Converting cell array containing date strings to weekday?

Hello, I have a 366*1 cell array containing date string such as '2015-01-01'. I want to change this date string to weekday such as Monday, Tuesday..etc. What function should I have to use? Thanks!

Answer 1

[Star Strider]

Use the weekday function:

date_cell = {'2015-01-01'; '2015-01-02'; '2015-01-03'};
dn = datenum(date_cell, 'yyyy-mm-dd');
[~,DayOfWeek] = weekday(dn,'long')

DayOfWeek =

    3×8 char array

      'Thursday'
      'Friday  '
      'Saturday'

[Jinah Lee]

Thank you for your answer, However, I got error message said 'Error using weekday (line 49) DATENUM failed.' I used this code...

t = rawData(:,1);
dn = {t,'yyyy-mm-dd'};
[~,DayofWeek] = weekday(dn,'long');
DayofWeek

[Star Strider]

My pleasure.

I have no idea what your ‘rawData’ has. The syntax you are using does not appear to be correct.

Try this:

dn = datenum(rawData{:}(:,1), 'yyyy-mm-dd');
[~,DayOfWeek] = weekday(dn,'long')

Without your ‘rawData’ cell array, I cannot test this, so I am guessing this is the correct way to address your cell array.

[Jinah Lee]

This is part of 1st column of rawData. So 1st column of rawdata is a cell array containing bunch of data strings.. and I want to change this into weekday so that I could calculate average of certain values per weekday..

'Date'
  '2015-01-01'
  '2015-01-02'
  '2015-01-03'
  '2015-01-04'
  '2015-01-05'
  '2015-01-06'
  '2015-01-07'
  '2015-01-08'
  '2015-01-09'

[Star Strider]

I had to create a cell array that resembled yours in order to get the addressing correct.

This works:

rawData = {'Date' 'Number'; '2015-01-01' 10; '2015-01-02'  5; '2015-01-03'  7};
dv = {rawData{2:end,1}};
dn = datenum(dv, 'yyyy-mm-dd');
[~,DayOfWeek] = weekday(dn,'long')