DPM_flowcharts.doc Page F-1 of 9 Rüdiger Siol :28

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1 Contents F TOOLS TO SUPPORT THE DOCUMENTATION... F-2 F.1 GRAPHIC SYMBOLS AND THEIR APPLICATION (DIN )... F-2 F.1.1 Flow of control... F-3 F.1.2 Terminators and connectors... F-4 F.1.3 Lines, arrows and communication links... F-5 F.1.4 Annotations... F-5 F.1.5 Data... F-6 F.2 NASSI-SHNEIDERMAN FLOWCHART SYMBOLS (DIN )... F-7 F.2.1 Process... F-7 F.2.2 Serial... F-7 F.2.3 Iterative... F-8 F.2.4 Selective choice... F-9 DPM_flowcharts.doc Page F-1 of 9 Rüdiger Siol

2 F Tools to support the documentation F.1 Graphic symbols and their application (DIN ) Flowcharts Darstellungsarten (type of representation) (DF) Datenflußplan (data flowchart) (PA) Programmablaufplan (programming flowchart) (PN) Programmnetz (program network) (DN) Datennetz (data network) (PH) Programmhierarchie (program hierarchy) (DH) Datenhierarchie (data hierarchy) (KP) Konfigurationsplan (configuration plan) (r.siol) An important tool of programming is the flowchart, or block diagram, which allows the programmer to plan the sequence of operations in a program before writing it. In any problem that is even moderately complex the interrelationships within it are difficult to keep clearly in mind without some visual representation. A flowchart provides this visual assistance. It also greatly facilitates communication between programmers and is a valuable part of the documentation of a program. A flowchart is made up of a set of boxes, the shapes of which indicate the nature of the operations described in the boxes, along with connecting lines and arrows that show the "flow of control" between the various operations. DPM_flowcharts.doc Page F-2 of 9 Rüdiger Siol

3 F.1.1 symbols: Flow of control For our purposes here the notation, which is quite simple, contains the following o A rectangle indicates any processing operation except a decision. o A diamond indicates a decision. The lines leaving the box are labeled with the decision results that cause each path to be followed. o A trapezoid indicates an input or output operation. Sinnbilder (symbols) Verarbeitung / Verarbeitungseinheiten Verarbeitungseinheit, allgemein (processing unit) Manuelle Verarbeitung (manual operation) Verzweigung (decision) (r.siol) DPM_flowcharts.doc Page F-3 of 9 Rüdiger Siol

4 F.1.2 Terminators and connectors o An oval indicates the beginning or ending point of the program. o A small circle indicates a connection between two points in a flowchart, where a connecting line would be too clumsy. Sinnbilder (Symbols) their representation Grenzstelle - zur Umwelt (terminator) (Start and End of a Sequence, Source and Destination of Data) Verbindungsstelle (connector) A connector is a point for a preliminary stop of the program flow, the connector with the same name shall be used to continue; i.e. on another sheet. (r.siol) DPM_flowcharts.doc Page F-4 of 9 Rüdiger Siol

5 F.1.3 Lines, arrows and communication links o Arrows indicate the direction of flow through the flowchart; every line should have an arrow on it. Sinnbilder Verbindungen Verbindung (line) Verarbeitungsfolge Zugriffsmöglichkeit Zugriffsweg Über-/Unterordnung Zusammenfassung / Unterteilung Datenübertragungsweg (communication link) (r.siol) F.1.4 Annotations o Comments or annotations allow an additional description inside the flowcharts. Sinnbilder (Symbols) Comments Bemerkung (annotation) A comment may be inserted annywhere in the flowchart. It should contain short but usefull information. (r.siol) DPM_flowcharts.doc Page F-5 of 9 Rüdiger Siol

6 F.1.5 Data Symbols about the data Sinnbilder (Symbols) Data Daten, allgemein (general data representation) Maschinell zu verarbeitende Daten (data to be processed by machine) Manuell zu verarbeitende Daten (data to be processed by manual operation) (r.siol) DPM_flowcharts.doc Page F-6 of 9 Rüdiger Siol

7 F.2 Nassi-Shneiderman flowchart symbols (DIN ) F.2.1 Process P Imperative Block P F.2.2 Serial P1 Serial P2 DPM_flowcharts.doc Page F-7 of 9 Rüdiger Siol

8 F.2.3 Iterative Condition Pre-tested iteration Process Process Post-tested iteration Condition Continuous iteration Process DPM_flowcharts.doc Page F-8 of 9 Rüdiger Siol

9 F.2.4 Selective choice C S P Condition (Conditional expression) Specific Selection Process (Block) S C Monadic Selective P C Dyadic Selective S1 S2 P1 P2 C Multiple exclusive Selective S 1 S n Sn P 1 P n-1 P n DPM_flowcharts.doc Page F-9 of 9 Rüdiger Siol