How to request additional data from the user in a function

Hi, Thanks for reading this.

I have to call a function, then it appears I need to request more data from within the function. Data the user is supposed to type on the screen. How do I do this? The problem is stated as:

I have to admit I'm a little unclear with regard to what the problem statement is requesting.

[Jiro Doke]

Take a look at this example:

Create a Structure Array

The output to your problem would be something similar to "patient array" in the above example, where there will be N elements based on the input you provide. For example, if the input is 2 (February), there are 29 days in Feb 2016, so the struct array will have 29 elements, where each element corresponds to each day of the month.

This should be enough to get you started.

BTW, the question doesn't seem to state that you need to request additional data from within the function. The function simply takes in one input argument, and that's it.

[DJ V]

THe issue of data accepted is the confusing part. IF the Matlab function only takes in a single digit indicating the month, how do I get the day of the month desired? It appears to require a second query within the function.

[Stephen23]

" It appears to require a second query within the function."

No, have a look at the example that you have been given. Selecting the day occurs by indexing into the output variable m, not by an input argument to the function. The output variable needs to contain all days for the selected month.

[DJ V]

I'm getting an error in the following code:

The error is:

In an assignment A(:) = B, the number of elements in A and B must be the same.

It occurs when I start assigning dayvalues to dates in the loop for "1" or January for 2016, using "m = year2016(1)" as my function call. Why is this happening? How do I fix it?

