tomgp/index.html

## readme.md

      
    Raw
  

              readme.md
            
          
    A little function that makes a sine wave generator with some simple properties:
the range over which it varies and the wavelength

  
## index.html
<!DOCTYPE html>
<html lang="en">
    <head>
        <meta charset="UTF-8">
        <meta name="viewport" content="width=device-width, initial-scale=1.0">
        <meta http-equiv="X-UA-Compatible" content="ie=edge">
        <title>Test</title>
        <script src="https://d3js.org/d3.v5.min.js"></script>
        <script src="index.js"></script>
    </head>
    <body>
        <svg width="500" height="500"></svg>
    </body>
    <script>
    //default is that it oscilates between -1 and 1
    //with one complete oscilation hapening every 1 unit of time

        function makeSinOscilator(range=[-1,1], waveLength = 1){
            waveLength = waveLength/(2*Math.PI);
            const scaleX = d3.scaleLinear()
                .domain([-1,1])
                .range(range)

            return (time) => scaleX( Math.sin(time/waveLength) );
        }

        const myOsc = makeSinOscilator([-2,2],0.5);
        const values = [];

        for(let t = 0; t<1; t += 0.01){
            values.push({x:t, y:myOsc(t)});
        }

        const scaleX =  d3.scaleLinear()
            .range([0,500])
            .domain(d3.extent(values, (d)=>d.x));

        const scaleY =  d3.scaleLinear()
            .range([480,20])
            .domain([-5, 5]);

        const line = d3.line()
            .x(d => scaleX(d.x))
            .y(d => scaleY(d.y));

        d3.select('svg')
            .selectAll('path')
                .data([values])
            .enter()
                .append('path')

        d3.select('svg')
            .selectAll('line')
                .data([-5,-4,-3,-2,-1,0,1,2,3,4,5])
            .enter()
                .append('line')
                .attr('fill','none')
                .attr('stroke',d=>{
                    if(d==0) return 'red';
                    return 'blue'
                })
                .attr('strke-width',2)
                .attr('x1', scaleX(0))
                .attr('x2', scaleX(scaleX.domain()[1]))
                .attr('y1', d => scaleY(d))
                .attr('y2', d => scaleY(d));

        function update(){
            d3.select('path')
                .attr('fill','none')
                .attr('stroke','black')
                .attr('d', line);
        }

        update();
    </script>
</html>
	<!DOCTYPE html>
	<html lang="en">
	<head>
	<meta charset="UTF-8">
	<meta name="viewport" content="width=device-width, initial-scale=1.0">
	<meta http-equiv="X-UA-Compatible" content="ie=edge">
	<title>Test</title>
	<script src="https://d3js.org/d3.v5.min.js"></script>
	<script src="index.js"></script>
	</head>
	<body>
	<svg width="500" height="500"></svg>
	</body>
	<script>
	//default is that it oscilates between -1 and 1
	//with one complete oscilation hapening every 1 unit of time

	function makeSinOscilator(range=[-1,1], waveLength = 1){
	waveLength = waveLength/(2*Math.PI);
	const scaleX = d3.scaleLinear()
	.domain([-1,1])
	.range(range)

	return (time) => scaleX( Math.sin(time/waveLength) );
	}

	const myOsc = makeSinOscilator([-2,2],0.5);
	const values = [];

	for(let t = 0; t<1; t += 0.01){
	values.push({x:t, y:myOsc(t)});
	}

	const scaleX = d3.scaleLinear()
	.range([0,500])
	.domain(d3.extent(values, (d)=>d.x));

	const scaleY = d3.scaleLinear()
	.range([480,20])
	.domain([-5, 5]);

	const line = d3.line()
	.x(d => scaleX(d.x))
	.y(d => scaleY(d.y));

	d3.select('svg')
	.selectAll('path')
	.data([values])
	.enter()
	.append('path')

	d3.select('svg')
	.selectAll('line')
	.data([-5,-4,-3,-2,-1,0,1,2,3,4,5])
	.enter()
	.append('line')
	.attr('fill','none')
	.attr('stroke',d=>{
	if(d==0) return 'red';
	return 'blue'
	})
	.attr('strke-width',2)
	.attr('x1', scaleX(0))
	.attr('x2', scaleX(scaleX.domain()[1]))
	.attr('y1', d => scaleY(d))
	.attr('y2', d => scaleY(d));

	function update(){
	d3.select('path')
	.attr('fill','none')
	.attr('stroke','black')
	.attr('d', line);
	}

	update();
	</script>
	</html>