我有以下单元格:
matr = '01/07/2012' '00:00' [ 0.2000]
'05/07/2012' '17:00' [ 1]
'05/07/2012' '20:00' [ 8.4000]
'05/07/2012' '21:00' [ 1.2000]
'06/07/2012' '02:00' [ 0.4000]
'06/07/2012' '19:00' [ 5]
'07/07/2012' '01:00' [ 7]
'08/07/2012' '00:00' [ 4.2000]
'08/07/2012' '01:00' [ 3]
'08/07/2012' '04:00' [ 0.2000]
'09/07/2012' '16:00' [ 0.2000]
'09/07/2012' '23:00' [ 3]
'22/07/2012' '20:00' [ 4.2000]
'23/07/2012' '20:00' [ 1.2000]
'23/07/2012' '22:00' [ 5.4000]
'25/07/2012' '22:00' [14.6000]
'27/07/2012' '21:00' [ 0.2000]
'28/07/2012' '23:00' [ 0.2000]
'30/07/2012' '20:00' [ 0.2000]
我只想选择 20:00 到 23:00 之间的信息。一旦 matr(:,2) 是字符串信息,我该如何继续?