function S = year2016( i)
%YEAR2016 Summary of this function goes here
%   Detailed explanation goes here
cest=true;
for month = 1:12
    if i == month
        cest = false;
    end
    if month ==12 && cest == true
        S = [];
        break;
    end
end
dayvalue=(31);
if i ==4 || i == 9 ||i == 11 || i ==6
   if i ==4
       monthvalue ='April';
       for n = 1 to 30
           datevalue(n) =n;
       end
   dayvalue(1)='Fri';
   dayvalue(2)='Sat';
   dayvalue(3)='Sun';
   dayvalue(4)='Mon';
   dayvalue(5)='Tue';
   dayvalue(6)='Wed';
   dayvalue(7)='Thu';
   dayvalue(8)='Fri';
   dayvalue(9)='Sat';
   dayvalue(10)='Sun';
   dayvalue(11)='Mon';
   dayvalue(12)='Tue';
   dayvalue(13)='Wed';
   dayvalue(14)='Thu';
   dayvalue(15)= 'Fri';
   dayvalue(16)='Sat';
   dayvalue(17)='Sun';
   dayvalue(18)='Mon';
   dayvalue(19)='Tue';
   dayvalue(20)='Wed';
   dayvalue(21)='Thu';
   dayvalue(22)='Fri';
   dayvalue(23)='Sat';
   dayvalue(24)='Sun';
   dayvalue(25)='Mon';
   dayvalue(26)='Tue';
   dayvalue(27)='Wed';
   dayvalue(28)='Thu';
   dayvalue(29)='Fri';
   dayvalue(30)='Sat';
end
   if i == 6
       monthvalue ='June';
       for n = 1 to 30
           datevalue(n) =n;
       end
   dayvalue(1)='Wed';
   dayvalue(2)='Thu';
   dayvalue(3)='Fri';
   dayvalue(4)='Sat';
   dayvalue(5)='Sun';
   dayvalue(6)='Mon';
   dayvalue(7)='Tue';
   dayvalue(8)='Wed';
   dayvalue(9)='Thu';
   dayvalue(10)= 'Fri';
   dayvalue(11)='Sat';
   dayvalue(12)='Sun';
   dayvalue(13)='Mon';
   dayvalue(14)='Tue';
   dayvalue(15)='Wed';
   dayvalue(16)='Thu';
   dayvalue(17)='Fri';
   dayvalue(18)='Sat';
   dayvalue(19)='Sun';
   dayvalue(20)='Mon';
   dayvalue(21)='Tue';
   dayvalue(22)='Wed';
   dayvalue(23)='Thu';
   dayvalue(24)='Fri';
   dayvalue(25)='Sat';
   dayvalue(26)='Sun';
   dayvalue(27)='Mon';
   dayvalue(28)='Tue';
   dayvalue(29)='Wed';
   dayvalue(30)='Thu';
   end
   if i == 9
       monthvalue =' September';
       for n = 1 to 30
           datevalue(n) =n;
       end
   dayvalue(1)='Thu';
   dayvalue(2)='Fri';
   dayvalue(3)='Sat';
   dayvalue(4)='Sun';
   dayvalue(5)='Mon';
   dayvalue(6)='Tue';
   dayvalue(7)='Wed';
   dayvalue(8)='Thu';
   dayvalue(9)= 'Fri';
   dayvalue(10)='Sat';
   dayvalue(11)='Sun';
   dayvalue(12)='Mon';
   dayvalue(13)='Tue';
   dayvalue(14)='Wed';
   dayvalue(15)='Thu';
   dayvalue(16)='Fri';
   dayvalue(17)='Sat';
   dayvalue(18)='Sun';
   dayvalue(19)='Mon';
   dayvalue(20)='Tue';
   dayvalue(21)='Wed';
   dayvalue(22)='Thu';
   dayvalue(23)='Fri';
   dayvalue(24)='Sat';
   dayvalue(25)='Sun';
   dayvalue(26)='Mon';
   dayvalue(27)='Tue';
   dayvalue(28)='Wed';
   dayvalue(29)='Thu';
   dayvalue(30)='Fri';
end
   if i == 11
       monthvalue = 'November';
       for n = 1 to 30
           datevalue(n) =n;
       end
   dayvalue(1)='Tue';
   dayvalue(2)='Wed';
   dayvalue(3)='Thu';
   dayvalue(4)='Fri';
   dayvalue(5)='Sat';
   dayvalue(6)='Sun';
   dayvalue(7)='Mon';
   dayvalue(8)='Tue';
   dayvalue(9)='Wed';
   dayvalue(10)='Thu';
   dayvalue(11)= 'Fri';
   dayvalue(12)='Sat';
   dayvalue(13)='Sun';
   dayvalue(14)='Mon';
   dayvalue(15)='Tue';
   dayvalue(16)='Wed';
   dayvalue(17)='Thu';
   dayvalue(18)='Fri';
   dayvalue(19)='Sat';
   dayvalue(20)='Sun';
   dayvalue(21)='Mon';
   dayvalue(22)='Tue';
   dayvalue(23)='Wed';
   dayvalue(24)='Thu';
   dayvalue(25)='Fri';
   dayvalue(26)='Sat';
   dayvalue(27)='Sun';
   dayvalue(28)='Mon';
   dayvalue(29)='Tue';
   dayvalue(30)='Wed';
   end
if i ==2
        monthvalue = 'February';
        for n = 1 to 28
            datevalue(n) = n
        end
   dayvalue(1)='Mon';
   dayvalue(2)='Tue';
   dayvalue(3)='Wed';
   dayvalue(4)='Thu';
   dayvalue(5)='Fri';
   dayvalue(6)='Sat';
   dayvalue(7)='Sun';
   dayvalue(8)='Mon';
   dayvalue(9)='Tue';
   dayvalue(10)='Wed';
   dayvalue(11)='Thu';
   dayvalue(12)='Fri';
   dayvalue(13)='Sat';
   dayvalue(14)='Sun';
   dayvalue(15)='Mon';
   dayvalue(16)='Tue';
   dayvalue(17)='Wed';
   dayvalue(18)='Thu';
   dayvalue(19)='Fri';
   dayvalue(20)='Sat';
   dayvalue(21)='Sun';
   dayvalue(22)='Mon';
   dayvalue(23)='Tue';
   dayvalue(24)='Wed';
   dayvalue(25)='Thu';
   dayvalue(26)='Fri';
   dayvalue(27)='Sat';
   dayvalue(28)='Sun';
   dayvalue(29)='Mon';
end
end
if i==1||i ==3||i==5||i == 7||i==8||i ==10||i ==12
if i == 1        
        for n = 1:31
           datevalue(n) =n;
        end
   dayvalue(1)='Fri';
   dayvalue(2)='Sat';
   dayvalue(3)='Sun';
   dayvelue(4)='Mon';
   dayvalue(5)='Tue';
   dayvalue(6)='Wed';
   dayvalue(7)='Thu';
   dayvalue(8)='Fri';
   dayvalue(9)='Sat';
   dayvalue(10)='Sun';
   dayvalue(11)='Mon';
   dayvalue(12)='Tue';
   dayvalue(13)='Wed';
   dayvalue(14)='Thu';
   dayvalue(15)= 'Fri';
   dayvalue(16)='Sat';
   dayvalue(17)='Sun';
   dayvalue(18)='Mon';
   dayvalue(19)='Tue';
   dayvalue(20)='Wed';
   dayvalue(21)='Thu';
   dayvalue(22)='Fri';
   dayvalue(23)='Sat';
   dayvalue(24)='Sun';
   dayvalue(25)='Mon';
   dayvalue(26)='Tue';
   dayvalue(27)='Wed';
   dayvalue(28)='Thu';
   dayvalue(29)='Fri';
   dayvalue(30)='Sat';
   dayvalue(31)='Sun';
end
if i == 3       
        for n = 1: 31
           datevalue(n) =n;
        end
   dayvalue(1)='Tue';
   dayvalue(2)='Wed';
   dayvalue(3)='Thu';
   dayvalue(4)='Fri';
   dayvalue(5)='Sat';
   dayvalue(6)='Sun';
   dayvalue(7)='Mon';
   dayvalue(8)='Tue';
   dayvalue(9)='Wed';
   dayvalue(10)='Thu';
   dayvalue(11)= 'Fri';
   dayvalue(12)='Sat';
   dayvalue(13)='Sun';
   dayvalue(14)='Mon';
   dayvalue(15)='Tue';
   dayvalue(16)='Wed';
   dayvalue(17)='Thu';
   dayvalue(18)='Fri';
   dayvalue(19)='Sat';
   dayvalue(20)='Sun';
   dayvalue(21)='Mon';
   dayvalue(22)='Tue';
   dayvalue(23)='Wed';
   dayvalue(24)='Thu';
   dayvalue(25)='Fri';
   dayvalue(26)='Sat';
   dayvalue(27)='Sun';
   dayvalue(28)='Mon';
   dayvalue(29)='Tue';
   dayvalue(30)='Wed';
   dayvalue(31)='Thu';
end  
if i == 5       
        for n = 1 :31
           datevalue(n) =n;
        end
   dayvalue(1)='Sun';
   dayvalue(2)='Mon';
   dayvalue(3)='Tue';
   dayvalue(4)='Wed';
   dayvalue(5)='Thu';
   dayvalue(6)= 'Fri';
   dayvalue(7)='Sat';
   dayvalue(8)='Sun';
   dayvalue(9)='Mon';
   dayvalue(10)='Tue';
   dayvalue(11)='Wed';
   dayvalue(12)='Thu';
   dayvalue(13)='Fri';
   dayvalue(14)='Sat';
   dayvalue(15)='Sun';
   dayvalue(16)='Mon';
   dayvalue(17)='Tue';
   dayvalue(18)='Wed';
   dayvalue(19)='Thu';
   dayvalue(20)='Fri';
   dayvalue(21)='Sat';
   dayvalue(22)='Sun';
   dayvalue(23)='Mon';
   dayvalue(24)='Tue';
   dayvalue(25)='Wed';
   dayvalue(26)='Thu';
   dayvalue(27)='Fri';
   dayvalue(28)='Sat';
   dayvalue(29)='Sun';
   dayvalue(30)='Mon';
   dayvalue(31)='Tue';
end    
if i == 7       
        for n = 1:31
           datevalue(n) =n;
        end
   dayvalue(1)='Fri';
   dayvalue(2)='Sat';
   dayvalue(3)='Sun';
   dayvelue(4)='Mon';
   dayvalue(5)='Tue';
   dayvalue(6)='Wed';
   dayvalue(7)='Thu';
   dayvalue(8)='Fri';
   dayvalue(9)='Sat';
   dayvalue(10)='Sun';
   dayvalue(11)='Mon';
   dayvalue(12)='Tue';
   dayvalue(13)='Wed';
   dayvalue(14)='Thu';
   dayvalue(15)= 'Fri';
   dayvalue(16)='Sat';
   dayvalue(17)='Sun';
   dayvalue(18)='Mon';
   dayvalue(19)='Tue';
   dayvalue(20)='Wed';
   dayvalue(21)='Thu';
   dayvalue(22)='Fri';
   dayvalue(23)='Sat';
   dayvalue(24)='Sun';
   dayvalue(25)='Mon';
   dayvalue(26)='Tue';
   dayvalue(27)='Wed';
   dayvalue(28)='Thu';
   dayvalue(29)='Fri';
   dayvalue(30)='Sat';
   dayvalue(31)='Sun';
end     
if i == 8       
        for n = 1 :31
           datevalue(n) =n;
        end
   dayvalue(1)='Mon';
   dayvalue(2)='Tue';
   dayvalue(3)='Wed';
   dayvalue(4)='Thu';
   dayvalue(5)='Fri';
   dayvalue(6)='Sat';
   dayvalue(7)='Sun';
   dayvalue(8)='Mon';
   dayvalue(9)='Tue';
   dayvalue(10)='Wed';
   dayvalue(11)='Thu';
   dayvalue(12)='Fri';
   dayvalue(13)='Sat';
   dayvalue(14)='Sun';
   dayvalue(15)='Mon';
   dayvalue(16)='Tue';
   dayvalue(17)='Wed';
   dayvalue(18)='Thu';
   dayvalue(19)='Fri';
   dayvalue(20)='Sat';
   dayvalue(21)='Sun';
   dayvalue(22)='Mon';
   dayvalue(23)='Tue';
   dayvalue(24)='Wed';
   dayvalue(25)='Thu';
   dayvalue(26)='Fri';
   dayvalue(27)='Sat';
   dayvalue(28)='Sun';
   dayvalue(29)='Mon';
   dayvalue(30)='Tue';
   dayvalue(31)='Wed';
end  
if i == 10       
        for n = 1: 31
           datevalue(n) =n;
        end
   dayvalue(1)='Sat';
   dayvalue(2)='Sun';
   dayvalue(3)='Mon';
   dayvalue(4)='Tue';
   dayvalue(5)='Wed';
   dayvalue(6)='Thu';
   dayvalue(7)= 'Fri';
   dayvalue(8)='Sat';
   dayvalue(9)='Sun';
   dayvalue(10)='Mon';
   dayvalue(11)='Tue';
   dayvalue(12)='Wed';
   dayvalue(13)='Thu';
   dayvalue(14)='Fri';
   dayvalue(15)='Sat';
   dayvalue(16)='Sun';
   dayvalue(17)='Mon';
   dayvalue(18)='Tue';
   dayvalue(19)='Wed';
   dayvalue(20)='Thu';
   dayvalue(21)='Fri';
   dayvalue(22)='Sat';
   dayvalue(23)='Sun';
   dayvalue(24)='Mon';
   dayvalue(25)='Tue';
   dayvalue(26)='Wed';
   dayvalue(27)='Thu';
   dayvalue(28)='Fri';
   dayvalue(29)='Sat';
   dayvalue(30)='Sun';
   dayvalue(31)='Mon';
end 
if i == 12      
        for n = 1: 31
           datevalue(n) =n;
        end
   dayvalue(1)='Thu';
   dayvalue(2)='Fri';
   dayvalue(3)='Sat';
   dayvalue(4)='Sun';
   dayvalue(5)='Mon';
   dayvalue(6)='Tue';
   dayvalue(7)='Wed';
   dayvalue(8)='Thu';
   dayvalue(9)= 'Fri';
   dayvalue(10)='Sat';
   dayvalue(11)='Sun';
   dayvalue(12)='Mon';
   dayvalue(13)='Tue';
   dayvalue(14)='Wed';
   dayvalue(15)='Thu';
   dayvalue(16)='Fri';
   dayvalue(17)='Sat';
   dayvalue(18)='Sun';
   dayvalue(19)='Mon';
   dayvalue(20)='Tue';
   dayvalue(21)='Wed';
   dayvalue(22)='Thu';
   dayvalue(23)='Fri';
   dayvalue(24)='Sat';
   dayvalue(25)='Sun';
   dayvalue(26)='Mon';
   dayvalue(27)='Tue';
   dayvalue(28)='Wed';
   dayvalue(29)='Thu';
   dayvalue(30)='Fri';
   dayvalue(31)='Sat';

