Force multiple y-axes to share the same scale

Hi all, I'm new to BIRT and to the community as well, so please bear with me as I struggle to figure this out.

I'm designing a cost and volume report with multiple charts, and they come from a central file with actual cost and volume, as well as the budgeted costs for the month.

So they are roughly in the form of

Month,Budgeted_Server,CPU_Hours_Server,Actual_Costs_Server,Budgeted_Email,...
1/12,500000,213,492099,10000,
2/12,500000,202,487000,10000,
so on, and so forth.

I have a number of charts made with, for example, the server costs for the ongoing year. I make a stacked bar chart with a secondary axis because I have several different types of servers and I have to add them up to compare it against the budget. I have x-axis to be the month, and set y-axis 1 to be sum of costs for all my different servers, and set y-axis 2 to be my projected budget.

Everything seems to go well until the actual chart rendering, the budget seems to be a lot lower than it's supposed to be, and further investigation shows that the two axes are not scaled the same. I have to go in and manually change the scale for both axes to the same minimum and maximum numbers for the graph to display accurately. However I'm always fearful of when a month comes and an abnormally high or low figure comes in, then I'll have to change the scales again.

Is there a setting that forces the two y-axes to have the same scale? A script would be fine as well, though I have little experience with scripting in BIRT so I may need a more in-depth walkthrough of that.

Thanks, appreciate it!

Find more posts tagged with

Comments

mwilliams

Is there a reason your're using two separate axes? If you go deselect the multiple axes option and go back to the "select data" tab of the chart wizard, you can add a second series by clicking the drop down by "series 1" and choose to add another series. This will put both series on the same axis. Maybe I'm over-simplifying your issue. Let me know!

Auroras

Sure, for example, if we separate our server assets into production, staging, test, etc., but we have one big server budget, then I would like to show the server asset costs in stacked bar form to show how much each type of server takes up as a part of the overall spending, and compare the entire stacked bar against the budget for the month. (Which is why I would like the budget to be in line form instead.)

mwilliams

If you just create a stacked bar chart and include your budget as a series in the bar chart, when you go to the format chart tab of the wizard, if you select the "Series" section, you can deselect the "stacked" option for your budget series and then choose line series from the drop down. This allows you to have a line chart on the same axis as the stacked bar chart, without doing any scripting to force two axes to have the same scale. If I'm still on the wrong track, let me know. An example, using a flat file of your data would be helpful in seeing the issue. Thanks!

Auroras

You are a **** and I love you.

That was exactly the answer I asked for, thank you.

mwilliams

You're welcome! Let us know whenever you have questions!

annblack

Hello -

I am trying to achieve something similar, but with a twist. I would like to show two different sets of stacked data, but with the same same y axis. I am trying to compare disk read/writes (stacked) against network send/received (stacked). I tried to use the technique above but when I change the series type to tube (from area) I can't change the 4th series to tube and stacked.

Any thoughts on how to acheive this? It would seem I could force the scales of both y axis, but I would rather not do that since then the chart is no longer truely dynamic.

Thanks much!