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Frequently asked questions |
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Q: How much data can Flot cope with? |
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A: Flot will happily draw everything you send to it so the answer |
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depends on the browser. The excanvas emulation used for IE (built with |
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VML) makes IE by far the slowest browser so be sure to test with that |
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if IE users are in your target group. |
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1000 points is not a problem, but as soon as you start having more |
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points than the pixel width, you should probably start thinking about |
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downsampling/aggregation as this is near the resolution limit of the |
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chart anyway. If you downsample server-side, you also save bandwidth. |
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Q: Flot isn't working when I'm using JSON data as source! |
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A: Actually, Flot loves JSON data, you just got the format wrong. |
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Double check that you're not inputting strings instead of numbers, |
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like [["0", "-2.13"], ["5", "4.3"]]. This is most common mistake, and |
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the error might not show up immediately because Javascript can do some |
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conversion automatically. |
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Q: Can I export the graph? |
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A: This is a limitation of the canvas technology. There's a hook in |
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the canvas object for getting an image out, but you won't get the tick |
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labels. And it's not likely to be supported by IE. At this point, your |
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best bet is probably taking a screenshot, e.g. with PrtScn. |
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Q: The bars are all tiny in time mode? |
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A: It's not really possible to determine the bar width automatically. |
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So you have to set the width with the barWidth option which is NOT in |
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pixels, but in the units of the x axis (or the y axis for horizontal |
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bars). For time mode that's milliseconds so the default value of 1 |
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makes the bars 1 millisecond wide. |
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Q: Can I use Flot with libraries like Mootools or Prototype? |
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A: Yes, Flot supports it out of the box and it's easy! Just use jQuery |
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instead of $, e.g. call jQuery.plot instead of $.plot and use |
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jQuery(something) instead of $(something). As a convenience, you can |
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put in a DOM element for the graph placeholder where the examples and |
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the API documentation are using jQuery objects. |
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Depending on how you include jQuery, you may have to add one line of |
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code to prevent jQuery from overwriting functions from the other |
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libraries, see the documentation in jQuery ("Using jQuery with other |
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libraries") for details. |
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Q: Flot doesn't work with [insert name of Javascript UI framework]! |
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A: The only non-standard thing used by Flot is the canvas tag; |
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otherwise it is simply a series of absolute positioned divs within the |
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placeholder tag you put in. If this is not working, it's probably |
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because the framework you're using is doing something weird with the |
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DOM, or you're using it the wrong way. |
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A common problem is that there's display:none on a container until the |
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user does something. Many tab widgets work this way, and there's |
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nothing wrong with it - you just can't call Flot inside a display:none |
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container as explained in the README so you need to hold off the Flot |
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call until the container is actually displayed (or use |
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visibility:hidden instead of display:none or move the container |
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off-screen). |
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If you find there's a specific thing we can do to Flot to help, feel |
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free to submit a bug report. Otherwise, you're welcome to ask for help |
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on the forum/mailing list, but please don't submit a bug report to |
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Flot. |
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