Cancel end struct S(month, monthvalue, date,datevalue, day,dayvalue);

end

[Geoff Hayes]

That's a lot of code and a lot more than necessary for this homework assignment. Start with a simple example starting with January. All you should need is to know how many days there are in each month (for 2016) and which day was January 1rst, 2016 (it was a Friday).

As for your error, put a breakpoint at the line that is throwing the error and then run your code. When the debugger pauses at this line, what can you say about dayvalue? Does your assignment make sense given how it has been initialized? Look closely at the line

 dayvalue=(31);

What does this mean to you? All that you are doing is assigning 31 to this variable. I suspect that you are trying to create an array of 31 elements but this is not the way to do so. If you know how many days are in the month, then initialize your structure array as

 numDaysInMonth = 31;
 S(numDaysInMonth) = struct('month','','date',0,'day','');

Now iterate over each element in the array and update the month, date, and day fields.

[DJ V]

I don't understand what you mean by stopping the code at the line where it faces the error. All I get out of that is an error message. I've altered my code to conform to your instructions, but somehow it still isn't working.It takes the code for the date(n) as a number, but it won't take a string when it corresponds to a date.

[Geoff Hayes]

Ummm...did we just do DJ's homework (again)?

[Stephen23]

@DJ V: you need to learn how to debug code. Start here:

https://www.mathworks.com/help/matlab/debugging-code.html

and also read this:

https://www.mathworks.com/matlabcentral/answers/228557-experts-of-matlab-how-did-you-learn-any-advice-for-beginner-intermediate-users

[Lauren Jablonowski]

I'm having an issue where I'm getting an error message when the tested input is zero. It is supposed to return an empty struct in this case, but I cannot get an if statement to work within this construct. Thanks! My code is below:

function MDD = year2016(m)
for m = 1:12
    VN = datenum([2016,m,1]):datenum([2016,m+1,1])-1;
    DN = 1+mod(VN-3,7);
    MC = {'January';'February';'March';'April';'May';'June';'July';'August';'September';'October';'November';'December'};
    DC = {'Mon','Tue','Wed','Thu','Fri','Sat','Sun'};
    MDD = struct('day',DC(DN),'date',num2cell(1:numel(VN)));
    [MDD(:).month] = deal(MC{m});
end
for m = 0
    MDD = struct(); 
end
end

[Stephen23]

@Lauren Jablonowski: none of your for loops make any sense. Get rid of them. Use one if statement.

[Lauren Jablonowski]

@Stephen Cobeldick: thanks! with the if statement and isscalar function I was able to fully solve this.

Answer 1

[Stephen23]

Something like this:

function out = year2016(m)
VN = datenum([2016,m,1]):datenum([2016,m+1,1])-1;
DN = 1+mod(VN-3,7);
MC = {'January';'February';'March';'April';'May';'June';'July';'August';'September';'October';'November';'December'};
DC = {'Mon','Tue','Wed','Thu','Fri','Sat','Sun'};
out = struct('day',DC(DN),'date',num2cell(1:numel(VN)));
[out(:).month] = deal(MC{m});
end

And tested:

>> m = year2016(12); m(8)
ans =
    day = Thu
    date =  8
    month = December
>> m = year2016(1); m(1)
ans =
    day = Fri
    date =  1
    month = January
>> m = year2016(2); m(29)
ans =
    day = Mon
    date =  29
    month = February

[DJ V]

I don't see how this will make the days of the month correspond to the dates.

[Stephen23]

@DJ V: I used datenum and colon notation to generate a vector of all serial date numbers for the selected month. Then mod to determine the day of the week as an index from 1 to 7. The day field is generated using this index to select the day of the week from a cell array of strings. The date field is generated by simply generating a vector of numbers from 1 to the length of the day field. The month field is simply filled in by using the input month to select the month string from a cell array of strings.

Here are the first two critical lines:

>> m = 2; % feb
>> VN = datenum([2016,m,1]):datenum([2016,m+1,1])-1
VN =
   736361   736362   736363   736364   736365   736366   736367   736368   736369   736370   736371   736372   736373   736374   736375   736376   736377   736378   736379   736380   736381   736382   736383   736384   736385   736386   736387   736388   736389
>> DN = 1+mod(VN-3,7)
DN =
   1   2   3   4   5   6   7   1   2   3   4   5   6   7   1   2   3   4   5   6   7   1   2   3   4   5   6   7   1

DN is a vector of all days of the week for the month. Check it yourself if you do not believe me (Hint: the first and last days of February 2016 were both Mondays, which is what my code shows above). This vector DN is simply used as an index to give the days corresponding to the dates, exactly as requested. The dates is a simple vector from 1 to numel(..) because where I come from the first day of the month is the 1st.

"I don't see how this will make the days of the month correspond to the dates"

That is okay. Use MATLAB's documentation to help you understand how the functions I used work. Try them out yourself: play around with them, try different values. When you do this you might learn some much better ways to write code than relying on if's and copy-and-pasting hundreds of lines of text.

[DJ V]

It works, thanks!

Answer 2

[Geoff Hayes]

DJ - the function returns an array of structs where each element corresponds to a day of the month. So if the user passes in an integer that is outside of the interval [1,12], then an empty array is returned. If the integer is within this interval, then the array has that many structs as days in the month. For example, if 1 is the passed in integer, then the output is an array of 31 elements where m(1) corresponds to January 1rst, m(2) corresponds to January 2nd, etc.

[DJ V]

Thanks, I read it over again and saw that.

Answer 3

[Walter Roberson]

Your code uses (for example)

      for n = 1 :31
           datevalue(n) =n;
           monthvalue(n)='August';
        end

assigns numeric values to datevalue, so datevalue(1) is a numeric scalar.

Then after that you

   dayvalue(1)='Mon';

or similar. That attempts to assign the 3-element character vector ['M', 'o', 'n'] to the single numeric scalar position dayvalue(1)

In order to be able to make the assignment

     dayvalue(1)='Mon';

you would need to modify your initialization loop to

      for n = 1 :31
           datevalue(n) = strings(1);
           monthvalue(n)='August';
        end

(there are other better ways, but this is the minimum change.)

