How to get area of a polygon in matlab

I have coordinates of a polygon saved in excel sheet, now i want to get the area of the polygon in matlab. First i will make the excel sheet read in matlab, then after that how to get the area?

Answer 1

[Stalin Samuel]

for example

data =[4,10;9,7;11,2;2,2;4,10]%from excel file
data(5,:) =data(1,:)
for i=1:max(size(data))-1
s(i)=data(i,1) *data(i+1,2)-data(i,2)*data(i+1,1)
end

area = abs(sum(s)/2)

Answer 2

[Thomas Koelen]

http://nl.mathworks.com/help/matlab/ref/polyarea.html