how to plot a method in matlab

I'm trying to plot a method i defined for calculating the probability of n people having different birthday which has the following code:

function y = d_birthday( n )

year = 365;
y=1;

for i=0:n-1
    y = y*((year-i)/year);
end
end

and in the command line I'm defining a vector variable x to hold values from 1:100

x=1:100;

but when I try to plot my method using x using this statement

plot(x,d_birthday(x))

all my values exhibit the same value, how do I fix it so that each value of x has it own value

Answer 1

[Roger Stafford]

   year = 365;
   y=ones(year,1);
   for i=2:year
     y(i) = y(i-1)*((year-i+1)/year);
   end

[raed khader]

doesn't this treat each input as a vector in itself? for example if x=1:10 then each x will have as many values as it's value so x=10 will have 10 values, which is causing me to have the following error

Vectors must be the same lengths.

can you show me how to plot your method?

[Roger Stafford]

   x = (1:year)';
   plot(x,y,'y-')

or

   x = 1:100
   plot(x,y(1:100),'y-')

The vectors you plot must be of the same size.

[Walter Roberson]

Or just plot(y, 'y-') . When the x are 1:length(y) then you can omit the x.