Compilation 子行给出编译错误：未定义变量

在尝试运行代码时，我得到一个错误

“compile error:variable not defined”

，它突出显示了我的子行。这是代码供参考

Sub RI_Processing()
    Dim i As Single
    Dim Output() As Single 'Define this dynamic array for the solver output

Process the DMSO data
    For i = 1 To 45 Step 1
        Workbooks("Calibration Range 1 Normalized Profiles.xlsx").Activate
        RawData.Range("C10:C649") = Sheet1.Columns("i").Values
        SolverOk SetCell:="$E$7", MaxMinVal:=2, ValueOf:=0, ByChange:="$B$2:$B$4", _
        Engine:=1, EngineDesc:="GRG Nonlinear"
        SolverSolve
        Workbooks("Simulated Fresnel Function.xlsx").Activate
        Output(i, 1) = Sheet1.Range("B4").Values

    Next i

    i = 0

    ' Process the NaCl Data
    For i = 1 To 102 Step 1
        Workbooks("Calibration Range 1 Normalized Profiles.xlsx").Activate
        RawData.Range("C10:C649") = Sheet2.Columns("i").Values
        SolverOk SetCell:="$E$7", MaxMinVal:=2, ValueOf:=0, ByChange:="$B$2:$B$4", _
        Engine:=1, EngineDesc:="GRG Nonlinear"
        SolverSolve
        Workbooks("Simulated Fresnel Function.xlsx").Activate
        Output(i, 2) = Sheet1.Range("B4").Values

    Next i

    i = 0

    ' Process the Sucrose data
    For i = 1 To 72 Step 1
        Workbooks("Calibration Range 1 Normalized Profiles.xlsx").Activate
        RawData.Range("C10:C649") = Sheet3.Columns("i").Values 'Copies the data of all 'i' columns to raw data for solver
        SolverOk SetCell:="$E$7", MaxMinVal:=2, ValueOf:=0, ByChange:="$B$2:$B$4", _
        Engine:=1, EngineDesc:="GRG Nonlinear"
        SolverSolve 'Run solver
        Workbooks("Simulated Fresnel Function.xlsx").Activate
        Output(i, 3) = Sheet1.Range("B4").Values 'Put solver output to the matrix 'output' in the appropriate columns

    Next i

End Sub