SHRIMP: Sub SetSKageForCPb

SQUID 2.50 Sub: SetSKageForCPb

This subroutine (which is solely for Grouped-sample sheets in Group Me sequences where pbGrpCommPbSpecific = FALSE) implements iterative polishing of the Stecey-Kramers model common-Pb age on a post-by-spot basis, to match the preferred (common-Pb corrected) Group Date Type defined by the user.

Usage

SetSKageForCPb FirstRw, LastRw, GrpAgeTypeCol, SKageCol, NumIters

Mandatory variables

FirstRw: Integer index number of the first row containing spot-by-spot data.
LastRw: Integer index number of the last row containing spot-by-spot data.
GrpAgeTypeCol: Integer index number of the column containing the user-preferred Group Date Type.
SKageCol: Integer index number of the column containing the Stacey-Kramers model age value ["Age S-K ComPb"].
NumIters: Integer number of iterationsto be performed as part of the polishing process.

---

Definition of variables

Values of type Integer
i, Iter

Values of type Variant
TempVal

Values of type Double
AgeVal, SK_Age

---

In Excel, this subroutine comprises nothing more than a matching of GrpAgeTypeCol[i] and SKageCol[i], followed by a re-evaluation of the formula linking the two. The rest of the subroutine is error-trapping to reflect that only dates between 0 Ma and 3700 Ma are suitable GrpAgeTypeCol[i] values from which to start.

For Iter = 1 To NumIters --number of times to iterate

  For i = FirstRw To LastRw --row-by-row calculations

    TempVal = GrpAgeTypeCol[i]

    If IsNumeric(TempVal) = TRUE 
  
      AgeVal = GrpAgeTypeCol[i] --remember values are always Ma in SQUID 2.50!
                                                                
      If (AgeVal < 0) OR (AgeVal > 3700)
        SK_Age = MIN( MAX( AgeVal, 0 ), 3700 )
      Else
        SK_Age = MIN( 3700, MAX( GrpAgeTypeCol[i], 0 ) )
      End If
                                                                  
    Else --IsNumeric(TempVal) = FALSE
  
      SK_Age = 0
   
    End If
    
    SKageCol[i] = SK_Age
  
  Next i

  [APPLICATION.CALCULATE/EVALUTE]
  
Next Iter

End Sub