of saw kerf which may be made a selectable input to the computer to provide for use of different saws etc with the facts of the foregoing example if it be assumed that the saw kerf is 1 8 inch the optimum yield would no longer be one piece 30 inches long and another piece 24 inches long since this combination exceeds the available length when the kerf loss is considered instead the optimum yield becomes one 24 inch piece and two 14 inch pieces since this wastes only 15 8 inches of stock if however the bias for the computer had been set at four inches of allowable waste the optimum yield would no longer be that just stated but would instead be one 30 inch piece and one 20 inch piece with a waste of 33 4 inches of stock inasmuch as this combination produces longer pieces as stated above priority can be given to factors other than length in programming the computation of optimum yield as for example quantity of pieces that is if the manifest comprises a great number of pieces of the same dimension together with far fewer pieces of different dimensions the predominating length or lengths can be given priority so that the computer will choose that length or lengths in dis regard of other factors such as longest length when the occasion arises as when the other considerations are equal also such priorities can be weighted so as to take precedence in a given order or in a given.