You will need to be using R2016b to do this. If you are using any earlier release then it is not possible to do

   dayvalue(1)='Mon';

and you would need to switch to cell arrays such as

   dayvalue{1}='Mon';

after having change the initialization to

      for n = 1 :31
           datevalue(n) = cell(1);
           monthvalue(n)='August';
        end

(again, there are better ways.)

[DJ V]

believe there is an error in your code, you are assigning datevalue(n) to strings, but I want to assign dayvalue(n) to strings.

[DJ V]

Okay, it runs, but I'm getting empty array elements back rather than array elements filled with data when I enter m(7), this is with:

if i == 1    
        numDaysInMonth = 31;
        S(numDaysInMonth) = struct('month','January','date',0,'day','');
        for n = 1:31
           datevalue(n) =n;
           month='January';
dayvalue(n)=strings(1);
        end
   dayvalue(1)='Fri';
   dayvalue(2)='Sat';

[Walter Roberson]

You are not storing anything into m with that code. You have no variable named m anywhere in your posted code.

[DJ V]

Okay, this appears to work, but the grader software doesn't like the answer, although it appears to be correct, the only thing I notice is that the example has day: 'Sun' in single quote marks, and I have day: "Sun" in double quote marks.

and my code produced day: "Sun", which suggests I have a different type than the grader program wants.

function S = year2016( i)
%YEAR2016 Summary of this function goes here
%   Detailed explanation goes here
cest=true;
for month = 1:12
    if i == month
        cest = false;
    end
    if month ==12 && cest == true
        S = [];
        break;
    end
end

