X-Git-Url: https://adrianiainlam.tk/git/?a=blobdiff_plain;f=dygraph-tickers.js;h=f4778b12b7a3ddc918bcafcc61800bbe914809c3;hb=87f2fcd1862a6142c3535612a4679e6fc865baf4;hp=b340626696195692d4f9fdfc126f0586b7f8e052;hpb=36a27704957dda706074a857884d52c1cf5a974c;p=dygraphs.git diff --git a/dygraph-tickers.js b/dygraph-tickers.js index b340626..f4778b1 100644 --- a/dygraph-tickers.js +++ b/dygraph-tickers.js @@ -58,12 +58,12 @@ * middle of the years. */ -/*jshint globalstrict: true */ +/*jshint globalstrict:true, sub:true */ /*global Dygraph:false */ "use strict"; /** @typedef {Array.<{v:number, label:string, label_v:(string|undefined)}>} */ -Dygraph.TickList; +Dygraph.TickList = undefined; // the ' = undefined' keeps jshint happy. /** @typedef {function( * number, @@ -74,8 +74,7 @@ Dygraph.TickList; * Array.= * ): Dygraph.TickList} */ -Dygraph.Ticker; - +Dygraph.Ticker = undefined; // the ' = undefined' keeps jshint happy. /** @type {Dygraph.Ticker} */ Dygraph.numericLinearTicks = function(a, b, pixels, opts, dygraph, vals) { @@ -88,16 +87,6 @@ Dygraph.numericLinearTicks = function(a, b, pixels, opts, dygraph, vals) { /** @type {Dygraph.Ticker} */ Dygraph.numericTicks = function(a, b, pixels, opts, dygraph, vals) { - // This masks some numeric issues in older versions of Firefox, - // where 1.0/Math.pow(10,2) != Math.pow(10,-2). - /** @type {function(number,number):number} */ - var pow = function(base, exp) { - if (exp < 0) { - return 1.0 / Math.pow(base, -exp); - } - return Math.pow(base, exp); - }; - var pixels_per_tick = /** @type{number} */(opts('pixelsPerLabel')); var ticks = []; var i, j, tickV, nTicks; @@ -155,30 +144,40 @@ Dygraph.numericTicks = function(a, b, pixels, opts, dygraph, vals) { // The first spacing greater than pixelsPerYLabel is what we use. // TODO(danvk): version that works on a log scale. var kmg2 = opts("labelsKMG2"); - var mults; + var mults, base; if (kmg2) { - mults = [1, 2, 4, 8]; + mults = [1, 2, 4, 8, 16, 32, 64, 128, 256]; + base = 16; } else { - mults = [1, 2, 5]; + mults = [1, 2, 5, 10, 20, 50, 100]; + base = 10; } - var scale, low_val, high_val; - for (i = -10; i < 50; i++) { - var base_scale; - if (kmg2) { - base_scale = pow(16, i); - } else { - base_scale = pow(10, i); - } - var spacing = 0; - for (j = 0; j < mults.length; j++) { - scale = base_scale * mults[j]; - low_val = Math.floor(a / scale) * scale; - high_val = Math.ceil(b / scale) * scale; - nTicks = Math.abs(high_val - low_val) / scale; - spacing = pixels / nTicks; - // wish I could break out of both loops at once... - if (spacing > pixels_per_tick) break; - } + + // Get the maximum number of permitted ticks based on the + // graph's pixel size and pixels_per_tick setting. + var max_ticks = Math.ceil(pixels / pixels_per_tick); + + // Now calculate the data unit equivalent of this tick spacing. + // Use abs() since graphs may have a reversed Y axis. + var units_per_tick = Math.abs(b - a) / max_ticks; + + // Based on this, get a starting scale which is the largest + // integer power of the chosen base (10 or 16) that still remains + // below the requested pixels_per_tick spacing. + var base_power = Math.floor(Math.log(units_per_tick) / Math.log(base)); + var base_scale = Math.pow(base, base_power); + + // Now try multiples of the starting scale until we find one + // that results in tick marks spaced sufficiently far apart. + // The "mults" array should cover the range 1 .. base^2 to + // adjust for rounding and edge effects. + var scale, low_val, high_val, spacing; + for (j = 0; j < mults.length; j++) { + scale = base_scale * mults[j]; + low_val = Math.floor(a / scale) * scale; + high_val = Math.ceil(b / scale) * scale; + nTicks = Math.abs(high_val - low_val) / scale; + spacing = pixels / nTicks; if (spacing > pixels_per_tick) break; } @@ -192,58 +191,13 @@ Dygraph.numericTicks = function(a, b, pixels, opts, dygraph, vals) { } } - // Add formatted labels to the ticks. - var k; - var k_labels = []; - var m_labels = []; - if (opts("labelsKMB")) { - k = 1000; - k_labels = [ "K", "M", "B", "T", "Q" ]; - } - if (opts("labelsKMG2")) { - if (k) Dygraph.warn("Setting both labelsKMB and labelsKMG2. Pick one!"); - k = 1024; - k_labels = [ "k", "M", "G", "T", "P", "E", "Z", "Y" ]; - m_labels = [ "m", "u", "n", "p", "f", "a", "z", "y" ]; - } - - k = k || 1; // If neither option is specified. - var formatter = /**@type{AxisLabelFormatter}*/(opts('axisLabelFormatter')); // Add labels to the ticks. - var digitsAfterDecimal = /** @type{number} */(opts('digitsAfterDecimal')); for (i = 0; i < ticks.length; i++) { if (ticks[i].label !