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A decision-to-decision path, or DD-path, is a path of execution (usually through a flow graph representing a program, such as a flow chart) between two decisions. More recent versions of the concept also include the decisions themselves in their own DD-paths. ==Definition== In Huang's 1975 paper,〔 The definition given there is citing: "Fortran automated verification system Level 1 — user's guide, Program Validation Project, General Research Corp., October 1974."〕 a decision-to-decision path is defined as path in a program's flowchart such that all the following hold (quoting from the paper): * its first constituent edge emanates either from an entry node or a decision box; * its last constituent edge terminates either at a decision box or at an exit node; and * there are no decision boxes on the path except those at both ends Jorgensen's more recent textbooks restate it in terms of a program's flow graph (called a "program graph" in that textbook).〔 First define some preliminary notions: chain and a maximal chain. A chain is defined as a path in which: * initial and terminal nodes are distinct, and * all interior nodes have in-degree = 1 and out-degree = 1. A maximal chain is a chain that is not part of a bigger chain. A DD-path is a set of nodes in a program graph such that one of the following holds (quoting and keeping Jorgensen's numbering, with comments added in parenthesis):〔 # It consists of a single node with in-degree = 0 (initial node) # It consists of a single node with out-degree = 0 (terminal node) # It consists of a single node with in-degree ≥ 2 or out-degree ≥ 2 (decision/merge points) # It consists of a single node with in-degree = 1 and out-degree = 1 # It is a maximal chain of length ≥ 1. According to Jorgensen (2013), in Great Britain and ISTQB literature, the same notion is called linear code sequence and jump (LCSAJ).〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Decision-to-decision path」の詳細全文を読む スポンサード リンク
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