Extract Values from matrix and use them to calculate days passed

I have to extract values from one string of input, and using those values to calculates the days passed

Here's the main code

clear,clc
%1. Get Inputs
intDate = input('Enter Date in yyyy/mm/dd format: ','s');
intYear = intDate(1:4);
intDay = intDate(9:10);
intMonth = intDate(6:7);
if isLeapYear(intYear)
  intMonth = intDate(6:7);
if ~isValidMonth(intMonth)
  msgbox('Pleaes enter a valid Month');
  return
end
if ~isValidDate(intDay,intMonth,intYear)
  msgbox('Pleaes enter a valid Day');
  return
end
if intMonth==1||intMonth==3
  intDaysPassed = ((((intMonth-1)*30)+intDay)-1);
elseif intMonth==2||intMonth==4||inthMonth==5||intMonth==8
  intDaysPassed = (((intMonth-1)*30)+intDay);
elseif intMonth==6||intMonth==7||intMonth==9||intMonth==10
  intDaysPassed = (((intMonth-1)*30)+(intDay+1));
elseif intMonth==11||intMonth==12
  intDaysPassed = (((intMonth-1)*30)+(intDay+2));
end
else
  strMessage = 'Please enter a valid leap year';
  msgbox(strMessage)
  return
end

*

Here's the code for the month

function Month = isValidMonth(intMonth)
a = (intMonth <=12);
Month = (a~=0);
end
****

Here's the code for the day

function Day = isValidDate(intDay,intMonth,intYear)
DaysInMonth = [31 28 31 30 31 30 31 31 30 31 30 31]; % A 1x12 array
if isLeapYear(intYear)
  DaysInMonth(2) = 29;
end
Day = (intDay >= 1) && (intDay <= DaysInMonth(intMonth));
end

*

Here's the code for the Year

function LeapYear = isLeapYear(intYear)
a = mod(intYear,400);
b = mod(intYear,100);
c = mod(intYear,4);
LeapYear = ((a==0)||(b~=0 && c==0));
end

Everytime I try to run it, it keeps giving me these errors

Ex. I would enter 2012/03/15 as the input

Operands to the and && operators must be convertible to logical scalar values.

Error in isLeapYear (line 5) LeapYear = ((a==0)||(b~=0 && c==0));

Error in Homework6_Question2 (line 9) if isLeapYear(intYear)

How do I convert the matrix values to scalar values so I could apply the calculation for the days passed? Is there anything else wrong in my codes? Please help !

Thank you so much !

Answer 1

[Bjorn Gustavsson]

Look at matlab's datestr, datenum and datevec functions instead.

[Travis]

I have to use the matrix vector in Matlab to calculate, though. It's an assignment for school. And I can't seem to figure out how to convert the matrix values to the appropriate values to proceed with the calculations.

[Iain]

str2double is what I reckon you're missing.

 str = '1999';
 val = 1999;
 number = str2double(str);
 number == val %returns 1 if number equals val.

[Travis]

Thank you ! Thank you ! You're awesome ! It works perfectly !