== undefined) continue; // Use current label. - tickV = ticks[i].v; - var absTickV = Math.abs(tickV); // TODO(danvk): set granularity to something appropriate here. - var label = formatter(tickV, 0, opts, dygraph); - if (k_labels.length > 0) { - // TODO(danvk): should this be integrated into the axisLabelFormatter? - // Round up to an appropriate unit. - var n = pow(k, k_labels.length); - for (j = k_labels.length - 1; j >= 0; j--, n /= k) { - if (absTickV >= n) { - label = Dygraph.round_(tickV / n, digitsAfterDecimal) + k_labels[j]; - break; - } - } - } - if(opts("labelsKMG2")){ - tickV = String(tickV.toExponential()); - if(tickV.split('e-').length === 2 && tickV.split('e-')[1] >= 3 && tickV.split('e-')[1] <= 24){ - if(tickV.split('e-')[1] % 3 > 0) { - label = Dygraph.round_(tickV.split('e-')[0] / - pow(10,(tickV.split('e-')[1] % 3)), - digitsAfterDecimal); - } else { - label = Number(tickV.split('e-')[0]).toFixed(2); - } - label += m_labels[Math.floor(tickV.split('e-')[1] / 3) - 1]; - } - } - ticks[i].label = label; + ticks[i].label = formatter(ticks[i].v, 0, opts, dygraph); } return ticks; @@ -305,6 +259,39 @@ Dygraph.SHORT_SPACINGS[Dygraph.SIX_HOURLY] = 1000 * 3600 * 6; Dygraph.SHORT_SPACINGS[Dygraph.DAILY] = 1000 * 86400; Dygraph.SHORT_SPACINGS[Dygraph.WEEKLY] = 1000 * 604800; +/** + * A collection of objects specifying where it is acceptable to place tick + * marks for granularities larger than WEEKLY. + * 'months' is an array of month indexes on which to place tick marks. + * 'year_mod' ticks are placed when year % year_mod = 0. + * @type {Array.} + */ +Dygraph.LONG_TICK_PLACEMENTS = []; +Dygraph.LONG_TICK_PLACEMENTS[Dygraph.MONTHLY] = { + months : [0,1,2,3,4,5,6,7,8,9,10,11], + year_mod : 1 +}; +Dygraph.LONG_TICK_PLACEMENTS[Dygraph.QUARTERLY] = { + months: [0,3,6,9], + year_mod: 1 +}; +Dygraph.LONG_TICK_PLACEMENTS[Dygraph.BIANNUAL] = { + months: [0,6], + year_mod: 1 +}; +Dygraph.LONG_TICK_PLACEMENTS[Dygraph.ANNUAL] = { + months: [0], + year_mod: 1 +}; +Dygraph.LONG_TICK_PLACEMENTS[Dygraph.DECADAL] = { + months: [0], + year_mod: 10 +}; +Dygraph.LONG_TICK_PLACEMENTS[Dygraph.CENTENNIAL] = { + months: [0], + year_mod: 100 +}; + /** * This is a list of human-friendly values at which to show tick marks on a log * scale. It is k * 10^n, where k=1..9 and n=-39..+39, so: @@ -358,17 +345,11 @@ Dygraph.numDateTicks = function(start_time, end_time, granularity) { var spacing = Dygraph.SHORT_SPACINGS[granularity]; return Math.floor(0.5 + 1.0 * (end_time - start_time) / spacing); } else { - var year_mod = 1; // e.g. to only print one point every 10 years. - var num_months = 12; - if (granularity == Dygraph.QUARTERLY) num_months = 3; - if (granularity == Dygraph.BIANNUAL) num_months = 2; - if (granularity == Dygraph.ANNUAL) num_months = 1; - if (granularity == Dygraph.DECADAL) { num_months = 1; year_mod = 10; } - if (granularity == Dygraph.CENTENNIAL) { num_months = 1; year_mod = 100; } + var tickPlacement = Dygraph.LONG_TICK_PLACEMENTS[granularity]; var msInYear = 365.2524 * 24 * 3600 * 1000; var num_years = 1.0 * (end_time - start_time) / msInYear; - return Math.floor(0.5 + 1.0 * num_years * num_months / year_mod); + return Math.floor(0.5 + 1.0 * num_years * tickPlacement.months.length / tickPlacement.year_mod); } }; @@ -394,21 +375,25 @@ Dygraph.getDateAxis = function(start_time, end_time, granularity, opts, dg) { // for this granularity. var g = spacing / 1000; var d = new