@@@ -447,85 -448,6 +448,85 @@@ new Dygraph(el, data,
Where the error bars do not overlap, we can say with 95% confidence that the series differ. There is a better than 95% chance that Ichiro was a better hitter than his team as a whole in 2004, the year he won the batting title.
+
Determining Zoom
+
+
+ It is possible to detect whether a chart has been zoomed in either axis by the use of the isZoomed function.
+ If called with no argument, it will report whether either axis has been zoomed.
+ Alternatively it can be called with an argument of either 'x' or 'y' and it will report the status of just that axis.
+
+
+
Here's a simple example using drawCallback to display the various zoom states whenever the chart is zoomed:
This chart shows monthly closes of the Dow Jones Industrial Average, both in nominal and real (i.e. adjusted for inflation) dollars. The shaded areas show its monthly high and low. CPI values with a base from 1982-84 are used to adjust for inflation.
+ When this flag is passed along with either the dateWindow or valueRange options, the zoom flags are not changed to reflect a zoomed state.
+ This is primarily useful for when the display area of a chart is changed programmatically and also where manual zooming is allowed and use is made of the isZoomed method to determine this.
+
+ When set for a y-axis, the graph shows that axis in y-scale. Any values less than or equal
+ to zero are not displayed.
+
+ Not compatible with showZero, and ignores connectSeparatedPoints. Also, showing log scale
+ with valueRanges that are less than zero will result in an unviewable graph.
+
+
diff --combined dygraph.js
index 646159a,4a1cef2..b043d06
--- a/dygraph.js
+++ b/dygraph.js
@@@ -24,7 -24,6 +24,6 @@@
If the 'errorBars' option is set in the constructor, the input should be of
the form
-
Date,SeriesA,SeriesB,...
YYYYMMDD,A1,sigmaA1,B1,sigmaB1,...
YYYYMMDD,A2,sigmaA2,B2,sigmaB2,...
@@@ -79,6 -78,11 +78,11 @@@ Dygraph.DEFAULT_WIDTH = 480
Dygraph.DEFAULT_HEIGHT = 320;
Dygraph.AXIS_LINE_WIDTH = 0.3;
+ Dygraph.LOG_SCALE = 10;
+ Dygraph.LN_TEN = Math.log(Dygraph.LOG_SCALE);
+ Dygraph.log10 = function(x) {
+ return Math.log(x) / Dygraph.LN_TEN;
+ }
// Default attribute values.
Dygraph.DEFAULT_ATTRS = {
@@@ -114,7 -118,6 +118,6 @@@
delimiter: ',',
- logScale: false,
sigma: 2.0,
errorBars: false,
fractions: false,
@@@ -195,10 -198,6 +198,10 @@@ Dygraph.prototype.__init__ = function(d
this.is_initial_draw_ = true;
this.annotations_ = [];
+ // Zoomed indicators - These indicate when the graph has been zoomed and on what axis.
+ this.zoomed_x_ = false;
+ this.zoomed_y_ = false;
+
// Clear the div. This ensure that, if multiple dygraphs are passed the same
// div, then only one will be drawn.
div.innerHTML = "";
@@@ -261,14 -260,12 +264,20 @@@
this.start_();
};
- // axis is an optional parameter. Can be set to 'x' or 'y'.
++// Axis is an optional parameter. Can be set to 'x' or 'y'.
+Dygraph.prototype.isZoomed = function(axis) {
+ if (axis == null) return this.zoomed_x_ || this.zoomed_y_;
+ if (axis == 'x') return this.zoomed_x_;
+ if (axis == 'y') return this.zoomed_y_;
+ throw "axis parameter to Dygraph.isZoomed must be missing, 'x' or 'y'.";
+};
+
+ Dygraph.prototype.toString = function() {
+ var maindiv = this.maindiv_;
+ var id = (maindiv && maindiv.id) ? maindiv.id : maindiv
+ return "[Dygraph " + id + "]";
+ }
+
Dygraph.prototype.attr_ = function(name, seriesName) {
if (seriesName &&
typeof(this.user_attrs_[seriesName]) != 'undefined' &&
@@@ -368,46 -365,154 +377,154 @@@ Dygraph.prototype.yAxisRanges = functio
* If specified, do this conversion for the coordinate system of a particular
* axis. Uses the first axis by default.
* Returns a two-element array: [X, Y]
+ *
+ * Note: use toDomXCoord instead of toDomCoords(x, null) and use toDomYCoord
+ * instead of toDomCoords(null, y, axis).
