# Quantitative Scales

    var colorScale = d3.scale.quantile()

            .domain([d3.max(dataset) / 4, d3.max(dataset) / 2 , 3*d3.max(dataset) / 4, d3.max(dataset)])

            .range(["#9c9ede","#6b6ecf","#5254a3", "#393b79"]);
So the code divide the value into 4 range, if the value smaller than 1/4 max value, then it use #9c9ede color;
from 1/4 - 1/2: #6b6ecf
...
from 3/4 - 1: #393b79

 var q = d3.scale.quantize().domain([0, 1]).range(['a', 'b', 'c']);

 //q(0.3) === 'a', q(0.4) === 'b', q(0.6) === 'b', q(0.7) ==='c';

 //q.invertExtent('a') returns [0, 0.3333333333333333]





### use:





.attr('fill', colorScale);






<!DOCTYPE html>

<html>

<head lang="en">

    <meta charset="UTF-8">

    <title></title>

    <script src="../bower_components/underscore/underscore-min.js"></script>

    <script src="../ventor/d3.min.js"></script>

    <style type="text/css">

        body

        {

            padding-top: 50px;

            padding-left: 100px;

        }

        #chartArea {

            width: 400px;

            height: 300px;

            background-color: #CCC;

        }

        .bar

        {

            display: inline-block;

            width: 20px;

            height: 75px; /* Gets overriden by D3-assigned height below */

            margin-right: 2px;

           /* fill: teal; *//* SVG doesn't have background prop, use fill instead*/

            z-index:99;

        }

    </style>

</head>

<body>

<section id="chartArea"></section>

<script>

    var dataset = _.map(_.range(30), function(num) {

        return Math.random() * 50;

    }), //reandom generate 15 data from 1 to 50

            w = 400, h = 300;

    var svg = d3.select('#chartArea').append('svg')

            .attr('width', w)

            .attr('height', h); //svg deosn't need 'px'

    var yScale = d3.scale.linear()

            .domain([0, d3.max(dataset) * 1.1]) //d3.max(dataset), set the max val of database

            .range([0, h]);

    var xScale = d3.scale.ordinal()

            .domain(dataset)

            .rangeBands([0,w],0.3, 0.1);

//    var colorScale = d3.scale.category20c();

    var colorScale = d3.scale.quantile()

            .domain([d3.max(dataset) / 4, d3.max(dataset) / 2 , 3*d3.max(dataset) / 4, d3.max(dataset)])

            .range(["#9c9ede","#6b6ecf","#5254a3", "#393b79"]);

    svg.selectAll('div')

            .data(dataset)

            .enter()

            .append('rect')// svg doesn't have div, use rect instead

            .attr('class', "bar")

            .attr('width', xScale.rangeBand())

            .attr('x', function(each_data, index){

                return xScale(each_data);

            })

            .attr('y', function(each_data){

                return h-yScale(each_data);

            })

            .attr('height', function(each_data, i){

                return yScale(each_data);

            })

            .attr('fill', colorScale);

</script>

</body>

</html>


												


											
[D3] 7. Quantitative Scales的更多相关文章
	

    
								
  1. 【D3.V3.js系列教程】--（十二）坐标尺度
		
    [D3.V3.js系列教程]--(十二)坐标尺度 1.多种类型的缩放尺度 Quantitative Scales Linear Scales Identity Scales Power Scales  ...
    
		
    2. 
						
  2. D3 JS study notes
		
    如何使用d3来解析自定义格式的数据源? var psv = d3.dsvFormat("|"); // This parser can parse pipe-delimited t ...
    
		
    3. 
						
  3. 【D3 API 中文手冊】
		
    [D3 API 中文手冊] 声明:本文仅供学习所用,未经作者同意严禁转载和演绎 <D3 API 中文手冊>是D3官方API文档的中文翻译. 始于2014-3-23日,基于VisualCre ...
    
		
    4. 
						
