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