint + D1 + X
            Else
                Kg_get_station_coordinate = CVErr(xlErrNA)
            End If
        End Select

    Case 4
        'Mid-Span
        Kg_get_station_coordinate = BasePoint + L / 2


    Case 5
        Select Case Kg_get_span_case(W, L, P1, D1, P2, D2)
        Case 1
            'NA For distributed
            Kg_get_station_coordinate = CVErr(xlErrNA)
        Case 2
            ' [IF a<Span/2]
             X = (D1 * ((P1 * (L - D1) + (W * L * L) / 2) / L)) / (-((P1 * (L - D1) + (W * L * L) / 2) / L - W * D1) + ((P1 * (L - D1) + (W * L * L) / 2) / L))
            If (D1 > L / 2) And D1 <> L Then
                If X > 0 Then
                    Kg_get_station_coordinate = BasePoint + X
                Else

                    Kg_get_station_coordinate = BasePoint + D1
                End If
            Else
                Kg_get_station_coordinate = CVErr(xlErrNA)
            End If

        Case 3
             'X32
            X = (D1 * ((P1 * (L - D1) + P2 * (L - D2) + (W * L * L) / 2) / L)) / (-((P1 * (L - D1) + P2 * (L - D2) + (W * L * L) / 2) / L - W * D1) + ((P1 * (L - D1) + P2 * (L - D2) + (W * L * L) / 2) / L))
           If X > L / 2 And X < D1 Then
                Kg_get_station_coordinate = BasePoint + X
            Else
                Kg_get_station_coordinate = CVErr(xlErrNA)
            End If
        Case 4
            'X5 [IF P1 & P2 Exist <Span/2]
            X = ((D2 - D1) * ((P1 * (L - D1) + (W * L * L) / 2 + P2 * (L - D2)) / L - P1 - W * D1)) / ((P1 + P2 + W * L - (P1 * (D2) + (W * L * L) / 2 + P2 * (L - D2)) / L - W * (L - D2) - P2) + ((P1 * (L - D1) + (W * L * L) / 2 + P2 * (L - D2)) / L - P1 - W * D1))

            If D1 = L / 2 And D2 > L / 2 Then
                If (X > 0) Then
                      Kg_get_station_coordinate = BasePoint + D1 + X
                Else
                       Kg_get_station_coordinate = CVErr(xlErrNA)  'D1 = L/2 [Already calculated]
                End If
           Else
                Kg_get_station_coordinate = CVErr(xlErrNA)
           End If

        Case 5
           'D1[+X5 IF X5<L/2-D1]]
          X = ((D2 - D1) * ((P1 * (L - D1) + (W * L * L) / 2 + P2 * (L - D2)) / L - P1 - W * D1)) / (((P1 * (L - D1) + (W * L * L) / 2 + P2 * (L - D2)) / L - P1 - W * D1) + (P1 + W * L + P2 - (P1 * (L - D1) + (W * L * L) / 2 + P2 * (L - D2)) / L - W * (L - D2) - P2))
             If X > (L / 2 - D1) Then
                If (X > 0) Then
                      Kg_get_station_coordinate = BasePoint + D1 + X
                Else
                       Kg_get_station_coordinate = BasePoint + D1
                End If
           Else
                Kg_get_station_coordinate = CVErr(xlErrNA)
           End If
        End Select

    Case 6
        Select Case Kg_get_span_case(W, L, P1, D1, P2, D2)
        Case 1
            Kg_get_station_coordinate = CVErr(xlErrNA)
        Case 2
            Kg_get_station_coordinate = IIf((D1 > L / 2) And D1 <> L, BasePoint + D1, CVErr(xlErrNA))
        Case 3
            Kg_get_station_coordinate = IIf(D1 > L / 2, BasePoint + D1, CVErr(xlErrNA))
        Case 4
            Kg_get_station_coordinate = IIf(D2 > L / 2, BasePoint + D2, CVErr(xlErrNA))
        Case 5
            Kg_get_station_coordinate = IIf(D2 > L / 2, BasePoint + D2, CVErr(xlErrNA))
        End Select
   Case Else
    Kg_get_station_coordinate = "NOT CALCULATED YET"

