Published
Edited
Nov 19, 2020
md`# rotate shape`
width = 300
height = 300
o = [0, 0]
start = [300, 0]
md`## 正方形`
chart = {
let svg = d3.create('svg').attr("viewBox", [0, 0, width, height]);
let group = svg.append('g')
.attr('id', 'lines')
.attr('transform', `translate(${width/2}, ${height/2})`);
let PI = Math.PI;
let x = 100;
let y = 0;
for(let i = 0; i <= 3; i ++) {
for(let alpha = (2 * i - 1) * PI / 4 ; alpha < (PI / 4 * (i * 2 + 1)); alpha += offset_degree) {
if(i === 0) {
x = 100;
y = Math.tan(alpha) * x;
} else if(i === 1) {
y = 100;
x = y / Math.tan(alpha);
} else if(i === 2) {
x = -100;
y = Math.tan(alpha) * x;
} else if(i === 3) {
y = -100;
x = y / Math.tan(alpha);
}
group
.append("line")
.attr('x1', 0)
.attr('y1', 0)
.attr('x2', x)
.attr('y2', y)
// .attr('stroke', d3.interpolateRainbow(alpha * 2 / PI ))
.attr('stroke', 'steelblue')
.attr('stroke-width', 0.2);
}
}
return svg.node();
}
md`## 圆形`
chart1 = {
let svg = d3.create('svg').attr("viewBox", [0, 0, width, height]);
let group = svg.append('g')
.attr('id', 'lines')
.attr('transform', `translate(${width/2}, ${height/2})`);
let PI = Math.PI;
let w = 100;
let y = 0;
for(let i = 0; i <= 3; i ++) {
for(let alpha = (2 * i - 1) * PI / 4 ; alpha < (PI / 4 * (i * 2 + 1)); alpha += offset_degree) {
let x2 = Math.sin(alpha) * w;
let y2 = Math.cos(alpha) * w;
group
.append("line")
.attr('x1', 0)
.attr('y1', 0)
.attr('x2', x2)
.attr('y2', y2)
.attr('stroke', d3.interpolateRainbow(alpha / PI / 2 ))
// .attr('stroke', 'steelblue')
.attr('stroke-width', 0.2);
}
}
return svg.node();
}
md `# cos(cos(s))`
chart2 = {
let svg = d3.create('svg').attr("viewBox", [0, 0, width, height]);
let group = svg.append('g')
.attr('id', 'lines')
.attr('transform', `translate(${width/2}, ${height/2})`);
let PI = Math.PI;
let w = 100;
let y = 0;
for(let alpha = -PI; alpha < PI; alpha += offset_degree) {
let x2 = sin(sin(alpha / 10) * PI ) * w ;
let y2 = cos(cos(alpha * 2)) * w ;
group
.append("line")
.attr('x1', 0)
.attr('y1', 0)
.attr('x2', x2)
.attr('y2', y2)
.attr('stroke', d3.interpolateRainbow(alpha / PI / 2 ))
// .attr('stroke', 'steelblue')
.attr('stroke-width', 0.2);
}
return svg.node();
}
offset_degree = 0.005;
PI = Math.PI;
sin = Math.sin;
cos = Math.cos;
d3 = require('d3@5')
One platform to build and deploy the best data apps
Experiment and prototype by building visualizations in live JavaScript notebooks. Collaborate with your team and decide which concepts to build out.
Use Observable Framework to build data apps locally. Use data loaders to build in any language or library, including Python, SQL, and R.
Seamlessly deploy to Observable. Test before you ship, use automatic deploy-on-commit, and ensure your projects are always up-to-date.