if i ==4 || i == 9 ||i == 11 || i ==6 || i == 2
   if i ==4
        monthval = 'April';
        daycount = 30;
       for n = 1:30
           datevalue(n) =n;
           dayvalue(n)=strings(1);
        end
   dayvalue(1)='Fri';
   dayvalue(2)='Sat';
   dayvalue(3)='Sun';
   dayvalue(4)='Mon';
   dayvalue(5)='Tue';
   dayvalue(6)='Wed';
   dayvalue(7)='Thu';
   dayvalue(8)='Fri';
   dayvalue(9)='Sat';
   dayvalue(10)='Sun';
   dayvalue(11)='Mon';
   dayvalue(12)='Tue';
   dayvalue(13)='Wed';
   dayvalue(14)='Thu';
   dayvalue(15)= 'Fri';
   dayvalue(16)='Sat';
   dayvalue(17)='Sun';
   dayvalue(18)='Mon';
   dayvalue(19)='Tue';
   dayvalue(20)='Wed';
   dayvalue(21)='Thu';
   dayvalue(22)='Fri';
   dayvalue(23)='Sat';
   dayvalue(24)='Sun';
   dayvalue(25)='Mon';
   dayvalue(26)='Tue';
   dayvalue(27)='Wed';
   dayvalue(28)='Thu';
   dayvalue(29)='Fri';
   dayvalue(30)='Sat';
end
   if i == 6
       monthval = 'June';
        daycount = 30;
       for n = 1:30
           datevalue(n) =n;
           dayvalue(n)=strings(1);
        end
   dayvalue(1)='Wed';
   dayvalue(2)='Thu';
   dayvalue(3)='Fri';
   dayvalue(4)='Sat';
   dayvalue(5)='Sun';
   dayvalue(6)='Mon';
   dayvalue(7)='Tue';
   dayvalue(8)='Wed';
   dayvalue(9)='Thu';
   dayvalue(10)= 'Fri';
   dayvalue(11)='Sat';
   dayvalue(12)='Sun';
   dayvalue(13)='Mon';
   dayvalue(14)='Tue';
   dayvalue(15)='Wed';
   dayvalue(16)='Thu';
   dayvalue(17)='Fri';
   dayvalue(18)='Sat';
   dayvalue(19)='Sun';
   dayvalue(20)='Mon';
   dayvalue(21)='Tue';
   dayvalue(22)='Wed';
   dayvalue(23)='Thu';
   dayvalue(24)='Fri';
   dayvalue(25)='Sat';
   dayvalue(26)='Sun';
   dayvalue(27)='Mon';
   dayvalue(28)='Tue';
   dayvalue(29)='Wed';
   dayvalue(30)='Thu';
   end
   if i == 9
       monthval = 'September';
        daycount = 30;
       for n = 1:30
           datevalue(n) =n;
           dayvalue(n)=strings(1);
        end
   dayvalue(1)='Thu';
   dayvalue(2)='Fri';
   dayvalue(3)='Sat';
   dayvalue(4)='Sun';
   dayvalue(5)='Mon';
   dayvalue(6)='Tue';
   dayvalue(7)='Wed';
   dayvalue(8)='Thu';
   dayvalue(9)= 'Fri';
   dayvalue(10)='Sat';
   dayvalue(11)='Sun';
   dayvalue(12)='Mon';
   dayvalue(13)='Tue';
   dayvalue(14)='Wed';
   dayvalue(15)='Thu';
   dayvalue(16)='Fri';
   dayvalue(17)='Sat';
   dayvalue(18)='Sun';
   dayvalue(19)='Mon';
   dayvalue(20)='Tue';
   dayvalue(21)='Wed';
   dayvalue(22)='Thu';
   dayvalue(23)='Fri';
   dayvalue(24)='Sat';
   dayvalue(25)='Sun';
   dayvalue(26)='Mon';
   dayvalue(27)='Tue';
   dayvalue(28)='Wed';
   dayvalue(29)='Thu';
   dayvalue(30)='Fri';
end
   if i == 11
        monthval = 'November';
        daycount = 30;
       for n = 1:30
           datevalue(n) =n;
           dayvalue(n)=strings(1);
        end
   dayvalue(1)='Tue';
   dayvalue(2)='Wed';
   dayvalue(3)='Thu';
   dayvalue(4)='Fri';
   dayvalue(5)='Sat';
   dayvalue(6)='Sun';
   dayvalue(7)='Mon';
   dayvalue(8)='Tue';
   dayvalue(9)='Wed';
   dayvalue(10)='Thu';
   dayvalue(11)= 'Fri';
   dayvalue(12)='Sat';
   dayvalue(13)='Sun';
   dayvalue(14)='Mon';
   dayvalue(15)='Tue';
   dayvalue(16)='Wed';
   dayvalue(17)='Thu';
   dayvalue(18)='Fri';
   dayvalue(19)='Sat';
   dayvalue(20)='Sun';
   dayvalue(21)='Mon';
   dayvalue(22)='Tue';
   dayvalue(23)='Wed';
   dayvalue(24)='Thu';
   dayvalue(25)='Fri';
   dayvalue(26)='Sat';
   dayvalue(27)='Sun';
   dayvalue(28)='Mon';
   dayvalue(29)='Tue';
   dayvalue(30)='Wed';
   end
if i ==2
        monthval = 'February';
        daycount = 29;
       for n = 1:29
           datevalue(n) =n;
           dayvalue(n)=strings(1);
        end
   dayvalue(1)='Mon';
   dayvalue(2)='Tue';
   dayvalue(3)='Wed';
   dayvalue(4)='Thu';
   dayvalue(5)='Fri';
   dayvalue(6)='Sat';
   dayvalue(7)='Sun';
   dayvalue(8)='Mon';
   dayvalue(9)='Tue';
   dayvalue(10)='Wed';
   dayvalue(11)='Thu';
   dayvalue(12)='Fri';
   dayvalue(13)='Sat';
   dayvalue(14)='Sun';
   dayvalue(15)='Mon';
   dayvalue(16)='Tue';
   dayvalue(17)='Wed';
   dayvalue(18)='Thu';
   dayvalue(19)='Fri';
   dayvalue(20)='Sat';
   dayvalue(21)='Sun';
   dayvalue(22)='Mon';
   dayvalue(23)='Tue';
   dayvalue(24)='Wed';
   dayvalue(25)='Thu';
   dayvalue(26)='Fri';
   dayvalue(27)='Sat';
   dayvalue(28)='Sun';
   dayvalue(29)='Mon';
end
for n =1:daycount
        S(n) = struct('month',monthval,'date',datevalue(n),'day',dayvalue(n));
end
return;
end
if i==1||i ==3||i==5||i == 7||i==8||i ==10||i ==12
if i == 1    
        monthval = 'January';
        daycount = 31;
       for n = 1:31
           datevalue(n) =n;
           dayvalue(n)=strings(1);
        end
   dayvalue(1)='Fri';
   dayvalue(2)='Sat';
   dayvalue(3)='Sun';
   dayvalue(4)='Mon';
   dayvalue(5)='Tue';
   dayvalue(6)='Wed';
   dayvalue(7)='Thu';
   dayvalue(8)='Fri';
   dayvalue(9)='Sat';
   dayvalue(10)='Sun';
   dayvalue(11)='Mon';
   dayvalue(12)='Tue';
   dayvalue(13)='Wed';
   dayvalue(14)='Thu';
   dayvalue(15)= 'Fri';
   dayvalue(16)='Sat';
   dayvalue(17)='Sun';
   dayvalue(18)='Mon';
   dayvalue(19)='Tue';
   dayvalue(20)='Wed';
   dayvalue(21)='Thu';
   dayvalue(22)='Fri';
   dayvalue(23)='Sat';
   dayvalue(24)='Sun';
   dayvalue(25)='Mon';
   dayvalue(26)='Tue';
   dayvalue(27)='Wed';
   dayvalue(28)='Thu';
   dayvalue(29)='Fri';
   dayvalue(30)='Sat';
   dayvalue(31)='Sun';
end
if i == 3  
       monthval = 'March';
       daycount = 31;
       for n = 1:31
           datevalue(n) =n;
           dayvalue(n)=strings(1);
        end
   dayvalue(1)='Tue';
   dayvalue(2)='Wed';
   dayvalue(3)='Thu';
   dayvalue(4)='Fri';
   dayvalue(5)='Sat';
   dayvalue(6)='Sun';
   dayvalue(7)='Mon';
   dayvalue(8)='Tue';
   dayvalue(9)='Wed';
   dayvalue(10)='Thu';
   dayvalue(11)= 'Fri';
   dayvalue(12)='Sat';
   dayvalue(13)='Sun';
   dayvalue(14)='Mon';
   dayvalue(15)='Tue';
   dayvalue(16)='Wed';
   dayvalue(17)='Thu';
   dayvalue(18)='Fri';
   dayvalue(19)='Sat';
   dayvalue(20)='Sun';
   dayvalue(21)='Mon';
   dayvalue(22)='Tue';
   dayvalue(23)='Wed';
   dayvalue(24)='Thu';
   dayvalue(25)='Fri';
   dayvalue(26)='Sat';
   dayvalue(27)='Sun';
   dayvalue(28)='Mon';
   dayvalue(29)='Tue';
   dayvalue(30)='Wed';
   dayvalue(31)='Thu';
end  
if i == 5  
       monthval = 'May';
       daycount = 31;
       for n = 1:31
           datevalue(n) =n;
           dayvalue(n)=strings(1);
        end
   dayvalue(1)='Sun';
   dayvalue(2)='Mon';
   dayvalue(3)='Tue';
   dayvalue(4)='Wed';
   dayvalue(5)='Thu';
   dayvalue(6)= 'Fri';
   dayvalue(7)='Sat';
   dayvalue(8)='Sun';
   dayvalue(9)='Mon';
   dayvalue(10)='Tue';
   dayvalue(11)='Wed';
   dayvalue(12)='Thu';
   dayvalue(13)='Fri';
   dayvalue(14)='Sat';
   dayvalue(15)='Sun';
   dayvalue(16)='Mon';
   dayvalue(17)='Tue';
   dayvalue(18)='Wed';
   dayvalue(19)='Thu';
   dayvalue(20)='Fri';
   dayvalue(21)='Sat';
   dayvalue(22)='Sun';
   dayvalue(23)='Mon';
   dayvalue(24)='Tue';
   dayvalue(25)='Wed';
   dayvalue(26)='Thu';
   dayvalue(27)='Fri';
   dayvalue(28)='Sat';
   dayvalue(29)='Sun';
   dayvalue(30)='Mon';
   dayvalue(31)='Tue';
end    
if i == 7  
        monthval = 'July';
        daycount = 31;
       for n = 1:31
           datevalue(n) =n;
           dayvalue(n)=strings(1);
        end
   dayvalue(1)='Fri';
   dayvalue(2)='Sat';
   dayvalue(3)='Sun';
   dayvelue(4)='Mon';
   dayvalue(5)='Tue';
   dayvalue(6)='Wed';
   dayvalue(7)='Thu';
   dayvalue(8)='Fri';
   dayvalue(9)='Sat';
   dayvalue(10)='Sun';
   dayvalue(11)='Mon';
   dayvalue(12)='Tue';
   dayvalue(13)='Wed';
   dayvalue(14)='Thu';
   dayvalue(15)= 'Fri';
   dayvalue(16)='Sat';
   dayvalue(17)='Sun';
   dayvalue(18)='Mon';
   dayvalue(19)='Tue';
   dayvalue(20)='Wed';
   dayvalue(21)='Thu';
   dayvalue(22)='Fri';
   dayvalue(23)='Sat';
   dayvalue(24)='Sun';
   dayvalue(25)='Mon';
   dayvalue(26)='Tue';
   dayvalue(27)='Wed';
   dayvalue(28)='Thu';
   dayvalue(29)='Fri';
   dayvalue(30)='Sat';
   dayvalue(31)='Sun';
end     
if i == 8    
         monthval = 'August';
        daycount = 31;
       for n = 1:31
           datevalue(n) =n;
           dayvalue(n)=strings(1);
        end
   dayvalue(1)='Mon';
   dayvalue(2)='Tue';
   dayvalue(3)='Wed';
   dayvalue(4)='Thu';
   dayvalue(5)='Fri';
   dayvalue(6)='Sat';
   dayvalue(7)='Sun';
   dayvalue(8)='Mon';
   dayvalue(9)='Tue';
   dayvalue(10)='Wed';
   dayvalue(11)='Thu';
   dayvalue(12)='Fri';
   dayvalue(13)='Sat';
   dayvalue(14)='Sun';
   dayvalue(15)='Mon';
   dayvalue(16)='Tue';
   dayvalue(17)='Wed';
   dayvalue(18)='Thu';
   dayvalue(19)='Fri';
   dayvalue(20)='Sat';
   dayvalue(21)='Sun';
   dayvalue(22)='Mon';
   dayvalue(23)='Tue';
   dayvalue(24)='Wed';
   dayvalue(25)='Thu';
   dayvalue(26)='Fri';
   dayvalue(27)='Sat';
   dayvalue(28)='Sun';
   dayvalue(29)='Mon';
   dayvalue(30)='Tue';
   dayvalue(31)='Wed';
end  
if i == 10     
         monthval = 'October';
        daycount = 31;
       for n = 1:31
           datevalue(n) =n;
           dayvalue(n)=strings(1);
        end
        end
   dayvalue(1)='Sat';
   dayvalue(2)='Sun';
   dayvalue(3)='Mon';
   dayvalue(4)='Tue';
   dayvalue(5)='Wed';
   dayvalue(6)='Thu';
   dayvalue(7)= 'Fri';
   dayvalue(8)='Sat';
   dayvalue(9)='Sun';
   dayvalue(10)='Mon';
   dayvalue(11)='Tue';
   dayvalue(12)='Wed';
   dayvalue(13)='Thu';
   dayvalue(14)='Fri';
   dayvalue(15)='Sat';
   dayvalue(16)='Sun';
   dayvalue(17)='Mon';
   dayvalue(18)='Tue';
   dayvalue(19)='Wed';
   dayvalue(20)='Thu';
   dayvalue(21)='Fri';
   dayvalue(22)='Sat';
   dayvalue(23)='Sun';
   dayvalue(24)='Mon';
   dayvalue(25)='Tue';
   dayvalue(26)='Wed';
   dayvalue(27)='Thu';
   dayvalue(28)='Fri';
   dayvalue(29)='Sat';
   dayvalue(30)='Sun';
   dayvalue(31)='Mon';
end 
if i == 12 
         monthval = 'December';
        daycount = 31;
       for n = 1:31
           datevalue(n) =n;
           dayvalue(n)=strings(1);
        end
   dayvalue(1)='Thu';
   dayvalue(2)='Fri';
   dayvalue(3)='Sat';
   dayvalue(4)='Sun';
   dayvalue(5)='Mon';
   dayvalue(6)='Tue';
   dayvalue(7)='Wed';
   dayvalue(8)='Thu';
   dayvalue(9)= 'Fri';
   dayvalue(10)='Sat';
   dayvalue(11)='Sun';
   dayvalue(12)='Mon';
   dayvalue(13)='Tue';
   dayvalue(14)='Wed';
   dayvalue(15)='Thu';
   dayvalue(16)='Fri';
   dayvalue(17)='Sat';
   dayvalue(18)='Sun';
   dayvalue(19)='Mon';
   dayvalue(20)='Tue';
   dayvalue(21)='Wed';
   dayvalue(22)='Thu';
   dayvalue(23)='Fri';
   dayvalue(24)='Sat';
   dayvalue(25)='Sun';
   dayvalue(26)='Mon';
   dayvalue(27)='Tue';
   dayvalue(28)='Wed';
   dayvalue(29)='Thu';
   dayvalue(30)='Fri';
   dayvalue(31)='Sat';
end 

