時間範囲判定応用: A列に日付､B列に時間､C列に値が設定されている履歴データの指定時間範囲内のC列の値の平均値を取得する

＜分類：値取得＞
＜使用例：対象範囲(開始)の日付(2019/8/16)時間(02:00:00)～対象範囲(終了)の日付(2019/8/16)時間(13:00:00)の平均値(30.375)を取得する＞
＜注意：サンプルデータを作成するプログラムになっていますので、Sheet1は何もデータがないシートをご用意ください＞
＜プログラム例＞

Sub 使用例()
   Dim fdate As Date
   Dim ftime As Date
   Dim gdate As Date
   Dim gtime As Date
   Dim tdate As Date
   Dim ttime As Date
   Dim i As Long
   Dim goukei As Single
   Dim gcnt As long
   
   Worksheets("Sheet1").Select
   
  'サンプルデータ作成
   Cells(1, 1) = "2019/8/16"
   Cells(1, 2) = "00:00:00"
   Cells(1, 3) = "28.7"
   
   Cells(2, 1) = "2019/8/16"
   Cells(2, 2) = "01:00:00"
   Cells(2, 3) = "29.0"
   
   Cells(3, 1) = "2019/8/16"
   Cells(3, 2) = "02:00:00"
   Cells(3, 3) = "29.1"
   
   Cells(4, 1) = "2019/8/16"
   Cells(4, 2) = "03:00:00"
   Cells(4, 3) = "29.1"
   
   Cells(5, 1) = "2019/8/16"
   Cells(5, 2) = "04:00:00"
   Cells(5, 3) = "29.2"
   
   Cells(6, 1) = "2019/8/16"
   Cells(6, 2) = "05:00:00"
   Cells(6, 3) = "29.1"
   
   Cells(7, 1) = "2019/8/16"
   Cells(7, 2) = "06:00:00"
   Cells(7, 3) = "29.1"
   
   Cells(8, 1) = "2019/8/16"
   Cells(8, 2) = "07:00:00"
   Cells(8, 3) = "29.5"
   
   Cells(9, 1) = "2019/8/16"
   Cells(9, 2) = "08:00:00"
   Cells(9, 3) = "30.1"
   
   Cells(10, 1) = "2019/8/16"
   Cells(10, 2) = "09:00:00"
   Cells(10, 3) = "31.6"
   
   Cells(11, 1) = "2019/8/16"
   Cells(11, 2) = "10:00:00"
   Cells(11, 3) = "32.5"
   
   Cells(12, 1) = "2019/8/16"
   Cells(12, 2) = "11:00:00"
   Cells(12, 3) = "31.7"
   
   Cells(13, 1) = "2019/8/16"
   Cells(13, 2) = "12:00:00"
   Cells(13, 3) = "32.2"
   
   Cells(14, 1) = "2019/8/16"
   Cells(14, 2) = "13:00:00"
   Cells(14, 3) = "31.3"
   
   Cells(15, 1) = "2019/8/16"
   Cells(15, 2) = "14:00:00"
   Cells(15, 3) = "31.6"
   
   Cells(16, 1) = "2019/8/16"
   Cells(16, 2) = "15:00:00"
   Cells(16, 3) = "30.9"
   
   Cells(17, 1) = "2019/8/16"
   Cells(17, 2) = "16:00:00"
   Cells(17, 3) = "30.8"
   
   Cells(18, 1) = "2019/8/16"
   Cells(18, 2) = "17:00:00"
   Cells(18, 3) = "26.9"
   
   Cells(19, 1) = "2019/8/16"
   Cells(19, 2) = "18:00:00"
   Cells(19, 3) = "27.7"
   
   Cells(20, 1) = "2019/8/16"
   Cells(20, 2) = "19:00:00"
   Cells(20, 3) = "28.0"
   
   Cells(21, 1) = "2019/8/16"
   Cells(21, 2) = "20:00:00"
   Cells(21, 3) = "28.3"
   
   Cells(22, 1) = "2019/8/16"
   Cells(22, 2) = "21:00:00"
   Cells(22, 3) = "28.8"
   
   Cells(23, 1) = "2019/8/16"
   Cells(23, 2) = "22:00:00"
   Cells(23, 3) = "29.0"
   
   Cells(24, 1) = "2019/8/16"
   Cells(24, 2) = "23:00:00"
   Cells(24, 3) = "28.7"
   
   fdate = "2019/8/16"
   ftime = "02:00:00"
   
   tdate = "2019/8/16"
   ttime = "13:00:00"
   
   goukei = 0
   gcnt = 0
   i = 1
   Do While Cells(i, 1) <> ""
          
      gdate = Cells(i, 1)
      gtime = Cells(i, 2)
      
      If 時間範囲判定(fdate, ftime, gdate, gtime, tdate, ttime) = "内" Then
         goukei = goukei + Cells(i, 3)
         gcnt = gcnt + 1
      End If
   
      i = i + 1
   Loop
   
   MsgBox ("平均は" & goukei / gcnt & "です")
   

End Sub

Function 時間範囲判定(fdate As Date, ftime As Date, gdate As Date, gtime As Date, tdate As Date, ttime As Date)

    Dim fr As String
    Dim tr As String
    Dim ftr As String
    
    If DateDiff("d", fdate, gdate) > 0 Then
       fr = "大"
    End If

    If DateDiff("d", fdate, gdate) = 0 Then
       
       If DateDiff("s", ftime, gtime) >= 0 Then
          fr = "大"
       Else
          fr = "小"
       End If
    End If

    If DateDiff("d", fdate, gdate) < 0 Then
       fr = "小"
    End If
    
    If DateDiff("d", gdate, tdate) > 0 Then
       tr = "大"
    End If

    If DateDiff("d", gdate, tdate) = 0 Then
       
       If DateDiff("s", gtime, ttime) >= 0 Then
          tr = "大"
       Else
          tr = "小"
       End If
    End If

    If DateDiff("d", gdate, tdate) < 0 Then
       tr = "小"
    End If
    
    ftr = fr & tr
    
    Select Case ftr
           Case "大大"
               時間範囲判定 = "内"
           Case Else
               時間範囲判定 = "外"
    End Select
    
End Function