| /* Flot plugin for plotting error bars. |
| |
| Copyright (c) 2007-2014 IOLA and Ole Laursen. |
| Licensed under the MIT license. |
| |
| Error bars are used to show standard deviation and other statistical |
| properties in a plot. |
| |
| * Created by Rui Pereira - rui (dot) pereira (at) gmail (dot) com |
| |
| This plugin allows you to plot error-bars over points. Set "errorbars" inside |
| the points series to the axis name over which there will be error values in |
| your data array (*even* if you do not intend to plot them later, by setting |
| "show: null" on xerr/yerr). |
| |
| The plugin supports these options: |
| |
| series: { |
| points: { |
| errorbars: "x" or "y" or "xy", |
| xerr: { |
| show: null/false or true, |
| asymmetric: null/false or true, |
| upperCap: null or "-" or function, |
| lowerCap: null or "-" or function, |
| color: null or color, |
| radius: null or number |
| }, |
| yerr: { same options as xerr } |
| } |
| } |
| |
| Each data point array is expected to be of the type: |
| |
| "x" [ x, y, xerr ] |
| "y" [ x, y, yerr ] |
| "xy" [ x, y, xerr, yerr ] |
| |
| Where xerr becomes xerr_lower,xerr_upper for the asymmetric error case, and |
| equivalently for yerr. Eg., a datapoint for the "xy" case with symmetric |
| error-bars on X and asymmetric on Y would be: |
| |
| [ x, y, xerr, yerr_lower, yerr_upper ] |
| |
| By default no end caps are drawn. Setting upperCap and/or lowerCap to "-" will |
| draw a small cap perpendicular to the error bar. They can also be set to a |
| user-defined drawing function, with (ctx, x, y, radius) as parameters, as eg. |
| |
| function drawSemiCircle( ctx, x, y, radius ) { |
| ctx.beginPath(); |
| ctx.arc( x, y, radius, 0, Math.PI, false ); |
| ctx.moveTo( x - radius, y ); |
| ctx.lineTo( x + radius, y ); |
| ctx.stroke(); |
| } |
| |
| Color and radius both default to the same ones of the points series if not |
| set. The independent radius parameter on xerr/yerr is useful for the case when |
| we may want to add error-bars to a line, without showing the interconnecting |
| points (with radius: 0), and still showing end caps on the error-bars. |
| shadowSize and lineWidth are derived as well from the points series. |
| |
| */ |
| |
| (function ($) { |
| var options = { |
| series: { |
| points: { |
| errorbars: null, //should be 'x', 'y' or 'xy' |
| xerr: { err: 'x', show: null, asymmetric: null, upperCap: null, lowerCap: null, color: null, radius: null}, |
| yerr: { err: 'y', show: null, asymmetric: null, upperCap: null, lowerCap: null, color: null, radius: null} |
| } |
| } |
| }; |
| |
| function processRawData(plot, series, data, datapoints){ |
| if (!series.points.errorbars) |
| return; |
| |
| // x,y values |
| var format = [ |
| { x: true, number: true, required: true }, |
| { y: true, number: true, required: true } |
| ]; |
| |
| var errors = series.points.errorbars; |
| // error bars - first X then Y |
| if (errors == 'x' || errors == 'xy') { |
| // lower / upper error |
| if (series.points.xerr.asymmetric) { |
| format.push({ x: true, number: true, required: true }); |
| format.push({ x: true, number: true, required: true }); |
| } else |
| format.push({ x: true, number: true, required: true }); |
| } |
| if (errors == 'y' || errors == 'xy') { |
| // lower / upper error |
| if (series.points.yerr.asymmetric) { |
| format.push({ y: true, number: true, required: true }); |
| format.push({ y: true, number: true, required: true }); |
| } else |