*/
Dygraph.prototype.toDomCoords = function(x, y, axis) {
- var ret = [null, null];
+ return [ this.toDomXCoord(x), this.toDomYCoord(y, axis) ];
+ };
+
+ /**
+ * Convert from data x coordinates to canvas/div X coordinate.
+ * If specified, do this conversion for the coordinate system of a particular
+ * axis.
+ * Returns a single value or null if x is null.
+ */
+ Dygraph.prototype.toDomXCoord = function(x) {
+ if (x == null) {
+ return null;
+ };
+
var area = this.plotter_.area;
- if (x !== null) {
- var xRange = this.xAxisRange();
- ret[0] = area.x + (x - xRange[0]) / (xRange[1] - xRange[0]) * area.w;
- }
+ var xRange = this.xAxisRange();
+ return area.x + (x - xRange[0]) / (xRange[1] - xRange[0]) * area.w;
+ }
- if (y !== null) {
- var yRange = this.yAxisRange(axis);
- ret[1] = area.y + (yRange[1] - y) / (yRange[1] - yRange[0]) * area.h;
- }
+ /**
+ * Convert from data x coordinates to canvas/div Y coordinate and optional
+ * axis. Uses the first axis by default.
+ *
+ * returns a single value or null if y is null.
+ */
+ Dygraph.prototype.toDomYCoord = function(y, axis) {
+ var pct = this.toPercentYCoord(y, axis);
- return ret;
- };
+ if (pct == null) {
+ return null;
+ }
+ var area = this.plotter_.area;
+ return area.y + pct * area.h;
+ }
/**
* Convert from canvas/div coords to data coordinates.
* If specified, do this conversion for the coordinate system of a particular
* axis. Uses the first axis by default.
- * Returns a two-element array: [X, Y]
+ * Returns a two-element array: [X, Y].
+ *
+ * Note: use toDataXCoord instead of toDataCoords(x, null) and use toDataYCoord
+ * instead of toDataCoords(null, y, axis).
*/
Dygraph.prototype.toDataCoords = function(x, y, axis) {
- var ret = [null, null];
- var area = this.plotter_.area;
- if (x !== null) {
- var xRange = this.xAxisRange();
- ret[0] = xRange[0] + (x - area.x) / area.w * (xRange[1] - xRange[0]);
+ return [ this.toDataXCoord(x), this.toDataYCoord(y, axis) ];
+ };
+
+ /**
+ * Convert from canvas/div x coordinate to data coordinate.
+ *
+ * If x is null, this returns null.
+ */
+ Dygraph.prototype.toDataXCoord = function(x) {
+ if (x == null) {
+ return null;
}
- if (y !== null) {
- var yRange = this.yAxisRange(axis);
- ret[1] = yRange[0] + (area.h - y) / area.h * (yRange[1] - yRange[0]);
+ var area = this.plotter_.area;
+ var xRange = this.xAxisRange();
+ return xRange[0] + (x - area.x) / area.w * (xRange[1] - xRange[0]);
+ };
+
+ /**
+ * Convert from canvas/div y coord to value.
+ *
+ * If y is null, this returns null.
+ * if axis is null, this uses the first axis.
+ */
+ Dygraph.prototype.toDataYCoord = function(y, axis) {
+ if (y == null) {
+ return null;
}
- return ret;
+ var area = this.plotter_.area;
+ var yRange = this.yAxisRange(axis);
+
+ if (typeof(axis) == "undefined") axis = 0;
+ if (!this.axes_[axis].logscale) {
+ return yRange[0] + (area.h - y) / area.h * (yRange[1] - yRange[0]);
+ } else {
+ // Computing the inverse of toDomCoord.
+ var pct = (y - area.y) / area.h
+
+ // Computing the inverse of toPercentYCoord. The function was arrived at with
+ // the following steps:
+ //
+ // Original calcuation:
+ // pct = (logr1 - Dygraph.log10(y)) / (logr1 - Dygraph.log10(yRange[0]));
+ //
+ // Move denominator to both sides:
+ // pct * (logr1 - Dygraph.log10(yRange[0])) = logr1 - Dygraph.log10(y);
+ //
+ // subtract logr1, and take the negative value.
+ // logr1 - (pct * (logr1 - Dygraph.log10(yRange[0]))) = Dygraph.log10(y);
+ //
+ // Swap both sides of the equation, and we can compute the log of the
+ // return value. Which means we just need to use that as the exponent in
+ // e^exponent.
