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Non è possibile visualizzare l'immagine. Consiglio Nazionale delle Ricerche Istituto di Calcolo e Reti ad Alte Prestazioni Overview of Standard Graph File Formats A. Messina Rapporto Tecnico N.: RT-ICAR-PA-2018-06 Dicembre 2018 Consiglio Nazionale delle Ricerche, Istituto di Calcolo e Reti ad Alte Prestazioni (ICAR) – Sede di Cosenza, Via P. Bucci 41C, 87036 Rende, Italy, URL: www.icar.cnr.it – Sede di Napoli, Via P. Castellino 111, 80131 Napoli, URL: www.na.icar.cnr.it – Sede di Palermo, Viale delle Scienze, 90128 Palermo, URL: www.pa.icar.cnr.it Non è possibile visualizzare l'immagine. Consiglio Nazionale delle Ricerche Istituto di Calcolo e Reti ad Alte Prestazioni Overview of Standard Graph File Formats A. Messina1 Rapporto Tecnico N.: RT-ICAR-PA-2018-06 Dicembre 2018 1 Istituto di Calcolo e Reti ad Alte Prestazioni, ICAR-CNR, Sede di Palermo, Via Ugo La Malfa n. 153, 90146 Palermo. I rapporti tecnici dell’ICAR-CNR sono pubblicati dall’Istituto di Calcolo e Reti ad Alte Prestazioni del Consiglio Nazionale delle Ricerche. Tali rapporti, approntati sotto l’esclusiva responsabilità scientifica degli autori, descrivono attività di ricerca del personale e dei collaboratori dell’ICAR, in alcuni casi in un formato preliminare prima della pubblicazione definitiva in altra sede. Index 1 INTRODUCTION...................................................................................................... 6 2 CSV FORMAT ........................................................................................................... 7 2.1 Introduction ......................................................................................................................... 7 2.2 CSV Graphs .......................................................................................................................... 7 2.2.1 Edge list ........................................................................................................................... 7 2.2.2 Adjacency list ................................................................................................................... 7 2.2.3 Mixed .............................................................................................................................. 8 2.2.4 Matrix .............................................................................................................................. 8 3 GRAPHVIZ DOT FORMAT ..................................................................................... 9 3.1 Introduction ......................................................................................................................... 9 3.2 The DOT Language ............................................................................................................... 9 3.2.1 Subgraphs and Clusters .................................................................................................. 10 3.2.2 Lexical and Semantic Notes ............................................................................................ 11 3.3 Examples ........................................................................................................................... 13 3.3.1 Basic example ................................................................................................................ 13 3.3.2 Labels ............................................................................................................................ 13 3.3.3 Adjacency lists ............................................................................................................... 13 4 GDF FORMAT ........................................................................................................ 14 4.1 Introduction ....................................................................................................................... 14 4.2 The GUESS .gdf format ....................................................................................................... 14 4.3 Examples ........................................................................................................................... 16 4.3.1 Basic example ................................................................................................................ 16 4.3.2 Example with edge weight ............................................................................................. 16 4.3.3 Various attributes .......................................................................................................... 17 4.3.4 Working with texts ......................................................................................................... 17 5 GML FORMAT ........................................................................................................ 18 5.1 Introduction ....................................................................................................................... 18 5.2 Key issues of GML .............................................................................................................. 18 5.3 GML Syntax ........................................................................................................................ 19 5.3.1 How Graphs and Other Data Structures are Represented ............................................... 20 5.3.2 Restrictions .................................................................................................................... 21 5.3.3 How to Represent Common Data Structures .................................................................. 22 5.3.4 Order of Attributes ........................................................................................................ 23 5.3.5 Unknown Attributes ....................................................................................................... 23 5.3.6 Consistency.................................................................................................................... 23 5.4 Examples ........................................................................................................................... 24 5.4.1 Basic example ................................................................................................................ 24 5.4.2 Labels ............................................................................................................................ 24 6 GRAPHML FORMAT ............................................................................................. 26 6.1 Introduction ....................................................................................................................... 26 6.2 Basic Concepts ................................................................................................................... 26 6.2.1 The Header .................................................................................................................... 27 6.2.2 The Graph ...................................................................................................................... 28 6.2.3 Declaring a Graph .......................................................................................................... 28 6.2.4 Declaring a Node............................................................................................................ 29 6.2.5 Declaring an Edge .......................................................................................................... 29 6.3 GraphML-Attributes ........................................................................................................... 29 6.3.1 GraphML-Attributes Example ......................................................................................... 30 6.3.2 Declaring GraphML-Attributes ....................................................................................... 31 6.3.3 Defining GraphML-Attribute Values................................................................................ 32 7 GEXF ........................................................................................................................ 33 7.1 Introduction ....................................................................................................................... 33 7.2 Basic Concepts ................................................................................................................... 33 7.2.1 Header........................................................................................................................... 34 7.2.2 Network Topology ......................................................................................................... 34 7.2.3 Declaring a Graph .......................................................................................................... 35 7.2.4 Declaring a Node............................................................................................................ 35 7.2.5 Declaring an Edge .......................................................................................................... 36 7.3 Network Data .................................................................................................................... 36 7.3.1 Data types ..................................................................................................................... 37 7.3.2 Attributes Example ........................................................................................................ 37 7.3.3 Declaring Attributes ....................................................................................................... 38 7.3.4 Defining Attribute
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