Halstead's Software Science

Answer 1

Halstead proposed the first analytic laws for computer science by using a set of primitive measures. these can be derived once the design phase is complected and the code is generated. these measures are listed below * n1= number of distinct operators in a program * n2= number of distinct operands in a program * N1= total numbers of operators * N2= total number of operands

By using these measures,Halstead developed an expression for overall program length,program volume,program difficulty,development effort and so on.

Program length (N) can be calculated by using equation:

N = n1log2 n1 + n2log2 n2

Program volume (V) can be calculated by using equation:

V = N log2(n1+n2)

Note that the program volume depends on the programming language used and respesents the volume of information (in bits) required to specify a program.

Volume ratio (L) can be calculated by using the following equation:

---- volume of the actual program

Where value of L must be less than 1. Volume ratio can be also calculated by

Program difficulty level (D) and effort(E) can be calculated by equations: D = (n1/2)*(N2/n2) E = D * V