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diff --git a/jquery.flot.threshold.js b/jquery.flot.threshold.js
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+/*
+Flot plugin for thresholding data. Controlled through the option
+"threshold" in either the global series options
+
+  series: {
+    threshold: {
+      below: number
+      color: colorspec
+    }
+  }
+
+or in a specific series
+
+  $.plot($("#placeholder"), [{ data: [ ... ], threshold: { ... }}])
+
+The data points below "below" are drawn with the specified color. This
+makes it easy to mark points below 0, e.g. for budget data.
+
+Internally, the plugin works by splitting the data into two series,
+above and below the threshold. The extra series below the threshold
+will have its label cleared and the special "originSeries" attribute
+set to the original series. You may need to check for this in hover
+events.
+*/
+
+(function ($) {
+    var options = {
+        series: { threshold: null } // or { below: number, color: color spec}
+    };
+    
+    function init(plot) {
+        function thresholdData(plot, s, datapoints) {
+            if (!s.threshold)
+                return;
+            
+            var ps = datapoints.pointsize, i, x, y, p, prevp,
+                thresholded = $.extend({}, s); // note: shallow copy
+
+            thresholded.datapoints = { points: [], pointsize: ps };
+            thresholded.label = null;
+            thresholded.color = s.threshold.color;
+            thresholded.threshold = null;
+            thresholded.originSeries = s;
+            thresholded.data = [];
+
+            var below = s.threshold.below,
+                origpoints = datapoints.points,
+                addCrossingPoints = s.lines.show;
+
+            threspoints = [];
+            newpoints = [];
+
+            for (i = 0; i < origpoints.length; i += ps) {
+                x = origpoints[i]
+                y = origpoints[i + 1];
+
+                prevp = p;
+                if (y < below)
+                    p = threspoints;
+                else
+                    p = newpoints;
+
+                if (addCrossingPoints && prevp != p && x != null
+                    && i > 0 && origpoints[i - ps] != null) {
+                    var interx = (x - origpoints[i - ps]) / (y - origpoints[i - ps + 1]) * (below - y) + x;
+                    prevp.push(interx);
+                    prevp.push(below);
+                    for (m = 2; m < ps; ++m)
+                        prevp.push(origpoints[i + m]);
+                    
+                    p.push(null); // start new segment
+                    p.push(null);
+                    for (m = 2; m < ps; ++m)
+                        p.push(origpoints[i + m]);
+                    p.push(interx);
+                    p.push(below);
+                    for (m = 2; m < ps; ++m)
+                        p.push(origpoints[i + m]);
+                }
+
+                p.push(x);
+                p.push(y);
+            }
+
+            datapoints.points = newpoints;
+            thresholded.datapoints.points = threspoints;
+            
+            if (thresholded.datapoints.points.length > 0)
+                plot.getData().push(thresholded);
+                
+            // FIXME: there are probably some edge cases left in bars
+        }
+        
+        plot.hooks.processDatapoints.push(thresholdData);
+    }
+    
+    $.plot.plugins.push({
+        init: init,
+        options: options,
+        name: 'threshold',
+        version: '1.0'
+    });
+})(jQuery);