| format.push({ y: true, number: true, required: true }); |
| } |
| datapoints.format = format; |
| } |
| |
| function parseErrors(series, i){ |
| |
| var points = series.datapoints.points; |
| |
| // read errors from points array |
| var exl = null, |
| exu = null, |
| eyl = null, |
| eyu = null; |
| var xerr = series.points.xerr, |
| yerr = series.points.yerr; |
| |
| var eb = series.points.errorbars; |
| // error bars - first X |
| if (eb == 'x' || eb == 'xy') { |
| if (xerr.asymmetric) { |
| exl = points[i + 2]; |
| exu = points[i + 3]; |
| if (eb == 'xy') |
| if (yerr.asymmetric){ |
| eyl = points[i + 4]; |
| eyu = points[i + 5]; |
| } else eyl = points[i + 4]; |
| } else { |
| exl = points[i + 2]; |
| if (eb == 'xy') |
| if (yerr.asymmetric) { |
| eyl = points[i + 3]; |
| eyu = points[i + 4]; |
| } else eyl = points[i + 3]; |
| } |
| // only Y |
| } else if (eb == 'y') |
| if (yerr.asymmetric) { |
| eyl = points[i + 2]; |
| eyu = points[i + 3]; |
| } else eyl = points[i + 2]; |
| |
| // symmetric errors? |
| if (exu == null) exu = exl; |
| if (eyu == null) eyu = eyl; |
| |
| var errRanges = [exl, exu, eyl, eyu]; |
| // nullify if not showing |
| if (!xerr.show){ |
| errRanges[0] = null; |
| errRanges[1] = null; |
| } |
| if (!yerr.show){ |
| errRanges[2] = null; |
| errRanges[3] = null; |
| } |
| return errRanges; |
| } |
| |
| function drawSeriesErrors(plot, ctx, s){ |
| |
| var points = s.datapoints.points, |
| ps = s.datapoints.pointsize, |
| ax = [s.xaxis, s.yaxis], |
| radius = s.points.radius, |
| err = [s.points.xerr, s.points.yerr]; |
| |
| //sanity check, in case some inverted axis hack is applied to flot |
| var invertX = false; |
| if (ax[0].p2c(ax[0].max) < ax[0].p2c(ax[0].min)) { |
| invertX = true; |
| var tmp = err[0].lowerCap; |
| err[0].lowerCap = err[0].upperCap; |
| err[0].upperCap = tmp; |
| } |
| |
| var invertY = false; |
| if (ax[1].p2c(ax[1].min) < ax[1].p2c(ax[1].max)) { |
| invertY = true; |
| var tmp = err[1].lowerCap; |
| err[1].lowerCap = err[1].upperCap; |
| err[1].upperCap = tmp; |
| } |
| |
| for (var i = 0; i < s.datapoints.points.length; i += ps) { |
| |
| //parse |
| var errRanges = parseErrors(s, i); |
| |
| //cycle xerr & yerr |
| for (var e = 0; e < err.length; e++){ |
| |
| var minmax = [ax[e].min, ax[e].max]; |
| |
| //draw this error? |
| if (errRanges[e * err.length]){ |
| |
| //data coordinates |
| var x = points[i], |
| y = points[i + 1]; |
| |
| //errorbar ranges |
| var upper = [x, y][e] + errRanges[e * err.length + 1], |
| lower = [x, y][e] - errRanges[e * err.length]; |
| |
| //points outside of the canvas |
| if (err[e].err == 'x') |
| if (y > ax[1].max || y < ax[1].min || upper < ax[0].min || lower > ax[0].max) |
| continue; |
| if (err[e].err == 'y') |
| if (x > ax[0].max || x < ax[0].min || upper < ax[1].min || lower > ax[1].max) |
| continue; |
| |
| // prevent errorbars getting out of the canvas |
| var drawUpper = true, |
| drawLower = true; |
| |
| if (upper > minmax[1]) { |
| drawUpper = false; |
| upper = minmax[1]; |
| } |
| if (lower < minmax[0]) { |
| drawLower = false; |
| lower = minmax[0]; |
| } |
| |
| //sanity check, in case some inverted axis hack is applied to flot |
| if ((err[e].err == 'x' && invertX) || (err[e].err == 'y' && invertY)) { |
| //swap coordinates |
| var tmp = lower; |
| lower = upper; |
| upper = tmp; |
| tmp = drawLower; |
| drawLower = drawUpper; |
| drawUpper = tmp; |
| tmp = minmax[0]; |
| minmax[0] = minmax[1]; |
| minmax[1] = tmp; |
| } |
| |
| // convert to pixels |