+ // Dygraph.log10(y) = logr1 - (pct * (logr1 - Dygraph.log10(yRange[0])));
+
+ var logr1 = Dygraph.log10(yRange[1]);
+ var exponent = logr1 - (pct * (logr1 - Dygraph.log10(yRange[0])));
+ var value = Math.pow(Dygraph.LOG_SCALE, exponent);
+ return value;
+ }
};
/**
+ * Converts a y for an axis to a percentage from the top to the
+ * bottom of the div.
+ *
+ * If the coordinate represents a value visible on the canvas, then
+ * the value will be between 0 and 1, where 0 is the top of the canvas.
+ * However, this method will return values outside the range, as
+ * values can fall outside the canvas.
+ *
+ * If y is null, this returns null.
+ * if axis is null, this uses the first axis.
+ */
+ Dygraph.prototype.toPercentYCoord = function(y, axis) {
+ if (y == null) {
+ return null;
+ }
+ if (typeof(axis) == "undefined") axis = 0;
+
+ var area = this.plotter_.area;
+ var yRange = this.yAxisRange(axis);
+
+ var pct;
+ if (!this.axes_[axis].logscale) {
+ // yrange[1] - y is unit distance from the bottom.
+ // yrange[1] - yrange[0] is the scale of the range.
+ // (yRange[1] - y) / (yRange[1] - yRange[0]) is the % from the bottom.
+ pct = (yRange[1] - y) / (yRange[1] - yRange[0]);
+ } else {
+ var logr1 = Dygraph.log10(yRange[1]);
+ pct = (logr1 - Dygraph.log10(y)) / (logr1 - Dygraph.log10(yRange[0]));
+ }
+ return pct;
+ }
+
+ /**
* Returns the number of columns (including the independent variable).
*/
Dygraph.prototype.numColumns = function() {
@@@ -823,9 -928,17 +940,17 @@@ Dygraph.startPan = function(event, g, c
var axis = g.axes_[i];
var yRange = g.yAxisRange(i);
// TODO(konigsberg): These values should be in |context|.
- axis.dragValueRange = yRange[1] - yRange[0];
- axis.initialTopValue = yRange[1];
+ // In log scale, initialTopValue, dragValueRange and unitsPerPixel are log scale.
+ if (axis.logscale) {
+ axis.initialTopValue = Dygraph.log10(yRange[1]);
+ axis.dragValueRange = Dygraph.log10(yRange[1]) - Dygraph.log10(yRange[0]);
+ } else {
+ axis.initialTopValue = yRange[1];
+ axis.dragValueRange = yRange[1] - yRange[0];
+ }
axis.unitsPerPixel = axis.dragValueRange / (g.plotter_.area.h - 1);
+
+ // While calculating axes, set 2dpan.
if (axis.valueWindow || axis.valueRange) context.is2DPan = true;
}
};
@@@ -851,10 -964,19 +976,19 @@@ Dygraph.movePan = function(event, g, co
// Adjust each axis appropriately.
for (var i = 0; i < g.axes_.length; i++) {
var axis = g.axes_[i];
- var maxValue = axis.initialTopValue +
- (context.dragEndY - context.dragStartY) * axis.unitsPerPixel;
+
+ var pixelsDragged = context.dragEndY - context.dragStartY;
+ var unitsDragged = pixelsDragged * axis.unitsPerPixel;
+
+ // In log scale, maxValue and minValue are the logs of those values.
+ var maxValue = axis.initialTopValue + unitsDragged;
var minValue = maxValue - axis.dragValueRange;
- axis.valueWindow = [ minValue, maxValue ];
+ if (axis.logscale) {
+ axis.valueWindow = [ Math.pow(Dygraph.LOG_SCALE, minValue),
+ Math.pow(Dygraph.LOG_SCALE, maxValue) ];
+ } else {
+ axis.valueWindow = [ minValue, maxValue ];
+ }
}
}
@@@ -1186,10 -1308,8 +1320,8 @@@ Dygraph.prototype.drawZoomRect_ = funct
Dygraph.prototype.doZoomX_ = function(lowX, highX) {
// Find the earliest and latest dates contained in this canvasx range.
// Convert the call to date ranges of the raw data.
