Google bar chart: moving zero axis up, painting negative valuse red

Question

I have the following chart for displaying "virtual money" in a weekly game tournament (player money is dark blue, compared to best player money values in light blue):

http://chart.apis.google.com/chart?chs=700x280&cht=bvo&chco=4D89F9,C6D9FD&chd=t:713,-647,-1202,-1830|3927,6133,8053,2576&chxl=0:|2010-44|2010-45|2010-46|2010-47&chxt=x,y&chxr=1,-1830,8053&chds=-1830,8053&chbh=140&chm=N,,0,,12|N,,1,,12

1) Is there please a way to the X-axis up a bit, so that the negative dark blue bars appear below it?

2) Is there a way to append a "$" to the values (instead of prepending with cUSD)?

3) Is there a way to paint only negative values red? Can't find this in the doc, I only see how to make them all red with N,FF0000,0,,12

Thank you! Alex

Answer 1

The zero line can be added as horizontal marker line going through y=0, you'll still get the odd 'x-axis' on the bottom of the graph, but this was acceptable for me at least.

Just add an additional data series chd=[your data]|0 and an additional marker chm=[your markers]|H,000000,2,1,1 [ H=horizontal line, 000000=hexadecimal for black, 2=the index of the last data series, 1=width of 1px, 1=z-index of 1 (in front of stacked bars) ]

so the final chart looks like this:

PS: I know this is a rather old question and you have probably moved on, but I came accross this question when I myself was looking for answers to 1) and 3), Nick's answer took care of 3) [thanks Nick] but 1) wasn't answered. So this is just for anyone else stumbling accross this question as I did.

Answer 2

You can only list the individual dataset colors with chco, so you can certainly make the bottom dataset red (as you've done with the blue), but not just the negative members. My suggestion for making the negative members red is making a 3rd negative data set overlapping the positive data set, where the values are _ when they're not negative so you don't draw a bar (_ or __ indicates a missing value, depending on your encoding type). You'd have something like:

chd=t:713,_,_,_|_,-647,-1202,-1830|3927,6133,8053,2576
chco=4D89F9,FF0000,C6D9FD

You'll probably have to play with the ordering a bit and the data style attributes in order to get the colors and labels to be the way you want them.

As far as I know there's no way to move the X axis up to zero on the chart (it can only go on either top or bottom), but you can make it invisible (while still leaving the labels) using chxs, which might give you a better look.

Answer 3

I've managed to append $ with N**$