          for n =1:daycount
          S(n) = struct('month',monthval,'date',datevalue(n),'day',dayvalue(n));
          end
  end

[DJ V]

Okay, what follows works. It isn't graded as right by the software, but it does what its supposed to do. I think the problem is the string declaration instead of using an array of chars for the three letter day of week abbreviations. Any idea how to do that with chars instead of a string?

function S = year2016(i)
%YEAR2016 Summary of this function goes here
%   Detailed explanation goes here
cest=true;
for month = 1:12
    if i == month
        cest = false;
    end
    if month ==12 && cest == true
        S = [];
        break;
    end
end

if i ==4 || i == 9 ||i == 11 || i ==6 || i == 2
   if i ==4
        monthval = 'April';
        daycount = 30;
       for n = 1:30
           datevalue(n) =n;
           dayvalue(n)=strings(1);
        end
   dayvalue(1)='Fri';
   dayvalue(2)='Sat';
   dayvalue(3)='Sun';
   dayvalue(4)='Mon';
   dayvalue(5)='Tue';
   dayvalue(6)='Wed';
   dayvalue(7)='Thu';
   dayvalue(8)='Fri';
   dayvalue(9)='Sat';
   dayvalue(10)='Sun';
   dayvalue(11)='Mon';
   dayvalue(12)='Tue';
   dayvalue(13)='Wed';
   dayvalue(14)='Thu';
   dayvalue(15)= 'Fri';
   dayvalue(16)='Sat';
   dayvalue(17)='Sun';
   dayvalue(18)='Mon';
   dayvalue(19)='Tue';
   dayvalue(20)='Wed';
   dayvalue(21)='Thu';
   dayvalue(22)='Fri';
   dayvalue(23)='Sat';
   dayvalue(24)='Sun';
   dayvalue(25)='Mon';
   dayvalue(26)='Tue';
   dayvalue(27)='Wed';
   dayvalue(28)='Thu';
   dayvalue(29)='Fri';
   dayvalue(30)='Sat';
end
   if i == 6
       monthval = 'June';
        daycount = 30;
       for n = 1:30
           datevalue(n) =n;
           dayvalue(n)=strings(1);
        end
   dayvalue(1)='Wed';
   dayvalue(2)='Thu';
   dayvalue(3)='Fri';
   dayvalue(4)='Sat';
   dayvalue(5)='Sun';
   dayvalue(6)='Mon';
   dayvalue(7)='Tue';
   dayvalue(8)='Wed';
   dayvalue(9)='Thu';
   dayvalue(10)= 'Fri';
   dayvalue(11)='Sat';
   dayvalue(12)='Sun';
   dayvalue(13)='Mon';
   dayvalue(14)='Tue';
   dayvalue(15)='Wed';
   dayvalue(16)='Thu';
   dayvalue(17)='Fri';
   dayvalue(18)='Sat';
   dayvalue(19)='Sun';
   dayvalue(20)='Mon';
   dayvalue(21)='Tue';
   dayvalue(22)='Wed';
   dayvalue(23)='Thu';
   dayvalue(24)='Fri';
   dayvalue(25)='Sat';
   dayvalue(26)='Sun';
   dayvalue(27)='Mon';
   dayvalue(28)='Tue';
   dayvalue(29)='Wed';
   dayvalue(30)='Thu';
   end
   if i == 9
       monthval = 'September';
        daycount = 30;
       for n = 1:30
           datevalue(n) =n;
           dayvalue(n)=strings(1);
        end
   dayvalue(1)='Thu';
   dayvalue(2)='Fri';
   dayvalue(3)='Sat';
   dayvalue(4)='Sun';
   dayvalue(5)='Mon';
   dayvalue(6)='Tue';
   dayvalue(7)='Wed';
   dayvalue(8)='Thu';
   dayvalue(9)= 'Fri';
   dayvalue(10)='Sat';
   dayvalue(11)='Sun';
   dayvalue(12)='Mon';
   dayvalue(13)='Tue';
   dayvalue(14)='Wed';
   dayvalue(15)='Thu';
   dayvalue(16)='Fri';
   dayvalue(17)='Sat';
   dayvalue(18)='Sun';
   dayvalue(19)='Mon';
   dayvalue(20)='Tue';
   dayvalue(21)='Wed';
   dayvalue(22)='Thu';
   dayvalue(23)='Fri';
   dayvalue(24)='Sat';
   dayvalue(25)='Sun';
   dayvalue(26)='Mon';
   dayvalue(27)='Tue';
   dayvalue(28)='Wed';
   dayvalue(29)='Thu';
   dayvalue(30)='Fri';
end
   if i == 11
        monthval = 'November';
        daycount = 30;
       for n = 1:30
           datevalue(n) =n;
           dayvalue(n)=strings(1);
        end
   dayvalue(1)='Tue';
   dayvalue(2)='Wed';
   dayvalue(3)='Thu';
   dayvalue(4)='Fri';
   dayvalue(5)='Sat';
   dayvalue(6)='Sun';
   dayvalue(7)='Mon';
   dayvalue(8)='Tue';
   dayvalue(9)='Wed';
   dayvalue(10)='Thu';
   dayvalue(11)= 'Fri';
   dayvalue(12)='Sat';
   dayvalue(13)='Sun';
   dayvalue(14)='Mon';
   dayvalue(15)='Tue';
   dayvalue(16)='Wed';
   dayvalue(17)='Thu';
   dayvalue(18)='Fri';
   dayvalue(19)='Sat';
   dayvalue(20)='Sun';
   dayvalue(21)='Mon';
   dayvalue(22)='Tue';
   dayvalue(23)='Wed';
   dayvalue(24)='Thu';
   dayvalue(25)='Fri';
   dayvalue(26)='Sat';
   dayvalue(27)='Sun';
   dayvalue(28)='Mon';
   dayvalue(29)='Tue';
   dayvalue(30)='Wed';
   end
if i ==2
        monthval = 'February';
        daycount = 29;
        dayvalue(1:29)= string(1);
       for n = 1:29
           datevalue(n) =n;
        end
   dayvalue(1)='Mon';
   dayvalue(2)='Tue';
   dayvalue(3)='Wed';
   dayvalue(4)='Thu';
   dayvalue(5)='Fri';
   dayvalue(6)='Sat';
   dayvalue(7)='Sun';
   dayvalue(8)='Mon';
   dayvalue(9)='Tue';
   dayvalue(10)='Wed';
   dayvalue(11)='Thu';
   dayvalue(12)='Fri';
   dayvalue(13)='Sat';
   dayvalue(14)='Sun';
   dayvalue(15)='Mon';
   dayvalue(16)='Tue';
   dayvalue(17)='Wed';
   dayvalue(18)='Thu';
   dayvalue(19)='Fri';
   dayvalue(20)='Sat';
   dayvalue(21)='Sun';
   dayvalue(22)='Mon';
   dayvalue(23)='Tue';
   dayvalue(24)='Wed';
   dayvalue(25)='Thu';
   dayvalue(26)='Fri';
   dayvalue(27)='Sat';
   dayvalue(28)='Sun';
   dayvalue(29)='Mon';
end
for n =1:daycount
        S(n) = struct('month',monthval,'date',datevalue(n),'day',dayvalue(n));
end
return;
end
if i==1||i ==3||i==5||i == 7||i==8||i ==10||i ==12
if i == 1    
        monthval = 'January';
        daycount = 31;
       for n = 1:31
           datevalue(n) =n;
           dayvalue(n)=strings(1);
        end
   dayvalue(1)='Fri';
   dayvalue(2)='Sat';
   dayvalue(3)='Sun';
   dayvalue(4)='Mon';
   dayvalue(5)='Tue';
   dayvalue(6)='Wed';
   dayvalue(7)='Thu';
   dayvalue(8)='Fri';
   dayvalue(9)='Sat';
   dayvalue(10)='Sun';
   dayvalue(11)='Mon';
   dayvalue(12)='Tue';
   dayvalue(13)='Wed';
   dayvalue(14)='Thu';
   dayvalue(15)= 'Fri';
