DAG圖是有向無(wú)環(huán)圖(Directed Acyclic Graph)的縮寫(xiě),通常用于描述一些計(jì)算過(guò)程中的依賴(lài)關(guān)系。在實(shí)際的應(yīng)用場(chǎng)景中,DAG圖通過(guò)JSON格式進(jìn)行數(shù)據(jù)的存儲(chǔ)和傳輸。
{ "nodes": [ {"id": "A", "type": "start"}, {"id": "B", "type": "data"}, {"id": "C", "type": "data"}, {"id": "D", "type": "compute"}, {"id": "E", "type": "end"} ], "edges": [ {"source": "A", "target": "B"}, {"source": "A", "target": "C"}, {"source": "B", "target": "D"}, {"source": "C", "target": "D"}, {"source": "D", "target": "E"} ] }
該JSON示例展示了一個(gè)簡(jiǎn)單的計(jì)算過(guò)程,其中"A"節(jié)點(diǎn)為起點(diǎn),"B"和"C"節(jié)點(diǎn)為數(shù)據(jù)節(jié)點(diǎn),"D"節(jié)點(diǎn)為計(jì)算節(jié)點(diǎn),"E"節(jié)點(diǎn)為終點(diǎn)。其中,"B"和"C"節(jié)點(diǎn)的數(shù)據(jù)作為輸入,經(jīng)過(guò)計(jì)算后輸出至"E"節(jié)點(diǎn)。
在DAG圖的節(jié)點(diǎn)中,除了起點(diǎn)和終點(diǎn)節(jié)點(diǎn)外,還有數(shù)據(jù)節(jié)點(diǎn)和計(jì)算節(jié)點(diǎn)。其中,數(shù)據(jù)節(jié)點(diǎn)用于表示輸入和輸出的數(shù)據(jù)。計(jì)算節(jié)點(diǎn)用于表示計(jì)算的過(guò)程。節(jié)點(diǎn)的類(lèi)型在示例JSON中通過(guò)"type"字段進(jìn)行描述。
而在DAG圖的連邊中,"source"字段表示邊的起點(diǎn),"target"字段表示邊的終點(diǎn)。多條連邊表示節(jié)點(diǎn)之間存在多對(duì)依賴(lài)關(guān)系。