trouble with introduction to d3.js

d3.js, html, javascript, svg

Solution

You need to actually select the svg element first before using `svg.selectAll`.

var svg = d3.select(document.getElementById('sampleSVGId')),
    circle = svg.selectAll('circle');

Problem

So I'm just starting d3.js and I keep getting a JavaScript error and I've no idea why. I've just created three circles with svg and want to select them with d3. Here's my code: ``` <!DOCTYPE HTML> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> <script src="http://d3js.org/d3.v3.min.js"></script> <script type="text/javascript"></script> </head> <body> <svg width="360" height="180"> <circle class="little" cx="180" cy="45" r="12"></circle> <circle class="little" cx="60" cy="90" r="12"></circle> <circle class="little" cx="300" cy="135" r="12"></circle> </svg> <script type="text/javascript"> var circle = svg.selectAll("circle"); </script> </body> </html> ``` This is supposed to select the circles on the page so I can manipulate them but I keep getting a reference error in my Web Console that says svg is not defined? But the introductory tutorial doesn't say anything about defining svg?

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