Javascript D3对数标度

我正在研究这个可视化：

http://tinyurl.com/cul7oyg

在#scatterplot div上（在圆圈下方向下滚动）。我将Y比例设置为对数，并将第二个数字更改为1：

y=d3.scale.log（）.range（[h-60，1]）

域：

y.domain(d3.extent(data, function(d) {
    console.log(+d.netdonations/+d.population)
    console.log(y(+d.netdonations/+d.population))
    return +d.netdonations/+d.population;
}));

每当数据为0时，我会在日志中看到一堆“无穷大”值。负无穷渐近线应该很好地位于x-0y轴的左侧

    // set the stage
    var margin = {
        t : 30,
        r : 20,
        b : 20,
        l : 40
    }, w = 600 - margin.l - margin.r, h = 500 - margin.t - margin.b, x = d3.scale.linear().range([0, w]), y = d3.scale.log().range([h - 60, 1]),
    //colors that will reflect geographical regions
    color = d3.scale.category10();

    var svg = d3.select("#scatterplot").append("svg").attr("width", w + margin.l + margin.r).attr("height", h + margin.t + margin.b);

scatterplot.svg = svg

    // set axes, as well as details on their ticks
    var xAxis = d3.svg.axis().scale(x).ticks(20).tickSubdivide(true).tickSize(6, 3, 0).orient("bottom");

    var yAxis = d3.svg.axis().scale(y).ticks(20).tickSubdivide(true).tickSize(6, 3, 0).orient("left");

    // group that will contain all of the plots
    var groups = svg.append("g").attr("transform", "translate(" + margin.l + "," + margin.t + ")");

    // array of the regions, used for the legend
    var regions = getContinents;
    //["Asia", "Europe", "Middle East", "N. America", "S. America", "Sub-Saharan Africa"]

    // bring in the data, and do everything that is data-driven
    //d3.csv("./data/trust-business.csv", function(data) {

    // sort data alphabetically by region, so that the colors match with legend
    /*data.sort(function(a, b) {
     return d3.ascending(a.region, b.region);
     })
     console.log(data)*/

    var x0 = Math.max(-d3.min(data, function(d) {
        return d.gdppercap;
    }), d3.max(data, function(d) {
        return d.gdppercap;
    }));
    //x.domain([-100, 100]);
    //y.domain([180, 0])
    x.domain(d3.extent(data, function(d) {
        return +d.gdppercap;
    }));
    y.domain(d3.extent(data, function(d) {
        console.log(+d.netdonations/+d.population)
        console.log(y(+d.netdonations/+d.population))
        return +d.netdonations/+d.population;
    }));

scatterplot.x = x
scatterplot.y = y

    //console.log(d3.extent(data, function(d) {return +d.gdppercap;})); 
    //console.log(d3.extent(data, function(d) {return +d.netdonations/+d.population;}));

    // style the circles, set their locations based on data
    var circles = groups.selectAll("circle").data(data).enter().append("circle").attr("class", "circles").attr({
        cx : function(d) {
            return x(+d.gdppercap);
        },
        cy : function(d) {
            console.log(+d.netdonations/+d.population)
            console.log(y(+d.netdonations/+d.population))
            return y(+d.netdonations/+d.population);
        },
        r : 8,
        id : function(d) {
            return d.name;
        }
    }).style("fill", function(d) {
        return color(d.continent);
    });

    // what to do when we mouse over a bubble
    var mouseOn = function() {
        var circle = d3.select(this);

        // transition to increase size/opacity of bubble
        circle.transition().duration(800).style("opacity", 1).attr("r", 16).ease("elastic");

        // append lines to bubbles that will be used to show the precise data points.
        // translate their location based on margins
        svg.append("g").attr("class", "guide").append("line").attr("x1", circle.attr("cx")).attr("x2", circle.attr("cx")).attr("y1", +circle.attr("cy") + 26).attr("y2", h - margin.t - margin.b).attr("transform", "translate(40,20)").style("stroke", circle.style("fill")).transition().delay(200).duration(400).styleTween("opacity", function() {
            return d3.interpolate(0, 0.5);
        });

        svg.append("g").attr("class", "guide").append("line").attr("x1", +circle.attr("cx") - 16).attr("x2", 0).attr("y1", circle.attr("cy")).attr("y2", circle.attr("cy")).attr("transform", "translate(40,30)").style("stroke", circle.style("fill")).transition().delay(200).duration(400).styleTween("opacity", function() {
            return d3.interpolate(0, 0.5);
        });

        // function to move mouseover item to front of SVG stage, in case
        // another bubble overlaps it
        d3.selection.prototype.moveToFront = function() {
            return this.each(function() {
                this.parentNode.appendChild(this);
            });
        };

        // skip this functionality for IE9, which doesn't like it
        //if (!$.browser.msie) {
        if (navigator.appName !== 'ie') {
            circle.moveToFront();
        }
        //select()
    };
    // what happens when we leave a bubble?
    var mouseOff = function() {
        var circle = d3.select(this);

        // go back to original size and opacity
        circle.transition().duration(800).style("opacity", 0.5).attr("r", 8).ease("elastic");

        // fade out guide lines, then remove them
        d3.selectAll(".guide").transition().duration(100).styleTween("opacity", function() {
            return d3.interpolate(0.5, 0);
        }).remove();

        //mouseout
    };

    // run the mouseon/out functions
    circles.on("mouseover", mouseOn);
    circles.on("mouseout", mouseOff);

    // tooltips (using jQuery plugin tipsy)
    circles.append("title").text(function(d) {
        return d.name;
    });

    $(".circles").tipsy({
        gravity : 's'
    });

    // the legend color guide
    var legend = svg.selectAll("rect").data(regions).enter().append("rect").attr({
        x : function(d, i) {
            return (40 + i * 80);
        },
        y : h,
        width : 25,
        height : 12
    }).style("fill", function(d) {
        return color(d);
    });

    // legend labels
    svg.selectAll("text").data(regions).enter().append("text").attr({
        x : function(d, i) {
            return (40 + i * 80);
        },
        y : h + 24
    }).text(function(d) {
        return d;
    });

    // draw axes and axis labels
    svg.append("g").attr("class", "x axis").attr("transform", "translate(" + margin.l + "," + (h - 60 + margin.t) + ")").call(xAxis);

    svg.append("g").attr("class", "y axis").attr("transform", "translate(" + margin.l + "," + margin.t + ")").call(yAxis);

    svg.append("text").attr("class", "x label").attr("text-anchor", "end").attr("x", w + 50).attr("y", h - margin.t - 5).text("Per Capita GDP");

    svg.append("text").attr("class", "y label").attr("text-anchor", "end").attr("x", -20).attr("y", 45).attr("dy", ".75em").attr("transform", "rotate(-90)").text("Per Capita Net Donations");
    //});

---

Infinity

是JavaScript告诉您试图除以0的方式。在尝试执行除法之前，请始终检查分母是否不是0

Math.log(0)
=> -Infinity

是这样吗

y=d3.scale.log（）.clamp（true）.domain（[min，max]）.range（[min，max]）.nice（）

为你工作

编辑：它应该做：

d3.scale.log().clamp(true).domain([1,10]).range([0,100]).nice()(0)
0
d3.scale.log().domain([1,10]).range([0,100]).nice()(0)
NaN

谢谢，但我正在寻找如何避免D3中的除法为零。我的设置一定有问题。