End Select
End Function


''Kg_Sort_Loads is a function used to sort two given loads by their distance and return the first & second load after sorting
' FOR Example IF we have P1=5t & Distance from left= 2m & P2=4t & Distance = 1m ->The function return P1=4t&A1=1m && P2=5t&A2=2m
' -------------------function parameters------------------------
'SortIndex  :: Index of Load|Distance Required
'PorA       :: Get Force Value or Get force distance
'P1|P2      :: Forces Value
'A1|A2      :: Forces Distance
Public Function kg_sort_loads(SortIndex As Integer, PorA As String, P1 As Double, A1 As Double, P2 As Double, A2 As Double)

     ''IF NOTHING IS GIVEN
    If P1 = 0 And P2 = 0 Then
    'END Function No sort required
    'Return 0 For all Fields
      kg_sort_loads = 0

      'END FUNCTION TO STOP IT FROM CONTINUE
      Exit Function
    End If


    '' IF THERE IS ONLY ONE FORCE GIVEN
    If P1 = 0 Or P2 = 0 Then
    'P1 or P2 = Zero
        If (P2 = 0 And P1 <> 0) Then
        'Return P1 & A1
            If SortIndex = 1 Then
                If (PorA = "P") Then
                    kg_sort_loads = P1
                Else
                    kg_sort_loads = A1
                End If
            Else
               'IF there is only one force => No Need for Force 2
                kg_sort_loads = 0
            End If
        Else
        'Return P2 & A2
            If SortIndex = 1 Then
                If (PorA = "P") Then
                    kg_sort_loads = P2
                Else
                    kg_sort_loads = A2
                End If
            Else
               'IF there is only one force => Use only one force as min
                kg_sort_loads = 0
            End If
        End If
       Exit Function
    End If


    ''IF TWO FORCES ARE GIVEN

   'FIRST IF USER PUT TWO FORCES WITH SAME DISTANCE -> MAKE THEM ONE
    If P1 <> 0 And P2 <> 0 And A1 = A2 Then
            If SortIndex = 1 Then
                If (PorA = "P") Then
                    kg_sort_loads = P1 + P2
                Else
                    kg_sort_loads = A1
                End If
            Else
               'IF there is only one force => No Need for Force 2
                kg_sort_loads = 0
            End If
        Exit Function
    End If

    'Second ,IF Two Forces given, Compare distances
    If A1 < A2 Then
        If SortIndex = 1 Then
            If (PorA = "P") Then
                kg_sort_loads = P1
            Else
                kg_sort_loads = A1
            End If
        Else
            If (PorA = "P") Then
                kg_sort_loads = P2
            Else
                kg_sort_loads = A2
            End If
        End If
    Else
        If SortIndex = 1 Then
            If (PorA = "P") Then
                kg_sort_loads = P2
            Else
                kg_sort_loads = A2
            End If
        Else
            If (PorA = "P") Then
                kg_sort_loads = P1
            Else
                kg_sort_loads = A1
            End If
        End If
    End If

End Function


Public Function kg_Elastic_Reaction(Direction As String, SPAN As Double, DISTLOAD As Double, P1 As Double, A1 As Double, P2 As Double, A2 As Double, CantliverMoment As Double)
  Dim R As Double, E1 As Double, E2 As Double

    If DISTLOAD <> 0 Then
    '1- Elastic Reaction due to DISTLOAD
         R = DISTLOAD * (SPAN * SPAN * SPAN) / 24
    End If