| x = ax[0].p2c(x), |
| y = ax[1].p2c(y), |
| upper = ax[e].p2c(upper); |
| lower = ax[e].p2c(lower); |
| minmax[0] = ax[e].p2c(minmax[0]); |
| minmax[1] = ax[e].p2c(minmax[1]); |
| |
| //same style as points by default |
| var lw = err[e].lineWidth ? err[e].lineWidth : s.points.lineWidth, |
| sw = s.points.shadowSize != null ? s.points.shadowSize : s.shadowSize; |
| |
| //shadow as for points |
| if (lw > 0 && sw > 0) { |
| var w = sw / 2; |
| ctx.lineWidth = w; |
| ctx.strokeStyle = "rgba(0,0,0,0.1)"; |
| drawError(ctx, err[e], x, y, upper, lower, drawUpper, drawLower, radius, w + w/2, minmax); |
| |
| ctx.strokeStyle = "rgba(0,0,0,0.2)"; |
| drawError(ctx, err[e], x, y, upper, lower, drawUpper, drawLower, radius, w/2, minmax); |
| } |
| |
| ctx.strokeStyle = err[e].color? err[e].color: s.color; |
| ctx.lineWidth = lw; |
| //draw it |
| drawError(ctx, err[e], x, y, upper, lower, drawUpper, drawLower, radius, 0, minmax); |
| } |
| } |
| } |
| } |
| |
| function drawError(ctx,err,x,y,upper,lower,drawUpper,drawLower,radius,offset,minmax){ |
| |
| //shadow offset |
| y += offset; |
| upper += offset; |
| lower += offset; |
| |
| // error bar - avoid plotting over circles |
| if (err.err == 'x'){ |
| if (upper > x + radius) drawPath(ctx, [[upper,y],[Math.max(x + radius,minmax[0]),y]]); |
| else drawUpper = false; |
| if (lower < x - radius) drawPath(ctx, [[Math.min(x - radius,minmax[1]),y],[lower,y]] ); |
| else drawLower = false; |
| } |
| else { |
| if (upper < y - radius) drawPath(ctx, [[x,upper],[x,Math.min(y - radius,minmax[0])]] ); |
| else drawUpper = false; |
| if (lower > y + radius) drawPath(ctx, [[x,Math.max(y + radius,minmax[1])],[x,lower]] ); |
| else drawLower = false; |
| } |
| |
| //internal radius value in errorbar, allows to plot radius 0 points and still keep proper sized caps |
| //this is a way to get errorbars on lines without visible connecting dots |
| radius = err.radius != null? err.radius: radius; |
| |
| // upper cap |
| if (drawUpper) { |
| if (err.upperCap == '-'){ |
| if (err.err=='x') drawPath(ctx, [[upper,y - radius],[upper,y + radius]] ); |
| else drawPath(ctx, [[x - radius,upper],[x + radius,upper]] ); |
| } else if ($.isFunction(err.upperCap)){ |
| if (err.err=='x') err.upperCap(ctx, upper, y, radius); |
| else err.upperCap(ctx, x, upper, radius); |
| } |
| } |
| // lower cap |
| if (drawLower) { |
| if (err.lowerCap == '-'){ |
| if (err.err=='x') drawPath(ctx, [[lower,y - radius],[lower,y + radius]] ); |
| else drawPath(ctx, [[x - radius,lower],[x + radius,lower]] ); |
| } else if ($.isFunction(err.lowerCap)){ |
| if (err.err=='x') err.lowerCap(ctx, lower, y, radius); |
| else err.lowerCap(ctx, x, lower, radius); |
| } |
| } |
| } |
| |
| function drawPath(ctx, pts){ |
| ctx.beginPath(); |
| ctx.moveTo(pts[0][0], pts[0][1]); |
| for (var p=1; p < pts.length; p++) |
| ctx.lineTo(pts[p][0], pts[p][1]); |
| ctx.stroke(); |
| } |
| |
| function draw(plot, ctx){ |
| var plotOffset = plot.getPlotOffset(); |
| |
| ctx.save(); |
| ctx.translate(plotOffset.left, plotOffset.top); |
| $.each(plot.getData(), function (i, s) { |
| if (s.points.errorbars && (s.points.xerr.show || s.points.yerr.show)) |
| drawSeriesErrors(plot, ctx, s); |
| }); |
| ctx.restore(); |
| } |
| |
| function init(plot) { |
| plot.hooks.processRawData.push(processRawData); |
| plot.hooks.draw.push(draw); |
| } |
| |
| $.plot.plugins.push({ |
| init: init, |
| options: options, |
| name: 'errorbars', |
| version: '1.0' |
| }); |
| })(jQuery); |
