Return X and Y from count value

[rogster001]

does anybody have a formula that will allow me to get the Y and X of a location in a 2d array based on its number counting along through the elements, so in a 5x5 array count at 3, 4 is 19, at 2, 2 count is 12 etc.

i made up the below one but i found it only works with square areas, rectangles give lots of - X coordinate numbers and incorrect Y coordinate ones, strangely the chart output still comes out ok..?

i am rubbish at maths as you can see

 Ycoord = element_number / Y_Range;
 Xcoord  = element_number - X_Range * Ycoord;

i have done a formula to give me the element number from the co-ordinates but i cant reverse it properly

[quzah]

All you need is the number of columns in the array.

int array[ ROWS ][ COLS ];
...

number = 23;
row = number / COLS;
col = number % COLS;

Say COLS is 4.
row = 23 / 4 = 5
col = 23 % 4 = 3



Quzah.

[rogster001]

superb, thanks for the help!