How do you calculate the area in square meter with irrigular shape?

Answer 1

Here are three possible methods. You may have to use a scaled version of the original shape if it is too big: Method A (exact): This is only possible if the shape can be partitioned into a manageable number of smaller shapes such that the areas of these smaller shapes can be measured. Add up the areas of all the constituent shapes. Method B (statistical): Trace the shape onto a sheet of paper with a square grid marked on it. Count all the squares where half or more of the square lie inside the shape. Do not count any square if less than half of it is inside the shape. Let us call this number S. If you have scaled down the original shape, then multiply S by the square of your scaling factor. For example if your tracing is a tenth as long and a tenth as wide, the area will be S*10*10. Method C (physical): Trace the shape onto something of uniform thickness - paper or card or board. Cut this shape out and weight it. Lets call this weight W. Also cut out a shape of known area. This could be 1 sq cm or 5 sq cm or whatever, say U. Weigh this shape, say X. Then the area of the original shape is W/X times as big as your "standard". That is, its area is U*W / X sq units. Remember to scale up from the size of the unit to 1 sq metre). The accuracy of this method depends on the uniformity of the sheet material used and the precision of the weighing apparatus. Statistically, this should approximate to