   dayvalue(16)='Sat';
   dayvalue(17)='Sun';
   dayvalue(18)='Mon';
   dayvalue(19)='Tue';
   dayvalue(20)='Wed';
   dayvalue(21)='Thu';
   dayvalue(22)='Fri';
   dayvalue(23)='Sat';
   dayvalue(24)='Sun';
   dayvalue(25)='Mon';
   dayvalue(26)='Tue';
   dayvalue(27)='Wed';
   dayvalue(28)='Thu';
   dayvalue(29)='Fri';
   dayvalue(30)='Sat';
   dayvalue(31)='Sun';
end
if i == 3  
       monthval = 'March';
       daycount = 31;
       for n = 1:31
           datevalue(n) =n;
           dayvalue(n)=strings(1);
        end
   dayvalue(1)='Tue';
   dayvalue(2)='Wed';
   dayvalue(3)='Thu';
   dayvalue(4)='Fri';
   dayvalue(5)='Sat';
   dayvalue(6)='Sun';
   dayvalue(7)='Mon';
   dayvalue(8)='Tue';
   dayvalue(9)='Wed';
   dayvalue(10)='Thu';
   dayvalue(11)= 'Fri';
   dayvalue(12)='Sat';
   dayvalue(13)='Sun';
   dayvalue(14)='Mon';
   dayvalue(15)='Tue';
   dayvalue(16)='Wed';
   dayvalue(17)='Thu';
   dayvalue(18)='Fri';
   dayvalue(19)='Sat';
   dayvalue(20)='Sun';
   dayvalue(21)='Mon';
   dayvalue(22)='Tue';
   dayvalue(23)='Wed';
   dayvalue(24)='Thu';
   dayvalue(25)='Fri';
   dayvalue(26)='Sat';
   dayvalue(27)='Sun';
   dayvalue(28)='Mon';
   dayvalue(29)='Tue';
   dayvalue(30)='Wed';
   dayvalue(31)='Thu';
end  
if i == 5  
       monthval = 'May';
       daycount = 31;
       for n = 1:31
           datevalue(n) =n;
           dayvalue(n)=strings(1);
        end
   dayvalue(1)='Sun';
   dayvalue(2)='Mon';
   dayvalue(3)='Tue';
   dayvalue(4)='Wed';
   dayvalue(5)='Thu';
   dayvalue(6)= 'Fri';
   dayvalue(7)='Sat';
   dayvalue(8)='Sun';
   dayvalue(9)='Mon';
   dayvalue(10)='Tue';
   dayvalue(11)='Wed';
   dayvalue(12)='Thu';
   dayvalue(13)='Fri';
   dayvalue(14)='Sat';
   dayvalue(15)='Sun';
   dayvalue(16)='Mon';
   dayvalue(17)='Tue';
   dayvalue(18)='Wed';
   dayvalue(19)='Thu';
   dayvalue(20)='Fri';
   dayvalue(21)='Sat';
   dayvalue(22)='Sun';
   dayvalue(23)='Mon';
   dayvalue(24)='Tue';
   dayvalue(25)='Wed';
   dayvalue(26)='Thu';
   dayvalue(27)='Fri';
   dayvalue(28)='Sat';
   dayvalue(29)='Sun';
   dayvalue(30)='Mon';
   dayvalue(31)='Tue';
end    
if i == 7  
        monthval = 'July';
        daycount = 31;
       for n = 1:31
           datevalue(n) =n;
           dayvalue(n)=strings(1);
        end
   dayvalue(1)='Fri';
   dayvalue(2)='Sat';
   dayvalue(3)='Sun';
   dayvalue(4)='Mon';
   dayvalue(5)='Tue';
   dayvalue(6)='Wed';
   dayvalue(7)='Thu';
   dayvalue(8)='Fri';
   dayvalue(9)='Sat';
   dayvalue(10)='Sun';
   dayvalue(11)='Mon';
   dayvalue(12)='Tue';
   dayvalue(13)='Wed';
   dayvalue(14)='Thu';
   dayvalue(15)= 'Fri';
   dayvalue(16)='Sat';
   dayvalue(17)='Sun';
   dayvalue(18)='Mon';
   dayvalue(19)='Tue';
   dayvalue(20)='Wed';
   dayvalue(21)='Thu';
   dayvalue(22)='Fri';
   dayvalue(23)='Sat';
   dayvalue(24)='Sun';
   dayvalue(25)='Mon';
   dayvalue(26)='Tue';
   dayvalue(27)='Wed';
   dayvalue(28)='Thu';
   dayvalue(29)='Fri';
   dayvalue(30)='Sat';
   dayvalue(31)='Sun';
end     
if i == 8    
         monthval = 'August';
        daycount = 31;
       for n = 1:31
           datevalue(n) =n;
           dayvalue(n)=strings(1);
        end
   dayvalue(1)='Mon';
   dayvalue(2)='Tue';
   dayvalue(3)='Wed';
   dayvalue(4)='Thu';
   dayvalue(5)='Fri';
   dayvalue(6)='Sat';
   dayvalue(7)='Sun';
   dayvalue(8)='Mon';
   dayvalue(9)='Tue';
   dayvalue(10)='Wed';
   dayvalue(11)='Thu';
   dayvalue(12)='Fri';
   dayvalue(13)='Sat';
   dayvalue(14)='Sun';
   dayvalue(15)='Mon';
   dayvalue(16)='Tue';
   dayvalue(17)='Wed';
   dayvalue(18)='Thu';
   dayvalue(19)='Fri';
   dayvalue(20)='Sat';
   dayvalue(21)='Sun';
   dayvalue(22)='Mon';
   dayvalue(23)='Tue';
   dayvalue(24)='Wed';
   dayvalue(25)='Thu';
   dayvalue(26)='Fri';
   dayvalue(27)='Sat';
   dayvalue(28)='Sun';
   dayvalue(29)='Mon';
   dayvalue(30)='Tue';
   dayvalue(31)='Wed';
end  
if i == 10     
         monthval = 'October';
        daycount = 31;
       for n = 1:31
           datevalue(n) =n;
           dayvalue(n)=strings(1);
       end
   dayvalue(1)='Sat';
   dayvalue(2)='Sun';
   dayvalue(3)='Mon';
   dayvalue(4)='Tue';
   dayvalue(5)='Wed';
   dayvalue(6)='Thu';
   dayvalue(7)= 'Fri';
   dayvalue(8)='Sat';
   dayvalue(9)='Sun';
   dayvalue(10)='Mon';
   dayvalue(11)='Tue';
   dayvalue(12)='Wed';
   dayvalue(13)='Thu';
   dayvalue(14)='Fri';
   dayvalue(15)='Sat';
   dayvalue(16)='Sun';
   dayvalue(17)='Mon';
   dayvalue(18)='Tue';
   dayvalue(19)='Wed';
   dayvalue(20)='Thu';
   dayvalue(21)='Fri';
   dayvalue(22)='Sat';
   dayvalue(23)='Sun';
   dayvalue(24)='Mon';
   dayvalue(25)='Tue';
   dayvalue(26)='Wed';
   dayvalue(27)='Thu';
   dayvalue(28)='Fri';
   dayvalue(29)='Sat';
   dayvalue(30)='Sun';
   dayvalue(31)='Mon';
end 
if i == 12 
         monthval = 'December';
        daycount = 31;
       for n = 1:31
           datevalue(n) =n;
           dayvalue(n)=strings(1);
        end
   dayvalue(1)='Thu';
   dayvalue(2)='Fri';
   dayvalue(3)='Sat';
   dayvalue(4)='Sun';
   dayvalue(5)='Mon';
   dayvalue(6)='Tue';
   dayvalue(7)='Wed';
   dayvalue(8)='Thu';
   dayvalue(9)= 'Fri';
   dayvalue(10)='Sat';
   dayvalue(11)='Sun';
   dayvalue(12)='Mon';
   dayvalue(13)='Tue';
   dayvalue(14)='Wed';
   dayvalue(15)='Thu';
   dayvalue(16)='Fri';
   dayvalue(17)='Sat';
   dayvalue(18)='Sun';
   dayvalue(19)='Mon';
   dayvalue(20)='Tue';
   dayvalue(21)='Wed';
   dayvalue(22)='Thu';
   dayvalue(23)='Fri';
   dayvalue(24)='Sat';
   dayvalue(25)='Sun';
   dayvalue(26)='Mon';
   dayvalue(27)='Tue';
   dayvalue(28)='Wed';
   dayvalue(29)='Thu';
   dayvalue(30)='Fri';
   dayvalue(31)='Sat';
end 

