how to sort list eg: I have point data {x1=153.25,y1=200}{x2=152.35,y2=200}{x3=151.75,y3=200}{x4=151.95,y4=200.5}{x5=151.75,y5=199.5}. For same value of y, x should be sorted in ascending order. for these list will be like {x5,y5; x3,y3; x4,y4; x1,y1; x2,y2}. I am new to c# thanks