scaling geo coordinates in D3.js -


i draw circle in each coordinate. using width, height, , coordinates, how scale coordinates? i'm new d3.js , guess i'm doing wrong projection part. 

var width = 200,     height = 200; var svg = d3.select("body")             .append("svg")             .attr("width", width)             .attr("height", height);  var coordinates = [ [43.08803611,-79.06312222],                      [43.09453889,-79.05636667] ];  var group = svg.append('g');  var projection = d3.geo.mercator()                         .translate([width,height]);  var projectedcoordinates = []; (var i=0; i<coordinates.length; i++) {     projectedcoordinates[i] = projection(coordinates[i]); }  group.selectall("circle")     .data(projectedcoordinates)     .enter()     .append("circle")     .attr("r",4)     .attr("cx", function(d){ return d[0]; })     .attr("cy", function(d){ return d[1]; });

you there, problem projection projecting coordinates outside drawing area. can use .center() function tell projection center , .scale() "zoom in". should translate projection half width , height of container, otherwise center in bottom right corner.

the following example values should enable see points:

var projection = d3.geo.mercator()                     .center([43.09, -79.06])                     .scale(50000)                     .translate([width/2,height/2]);

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