- var r = this.toDataCoords(lowX, null);
- var minDate = r[0];
- r = this.toDataCoords(highX, null);
- var maxDate = r[0];
+ var minDate = this.toDataXCoord(lowX);
+ var maxDate = this.toDataXCoord(highX);
this.doZoomXDates_(minDate, maxDate);
};
@@@ -1204,7 -1324,6 +1336,7 @@@
*/
Dygraph.prototype.doZoomXDates_ = function(minDate, maxDate) {
this.dateWindow_ = [minDate, maxDate];
+ this.zoomed_x_ = true;
this.drawGraph_();
if (this.attr_("zoomCallback")) {
this.attr_("zoomCallback")(minDate, maxDate, this.yAxisRanges());
@@@ -1226,17 -1345,15 +1358,17 @@@ Dygraph.prototype.doZoomY_ = function(l
// coordinates increase as you go up the screen.
var valueRanges = [];
for (var i = 0; i < this.axes_.length; i++) {
- var hi = this.toDataCoords(null, lowY, i);
- var low = this.toDataCoords(null, highY, i);
- this.axes_[i].valueWindow = [low[1], hi[1]];
- valueRanges.push([low[1], hi[1]]);
+ var hi = this.toDataYCoord(lowY, i);
+ var low = this.toDataYCoord(highY, i);
+ this.axes_[i].valueWindow = [low, hi];
+ valueRanges.push([low, hi]);
}
+ this.zoomed_y_ = true;
this.drawGraph_();
if (this.attr_("zoomCallback")) {
var xRange = this.xAxisRange();
+ var yRange = this.yAxisRange();
this.attr_("zoomCallback")(xRange[0], xRange[1], this.yAxisRanges());
}
};
@@@ -1264,8 -1381,6 +1396,8 @@@ Dygraph.prototype.doUnzoom_ = function(
if (dirty) {
// Putting the drawing operation before the callback because it resets
// yAxisRange.
+ this.zoomed_x_ = false;
+ this.zoomed_y_ = false;
this.drawGraph_();
if (this.attr_("zoomCallback")) {
var minDate = this.rawData_[0][0];
@@@ -1302,10 -1417,6 +1434,6 @@@ Dygraph.prototype.mouseMove_ = function
idx = i;
}
if (idx >= 0) lastx = points[idx].xval;
- // Check that you can really highlight the last day's data
- var last = points[points.length-1];
- if (last != null && canvasx > last.canvasx)
- lastx = points[points.length-1].xval;
// Extract the points we've selected
this.selPoints_ = [];
@@@ -1813,10 -1924,75 +1941,75 @@@ Dygraph.dateTicker = function(startDate
}
};
+ // 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:
+ // ..., 1, 2, 3, 4, 5, ..., 9, 10, 20, 30, ..., 90, 100, 200, 300, ...
+ // NOTE: this assumes that Dygraph.LOG_SCALE = 10.
+ Dygraph.PREFERRED_LOG_TICK_VALUES = function() {
+ var vals = [];
+ for (var power = -39; power <= 39; power++) {
+ var range = Math.pow(10, power);
+ for (var mult = 1; mult <= 9; mult++) {
+ var val = range * mult;
+ vals.push(val);
+ }
+ }
+ return vals;
+ }();
+
+ // val is the value to search for
+ // arry is the value over which to search
+ // if abs > 0, find the lowest entry greater than val
+ // if abs < 0, find the highest entry less than val
+ // if abs == 0, find the entry that equals val.
+ // Currently does not work when val is outside the range of arry's values.
+ Dygraph.binarySearch = function(val, arry, abs, low, high) {
+ if (low == null || high == null) {
+ low = 0;
+ high = arry.length - 1;
+ }
+ if (low > high) {
+ return -1;
+ }
+ if (abs == null) {
+ abs = 0;
+ }
+ var validIndex = function(idx) {
+ return idx >= 0 && idx < arry.length;
+ }
+ var mid = parseInt((low + high) / 2);
+ var element = arry[mid];
+ if (element == val) {
+ return mid;
+ }
+ if (element > val) {
+ if (abs > 0) {
+ // Accept if element > val, but also if prior element < val.
+ var idx = mid - 1;
+ if (validIndex(idx) && arry[idx] < val) {
+ return mid;
+ }
+ }
+ return Dygraph.binarySearch(val, arry, abs, low, mid - 1);
+ }
+ if (element < val) {
+ if (abs < 0) {
+ // Accept if element < val, but also if prior element > val.
+ var idx = mid + 1;
+ if (validIndex(idx) && arry[idx] > val) {
+ return mid;
+ }
+ }
+ return Dygraph.binarySearch(val, arry, abs, mid + 1, high);
+ }
+ };
+
/**
* Add ticks when the x axis has numbers on it (instead of dates)
- * @param {Number} startDate Start of the date window (millis since epoch)
- * @param {Number} endDate End of the date window (millis since epoch)
+ * TODO(konigsberg): Update comment.
+ *
+ * @param {Number} minV minimum value
+ * @param {Number} maxV maximum value
* @param self
* @param {function} attribute accessor function.
* @return {Array.