xj integer (for some or all j = 1,2,...,n). This problem is called the (linear) integer-programming problem. It is said to be a mixed integer program. when some, but not all, variables are restricted to be integer, and is called a pure integer program when all. decision variables must be integers. As we saw in the preceding chapter, if the constraints are of a network.
Anion gap: A measurement of the interval between the sum of routinely measured cations minus the sum of the routinely measured anions in the blood. The anion gap = (Na+ + K+) - (Cl- + HCO3-) where Na-is sodium, K+ is potassium, Cl-is chloride, and HCO3- is bicarbonate. The anion gap can be normal, high, or low.
However, routine test do not measure all types of ions. The anion gap is representative of how many ions are not accounted for by the lab measurements used in the calculation. These unmeasured ions are mostly anions, which is why the value is called the anion gap..