Date(start_time); - d.setMilliseconds(0); + Dygraph.setDateSameTZ(d, {ms: 0}); + var x; if (g <= 60) { // seconds - x = d.getSeconds(); d.setSeconds(x - x % g); + x = d.getSeconds(); + Dygraph.setDateSameTZ(d, {s: x - x % g}); } else { - d.setSeconds(0); + Dygraph.setDateSameTZ(d, {s: 0}); g /= 60; if (g <= 60) { // minutes - x = d.getMinutes(); d.setMinutes(x - x % g); + x = d.getMinutes(); + Dygraph.setDateSameTZ(d, {m: x - x % g}); } else { - d.setMinutes(0); + Dygraph.setDateSameTZ(d, {m: 0}); g /= 60; if (g <= 24) { // days - x = d.getHours(); d.setHours(x - x % g); + x = d.getHours(); + d.setHours(x - x % g); } else { d.setHours(0); g /= 24; @@ -421,9 +406,38 @@ Dygraph.getDateAxis = function(start_time, end_time, granularity, opts, dg) { } start_time = d.getTime(); + // For spacings coarser than two-hourly, we want to ignore daylight + // savings transitions to get consistent ticks. For finer-grained ticks, + // it's essential to show the DST transition in all its messiness. + var start_offset_min = new Date(start_time).getTimezoneOffset(); + var check_dst = (spacing >= Dygraph.SHORT_SPACINGS[Dygraph.TWO_HOURLY]); + for (t = start_time; t <= end_time; t += spacing) { + d = new Date(t); + + // This ensures that we stay on the same hourly "rhythm" across + // daylight savings transitions. Without this, the ticks could get off + // by an hour. See tests/daylight-savings.html or issue 147. + if (check_dst && d.getTimezoneOffset() != start_offset_min) { + var delta_min = d.getTimezoneOffset() - start_offset_min; + t += delta_min * 60 * 1000; + d = new Date(t); + start_offset_min = d.getTimezoneOffset(); + + // Check whether we've backed into the previous timezone again. + // This can happen during a "spring forward" transition. In this case, + // it's best to skip this tick altogether (we may be shooting for a + // non-existent time like the 2AM that's skipped) and go to the next + // one. + if (new Date(t + spacing).getTimezoneOffset() != start_offset_min) { + t += spacing; + d = new Date(t); + start_offset_min = d.getTimezoneOffset(); + } + } + ticks.push({ v:t, - label: formatter(new Date(t), granularity, opts, dg) + label: formatter(d, granularity, opts, dg) }); } } else { @@ -433,20 +447,9 @@ Dygraph.getDateAxis = function(start_time, end_time, granularity, opts, dg) { var months; var year_mod = 1; // e.g. to only print one point every 10 years. - if (granularity == Dygraph.MONTHLY) { - months = [ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 ]; - } else if (granularity == Dygraph.QUARTERLY) { - months = [ 0, 3, 6, 9 ]; - } else if (granularity == Dygraph.BIANNUAL) { - months = [ 0, 6 ]; - } else if (granularity == Dygraph.ANNUAL) { - months = [ 0 ]; - } else if (granularity == Dygraph.DECADAL) { - months = [ 0 ]; - year_mod = 10; - } else if (granularity == Dygraph.CENTENNIAL) { - months = [ 0 ]; - year_mod = 100; + if (granularity < Dygraph.NUM_GRANULARITIES) { + months = Dygraph.LONG_TICK_PLACEMENTS[granularity].months; + year_mod = Dygraph.LONG_TICK_PLACEMENTS[granularity].year_mod; } else { Dygraph.warn("Span of dates is too long"); } @@ -470,7 +473,15 @@ Dygraph.getDateAxis = function(start_time, end_time, granularity, opts, dg) { return ticks; }; -// These are set here so that this file can be included after dygraph.js. -Dygraph.DEFAULT_ATTRS['axes']['x']['ticker'] = Dygraph.dateTicker; -Dygraph.DEFAULT_ATTRS['axes']['y']['ticker'] = Dygraph.numericTicks; -Dygraph.DEFAULT_ATTRS['axes']['y2']['ticker'] = Dygraph.numericTicks; +// These are set here so that this file can be included after dygraph.js +// or independently. +if (Dygraph && + Dygraph.DEFAULT_ATTRS && + Dygraph.DEFAULT_ATTRS['axes'] && + Dygraph.DEFAULT_ATTRS['axes']['x'] && + Dygraph.DEFAULT_ATTRS['axes']['y'] && + Dygraph.DEFAULT_ATTRS['axes']['y2']) { + Dygraph.DEFAULT_ATTRS['axes']['x']['ticker'] = Dygraph.dateTicker; + Dygraph.DEFAULT_ATTRS['axes']['y']['ticker'] = Dygraph.numericTicks; + Dygraph.DEFAULT_ATTRS['axes']['y2']['ticker'] = Dygraph.numericTicks; +}