  4. D3——scale
		
    d3.scale 比例尺 “Scales are functions that map from an input domain to an output range” Domains 定义域 和 R ...
    
		
    5. 
						
  5. [D3] Build a Column Chart with D3 v4
		
    Column and bar charts are staples of every visualization library. They also make a great project for ...
    
		
    6. 
						
  6. [D3] Convert Dates to Numeric Values with Time Scales in D3 v4
		
    Mapping abstract values to visual representations is what data visualization is all about, and that’ ...
    
		
    7. 
						
  7. [D3] Convert Input Data to Output Values with Linear Scales in D3
		
    Mapping abstract values to visual representations is what data visualization is all about, and that’ ...
    
		
    8. 
						
  8. [D3] Create Labels from Non-numeric Data with Ordinal Scales in D3 v4
		
    When your data contains discrete, non-numeric property values that you need to format or convert bef ...
    
		
    9. 
						
  9. [D3] Create Labels from Numeric Data with Quantize Scales in D3 v4
		
    Sometimes data needs to be converted from a continuous range, like test scores, to a discrete set of ...
    
		
    10. 
		

	


随机推荐
	

    
									
  1. 【技术帖】解决 Hudson jenkins 连接等待中 - Waiting for next av
			
    今天构建项目发现如下问题: jenkins 连接等待中 - Waiting for next available executor 左下角那块一直不运行构建,一直在连接等待. 于是,进入一级页面, 右 ...
    
			
    2. 
						
  2. 一篇文章让你读懂 OpenStack 的起源、架构和应用
			
    OpenStack 是一个面向 IaaS 层的开源项目,用于实现公有云和私有云的部署及管理.拥有众多大公司的行业背书和数以千计的社区成员, OpenStack 被看作是云计算的未来.目前 OS 基金会 ...
    
			
    3. 
						
  3. java api如何获取kafka所有Topic列表,并放置为一个list
			
    kafka内部所有的实现都是通过TopicCommand的main方法,通过java代码调用API,TopicCommand.main(options)的方式只能打印到控制台,不能转换到一个list. ...
    
			
    4. 
						
  4. 【POJ 3167】Cow Patterns （KMP+树状数组）
			
    Cow Patterns Description A particular subgroup of K (1 <= K <= 25,000) of Farmer John's cows l ...
    
			
    5. 
						
  5. 创建支持CRUD(增删改查)操作的Web API(二)
			
    一:准备工作 你可以直接下载源码查看 Download the completed project.     下载完整的项目 CRUD是指“创建(C).读取(R).更新(U)和删除(D)”,它们是四个 ...
    
			
    6. 
						
  6. Android 使用WakeLock
			
           为了延长电池的使用寿命,Android设备会在一段时间后使屏幕变暗,然后关闭屏幕显示,最后停止CPU.WakeLock是一个电源管理系统服务功能,应用程序可以使用它来控制设备的电源状态. ...
    
			
    7. 
						
  7. Linux查看硬件信息，主板型号及内存硬件，驱动设备，查看设备，查看CPU。
			
    用硬件检测程序kuduz探测新硬件:service kudzu start ( or restart) 查看CPU信息:cat /proc/cpuinfo 查看板卡信息:cat /proc/pci 查 ...
    
			
    8. 
						
  8. 【转】Android中intent传递对象和Bundle的用法
			
    原文网址:http://blog.csdn.net/lixiang0522/article/details/8642202 android中的组件间传递的对象一般实现Parcelable接口,当然也可 ...
    
			
    9. 
						
  9. java获取天气预报的信息
			
    运行效果: 主要功能: 1,jsp页面输入省份和城市 根据条件获取当地的天气信息 2,java代码 利用第三方的省份和城市的路径地址 本工程主要实现java获取天气预报的信息步骤1,创建工程weath ...
    
			
    10. 
						
  10. HDOJ/HDU 1075 What Are You Talking About(字符串查找翻译~Map)
			
    Problem Description Ignatius is so lucky that he met a Martian yesterday. But he didn't know the lan ...
    
			
    11.