PCO stands for Potential Change Order (construction management). Suggest new definition. This definition appears somewhat frequently and is found in the following Acronym Finder categories: 1  Business, finance, etc.
Quick Answer. The Roman numeral XIX is the number 19. X is the number 10, and I is the number one. When a lower number is placed in front of a larger number, it indicates subtraction; IX is the same as 10 minus one, which equals nine. The Ancient Romans used different letters to represent numbers.
Ï Xic is the sum of elements from row i of matrix X. S is a r x 1 column matrix whose elements are row sums from matrix X. Matrix-wide. And finally, it is possible to compute a grand sum of all the elements in matrix X, as shown below. 1r' X1c = Ï Xrc = S. where. 1r is an r x 1 sum vector, and 1r' is its transpose.