          for n =1:daycount
          S(n) = struct('month',monthval,'date',datevalue(n),'day',dayvalue(n));
          end
  end

[Walter Roberson]

See what I posted about cell arrays.

Answer 4

[Radoslav Gagov]

Here is how I dealed with the Problem:

 m = year2016(n)
    if length(n) ~= 1 || n < 1 || n >12 || n ~= round(n)
        year = []; m = year;
    else
    year = [];
     a{1} = 'Mon'; a{2} = 'Tue'; a{3} = 'Wed'; a{4} = 'Thu'; 
       a{5} = 'Fri'; a{6} = 'Sat'; a{7} = 'Sun';a{8} = 'Mon'; 
       a{9} = 'Tue'; a{10} = 'Wed'; a{11} = 'Thu';       
       a{12} = 'Fri'; a{13} = 'Sat'; a{14} = 'Sun';
    if n == 1 || n == 3 || n==5 || n==7 || n==8 || n==10 || 
                      n==12
        for i = 1 : 31             
            p = mod(i,7) ;
            if p == 0
               p = 7;
            end

            year(1).m(i).month = 'January';
            year(1).m(i).date = i;
            year(1).m(i).day = a{p+4};

            year(3).m(i).month = 'March';
            year(3).m(i).date = i;
            year(3).m(i).day = a{p+1};

            year(5).m(i).month = 'May';
            year(5).m(i).date = i;
            year(5).m(i).day = a{p+6};

            year(7).m(i).month = 'July';
            year(7).m(i).date = i;
            year(7).m(i).day = a{p+4}; 

            year(8).m(i).month = 'August';
            year(8).m(i).date = i;
            year(8).m(i).day = a{p};

            year(10).m(i).month = 'October';
            year(10).m(i).date = i;
            year(10).m(i).day = a{p+5};

            year(12).m(i).month = 'December';
            year(12).m(i).date = i;
            year(12).m(i).day = a{p+3};
        end
    end
    if n == 4 || n == 6 || n==9 || n==11
        for i = 1 : 30

            p = mod(i,7) ;
            if p == 0
               p = 7;
            end

            year(4).m(i).month = 'April';
            year(4).m(i).date = i;
            year(4).m(i).day = a{p+4};

            year(6).m(i).month = 'June';
            year(6).m(i).date = i;
            year(6).m(i).day = a{p+2};

            year(9).m(i).month = 'September';
            year(9).m(i).date = i;
            year(9).m(i).day = a{p+3};

            year(11).m(i).month = 'November';
            year(11).m(i).date = i;
            year(11).m(i).day = a{p+1};
        end
    end
    if n == 2
         for i = 1 : 29              
            p = mod(i,7) ;
            if p == 0
               p = 7;
            end           
            year(2).m(i).month = 'February';
            year(2).m(i).date = i;
            year(2).m(i).day = a{p};
         end
    end

    m = year(n).m;
    end
end

[Stephen23]

Some observations:

• This code is much more complicated than it needs to be. More code -> harder to check and more bugs.
• Do not write code that already exists and does what you need, particularly when it is tested and more optimized than what you can write yourself. The date functions datenum, etc, already convert and give the correct date/day values, so there is no point in replicating this using loops, etc.
• This code generates multiple months, even though only one of them is output. Not an efficient use of memory.
• Uses loops, and expands the structures on each loop iteration. Not an efficient use of memory.
• Uses magic numbers (these are the days per month): code should not use magic numbers without adequate explanation.
• Defines a in a very strange way. Much simpler: a = {'Mon','Tue',...}.
• Uses more than fourteen times as many lines of code as my answer.
• Is nearly thirty times slower than my answer (1000 repetitions):

Elapsed time is 1.26207 seconds. % my answer
Elapsed time is 34.606 seconds.  % this answer

Hopefully other beginners will not use this as an example to learn MATLAB from.