D3.js pie.startAngle()函数

D3.js中的pie.startAngle()函数用于设置饼图的起始角度。当指定一个角度时，它将起始角度设置为给定的角度或函数并返回一个饼图生成器。未指定角度时，返回当前起始角度访问器，默认为无起始角度。

句法：

pie.startAngle( angle )

参数：此函数接受如上所述和下文所述的单个参数。

• 角度：它是一个数字或函数，以弧度指定起始角度。它是一个可选参数。

返回值：此函数不返回任何内容。

下面给出了 D3.js 中pie.startAngle()函数的几个示例；

示例 1：

HTML

 

    
    

 

    
        
            
                GeeksforGeeks
            
            
                pie.startAngle()
            
        
        
        
    
     
    
 
        // Data to be added in the pie chart
        var data = [
            { "property": "p5", "value": 19 },
            { "property": "p5", "value": 12 },
            { "property": "p4", "value": 11 },
            { "property": "p3", "value": 10 },
            { "property": "p2", "value": 9 },
            { "property": "p1", "value": 5 },
            { "property": "p3", "value": 10 },
            { "property": "p2", "value": 9 },
            { "property": "p1", "value": 5 },
        ]
 
        // Selecting SVG using d3.select()
        var svg = d3.select("svg");
 
        // Creating Pie generator
        var pie = d3.pie()
            .value((d) => { return d.value })
            // Use of pie.startAngle() Function
            .startAngle(1)
            (data);
        // Creating arc
        var arc = d3.arc()
            .innerRadius(0)
            .outerRadius(80);
 
        let g = svg.append("g")
            .attr("transform", "translate(150,120)");
 
        // Grouping different arcs
        var arcs = g.selectAll("arc")
            .data(pie)
            .enter()
            .append("g");
 
        // Appending path
        arcs.append("path")
            .attr("fill", (data, i) => {
                return d3.schemeSet3[i];
            })
            .attr("d", arc);
    

 

输出：

示例 2：

HTML

 

    
    

 

    
        
            
                GeeksforGeeks
            
            
                pie.startAngle()
            
        
        
        
    
     
    
        // Data to be added in the pie chart
        var data = [
            { "property": "p5", "value": 19 },
            { "property": "p5", "value": 12 },
            { "property": "p4", "value": 11 },
            { "property": "p3", "value": 10 },
            { "property": "p2", "value": 9 },
            { "property": "p1", "value": 5 },
            { "property": "p3", "value": 10 },
            { "property": "p2", "value": 9 },
            { "property": "p1", "value": 5 },
        ]
 
        // Selecting SVG using d3.select()
        var svg = d3.select("svg");
 
        // Creating Pie generator
        var pie = d3.pie()
            .value((d) => { return d.value })
            // Use of pie.startAngle() Function
            .startAngle(5)
            (data);
        // Creating arc
        var arc = d3.arc()
            .innerRadius(40)
            .outerRadius(80);
 
        let g = svg.append("g")
            .attr("transform", "translate(150,120)");
 
        // Grouping different arcs
        var arcs = g.selectAll("arc")
            .data(pie)
            .enter()
            .append("g");
 
        // Appending path
        arcs.append("path")
            .attr("fill", (data, i) => {
                return d3.schemeSet3[i];
            })
            .attr("d", arc);
    

 

输出：