chart2 = { const svg = d3.create("svg") .attr("viewBox", [0, 0, width, height]); svg.append("path") .datum(series1) .attr("fill", "none") .attr("stroke", "blue") .attr("stroke-width", 1) .attr("d", line); svg.append("circle") .attr("cx",x(loc_x)) .attr("cy",y(loc_y)) .attr("r",.4) .attr("fill",(loc_y>=0)? "green": "red"); svg.append("text") .text(loc_y.toFixed(4)) .attr("x",x(loc_x)) .attr("y",y(loc_y)) .attr("font-family","serif") .attr("font-size","8px") .attr("fill",(loc_y>=0)? "green": "red"); svg.append("line") .attr("x1", x(0)) //<<== change your code here .attr("y1", y(0)) .attr("x2", x(2*pi)) //<<== and here .attr("y2", y(0)) .style("stroke-width", 1) .style("stroke", "grey") svg.append("line") .attr("x1", x(0)) //<<== change your code here .attr("y1", y(1)) .attr("x2", x(2*pi)) //<<== and here .attr("y2", y(1)) .style("stroke-width", 1) .style("stroke", "grey") .style("fill", "none") .style("stroke-dasharray", ("3, 3")); svg.append("line") .attr("x1", x(0)) //<<== change your code here .attr("y1", y(-1)) .attr("x2", x(2*pi)) //<<== and here .attr("y2", y(-1)) .style("stroke-width", 1) .style("stroke", "grey") .style("fill", "none") .style("stroke-dasharray", ("3, 3")); // pi svg.append("circle") .attr("cx",x(pi)) .attr("cy",.5*(margin.top+height-margin.bottom)) .attr("r",2) .attr("fill","black") // pi/2 svg.append("circle") .attr("cx",x(pi/2)) .attr("cy",.5*(margin.top+height-margin.bottom)) .attr("r",2) .attr("fill","black") // 3*pi/2 svg.append("circle") .attr("cx",x(3*pi/2)) .attr("cy",.5*(margin.top+height-margin.bottom)) .attr("r",2) .attr("fill","black") // 2*pi svg.append("circle") .attr("cx",x(2*pi)) .attr("cy",.5*(margin.top+height-margin.bottom)) .attr("r",2) .attr("fill","black") // pi svg.append("text") .text("\u03C0") .attr("x",x(pi)-5) .attr("y",.5*(margin.top+height-margin.bottom)-5) .attr("font-family","serif") .attr("font-size","18px") // pi/2 svg.append("text") .text("\u03C0/2") .attr("x",x(pi/2)-10) .attr("y",.5*(margin.top+height-margin.bottom)-5) .attr("font-family","serif") .attr("font-size","18px") // 3*pi/2 svg.append("text") .text("3\u03C0/2") .attr("x",x(3*pi/2)-15) .attr("y",.5*(margin.top+height-margin.bottom)-5) .attr("font-family","serif") .attr("font-size","18px") // 2*pi svg.append("text") .text("2\u03C0") .attr("x",x(2*pi)-10) .attr("y",.5*(margin.top+height-margin.bottom)-5) .attr("font-family","serif") .attr("font-size","18px") return svg.node(); };