        If Direction = "Right" Then
        'Right [R2]
            '2- Elastic Reaction due to P1 (IF EXIST)
            If P1 <> 0 Then
                E1 = 0.5 * A1 * ((P1 * A1 * (SPAN - A1)) / SPAN)
                E2 = 0.5 * (SPAN - A1) * ((P1 * A1 * (SPAN - A1)) / SPAN)
                R = R + (((E1 * 2 / 3 * A1) + (E2 * (A1 + (1 / 3 * (SPAN - A1))))) / SPAN)
            End If
            If P2 <> 0 Then
            '3- Elastic Reaction due to P2 (IF EXIST)
                E1 = 0.5 * A2 * ((P2 * A2 * (SPAN - A2)) / SPAN)
                E2 = 0.5 * (SPAN - A2) * ((P2 * A2 * (SPAN - A2)) / SPAN)
                R = R + (((E1 * 2 / 3 * A2) + (E2 * (A2 + (1 / 3 * (SPAN - A2))))) / SPAN)
            End If
            If CantliverMoment <> 0 Then
                ' R1-LEFT = 1/3 * M * L
                ' The Sign is +ve As CantliverMoment value paramter is negative So R1 will be negative
                R = R + (1 / 3 * CantliverMoment * SPAN)
            End If
        Else
            'Left[R1]
                If P1 <> 0 Then
                    E1 = 0.5 * A1 * ((P1 * A1 * (SPAN - A1)) / SPAN)
                    E2 = 0.5 * (SPAN - A1) * ((P1 * A1 * (SPAN - A1)) / SPAN)
                    R = R + (((E2 * 2 / 3 * (SPAN - A1)) + (E1 * ((SPAN - A1) + (1 / 3 * A1)))) / SPAN)
                End If
                If P2 <> 0 Then
                    E1 = 0.5 * A2 * ((P2 * A2 * (SPAN - A2)) / SPAN)
                    E2 = 0.5 * (SPAN - A2) * ((P2 * A2 * (SPAN - A2)) / SPAN)
                    R = R + (((E2 * 2 / 3 * (SPAN - A2)) + (E1 * ((SPAN - A2) + (1 / 3 * A2)))) / SPAN)
                End If
                If CantliverMoment <> 0 Then
                ' R2-RIGHT = 1/6 * M * L
                ' TODO - IF CANTLIVER IS AT START | NO NEED FOR THIS FOR NOW
                R = R + (1 / 6 * CantliverMoment * SPAN)

            End If
        End If
    kg_Elastic_Reaction = R
End Function


Public Function Kg_Ngtv_Moment_Calculator(Spans_Count As String, rtrn As String, range As range, Cantliver_moment As Double)

       Kg_Moment_Calculator = (range.Cells(0))
'      Select Case Spans_Count
'        Case "ONE"
'            Kg_Moment_Calculator = 0
'        Case "ONE-CNTLVR"
'            Kg_Moment_Calculator = Cantliver_moment
'        Case "TWO"
'             Select Case rtrn
'            Case "M1"
'                Kg_Moment_Calculator = (range.Cells(1, 1))
'            Case "Mc"
'
'            End Select
'
'        Case Else
'        '      Kg_Moment_Calculator = "ERROR"
'        End Select
End Function

Public Function Kg_Spans_counter(range As range, Last_span_as_cantliver As String)
Dim S1, S2, S3, S4, S5 As Double
S1 = range.Cells(1)
S2 = range.Cells(2)
S3 = range.Cells(3)
S4 = range.Cells(4)
S5 = range.Cells(5)

 If (Application.WorksheetFunction.Max(S5, S4, S3, S2) = 0) Then
    If (Last_span_as_cantliver = "YES") Then
      Kg_Spans_counter = "CNTLVR"
    Else
      Kg_Spans_counter = "ONE"
    End If
 ElseIf (Application.WorksheetFunction.Max(S5, S4, S3) = 0) Then
    If (Last_span_as_cantliver = "YES") Then
      Kg_Spans_counter = "ONE-CNTLVR"
    Else
      Kg_Spans_counter = "TWO"
    End If
  ElseIf (Application.WorksheetFunction.Max(S5, S4) = 0) Then
    If (Last_span_as_cantliver = "YES") Then
      Kg_Spans_counter = "TWO-CNTLVR"
    Else
      Kg_Spans_counter = "THREE"
     End If
  ElseIf (Application.WorksheetFunction.Max(S5) = 0) Then
    If (Last_span_as_cantliver = "YES") Then
      Kg_Spans_counter = "THREE-CNTLVR"
    Else
      Kg_Spans_counter = "FOUR"
     End If
  Else
     If (Last_span_as_cantliver = "YES") Then
      Kg_Spans_counter = "FOUR-CNTLVR"
    Else
      Kg_Spans_counter = "FIVE"
     End If
   End If

End Function