Software Engineering Tutorials

Home| Forums | Join Google Group | Join Yahoo Group | Jobs

Earn Money
Trading Forex Online
  Paramount Airways
  Free Data Recovery
Cargo
Job Portal
  HSBC Investment
Management
Cheap Web Hosting
  Make Trip
  Cheap Air Travel
Leisure Hotel
  Free Air Travel
  Mutual Fund Informations
Cheapest Cellular Plan
Free Sexy Indians
  Call Center Software
  Hot Indian

Software Engineering Tutorials

program. It defines the number of independent paths in the basis set and thus provides an upper
bound for the number of tests that must be performed. The Basis Set An independent path is any path through a program that introduces at least one new set of
processing statements (must move along at least one new edge in the path). The basis set is not
unique . Any number of different basis sets can be derived for a given procedural design. Cyclomatic complexity, V(G), for a flow graph G is equal to 1. The number of regions in the flow graph. 2. V(G) = E - N + 2 where E is the number of edges and N is the number of nodes. 3. V(G) = P + 1 where P is the number of predicate nodes. Deriving Test Cases 1. From the design or source code, derive a flow graph. 2. Determine the cyclomatic complexity of this flow graph. o Even without a flow graph, V(G) can be determined by counting the number of
conditional statements in the code. 3. Determine a basis set of linearly independent paths. o Predicate nodes are useful for determining the necessary paths. 4. Prepare test cases that will force execution of each path in the basis set. o Each test case is executed and compared to the expected results. Automating Basis Set Derivation The derivation of the flow graph and the set of basis paths is amenable to automation. A software
tool to do this can be developed using a data structure called a graph matrix. A graph matrix is a
square matrix whose size is equivalent to the number of nodes in the flow graph. Each row and
column correspond to a particular node and the matrix corresponds to the connections (edges)
between nodes. By adding a link weight to each matrix entry, more information about the control
flow can be captured. In its simplest form, the link weight is 1 if an edge exists and 0 if it does
not. But other types of link weights can be represented: · the probability that an edge will be executed, · the processing time expended during link traversal, · the memory required during link traversal, or · the resources required during link traversal. Graph theory algorithms can be applied to these graph matrices to help in the analysis necessary
to produce the basis set.