x2mdate() converts from excel serial date number to Matlab serial date number. An optional 3rd input allows you to convert the excel date to Matlab's datetime format.
MATLABDate = x2mdate(dateSamples, 0,'datetime')
---[Update]---
Use readtable() to read in the excel table.
opts = spreadsheetImportOptions('NumVariables',9, ...
'VariableTypes', {'char','char','datetime','double','double','double','double','double','double'},...
'VariableNamesRange', 'A1', 'DataRange', 'A2');
T = readtable('ausdata.xlsx', opts);
% Look at first few rows
head(T)
% 8×9 table
% Date Hour Var3 DryBulb DewPnt WetBulb Humidity ElecPrice SYSLoad
% _______________ ____________ ____ _______ ______ _______ ________ _________ _______
% {'01-Jan-2006'} {'0.020833'} NaT 23.9 21.65 22.4 87.5 19.67 8013.3
% {'01-Jan-2006'} {'0.041667'} NaT 23.9 21.7 22.4 88 18.56 7726.9
% {'01-Jan-2006'} {'0.0625' } NaT 23.8 21.65 22.35 88 19.09 7372.9
% {'01-Jan-2006'} {'0.083333'} NaT 23.7 21.6 22.3 88 17.4 7071.8
% {'01-Jan-2006'} {'0.10417' } NaT 23.7 21.6 22.3 88 17 6865.4
% {'01-Jan-2006'} {'0.125' } NaT 23.7 21.6 22.3 88 17 6685.9
% {'01-Jan-2006'} {'0.14583' } NaT 23.6 21.65 22.3 89 17 6548.6
% {'01-Jan-2006'} {'0.16667' } NaT 23.5 21.7 22.3 90 16.92 6487.8
The NaT values in column 3 in my example may be due to a difference in the version of Excel I'm currently using.
If you're also getting NaT values in column 3 you can recreate the datetime values using this,
T.Properties.VariableNames{3} = 'datetime';
T.datetime = dateshift(T.Date,'start','day') + T.Hour;
% head(T)
% Date Hour datetime DryBulb DewPnt WetBulb Humidity ElecPrice SYSLoad
% ___________ _________ ____________________ _______ ______ _______ ________ _________ _______
% 01-Jan-2006 1800 sec 01-Jan-2006 00:30:00 23.9 21.65 22.4 87.5 19.67 8013.3
% 01-Jan-2006 3600 sec 01-Jan-2006 01:00:00 23.9 21.7 22.4 88 18.56 7726.9
% 01-Jan-2006 5400 sec 01-Jan-2006 01:30:00 23.8 21.65 22.35 88 19.09 7372.9
% 01-Jan-2006 7200 sec 01-Jan-2006 01:59:59 23.7 21.6 22.3 88 17.4 7071.8
% 01-Jan-2006 9000 sec 01-Jan-2006 02:30:00 23.7 21.6 22.3 88 17 6865.4
% 01-Jan-2006 10800 sec 01-Jan-2006 03:00:00 23.7 21.6 22.3 88 17 6685.9
% 01-Jan-2006 12600 sec 01-Jan-2006 03:29:59 23.6 21.65 22.3 89 17 6548.6
% 01-Jan-2006 14400 sec 01-Jan-2006 03:59:59 23.5 21.7 22.3 90 16.92 6487.8
