Chart : Force the X-Axis to start at Y=0

You can set the scale in the chart editor to 0, however, this will not work for you if you have negative numbers. One thing you could do would be to hide the x-axis and just use a marker line at 0.

Thanks William, I'll try your solution and keep you in tonch !

Hello Will,

I tried your solution, however, my axis still appears to the minimum of the Y Axis value (cf screenshot) even if I have set the marker to 0.

Any other ideas

?

Thanks
Steph

NB : I think this is bug of the maker when the value (0 in our case) is not in the range of the Y-Axis.
Further more, I can't set the orgin of the X-Axis to 0 because it won't manage anymore the case where there are both positive and negative values.

I thought it might also be possible by scripting and set the X-Axis start to Y=0, however, I am not an expert of this.

Help will be much appreciated

Thanks
Steph

Sorry for my poor description. With only positive values, you could set the axis minimum to 0. If you have positive and negative values, I meant that you could set a marker line at 0 to look like the origin line. You could use script and set the minimum value to 0 if all values in the chart are positive. Then, you could leave the marker line set for the case in which you have negative values. Let me know if you need help setting the minimum to 0 in script in the case of all positives.

I figure a way by scripting to force the X axis to start at Y=0 according to specific rules.
On the fetch of my dataset, I create a boolean global variable to tell if there is only positive or negative values.
Then in my chart, I put another script to set my origin of Y to 0 if there is only positive or negative values.
(and then if you hide the X-Axis and display a marker line to Y=0, you should always see a X-line starting at Y=0)

Thanks for the idea mwilliams !

I put a rptdesign in attachment, hope it my help some people

You're welcome! Always glad to help!

Thanks for the update on the situation! You might also make a devShare entry for this for more visibility!

<blockquote class='ipsBlockquote' data-author="'mwilliams'" data-cid="85294" data-time="1321307392" data-date="14 November 2011 - 02:49 PM">
You're welcome! Always glad to help!

Thanks for the update on the situation! You might also make a devShare entry for this for more visibility! </blockquote>
Hi Williams, 
 
I am using Birt 3.7 to create bar chart with 3 series, i have tried the script which you have provided to set minimum value to 0, i am facing a problem where incase if value has both negative and positive, y-axis for negative value is not happening. could you please provide me the solution.

Can you attach a sample that shows your issue?

'mwilliams' wrote on '27:

 
Can you attach a sample that shows your issue? 
[/quote 
The 0 line missing as a result the bars seem to hang in the middle of the chart. Please find the attached sample.

Hi Williams,

Thanks for your reply, if I force to set the y-axis minimum to 0 through script, I am facing an issues that incase value has both positive and negative in y-series, then y-axis scaling is not happening for negative value.
If y-series has only positive or negative value, then line is set to 0. this case its working fine. so could you please provide a solution for this issue.

please find the attached sample for this issue

Sorry, I meant a report design example, that I can run, so I can do some testing. You can set this up with the sample database or any other type of dataSet that you can provide me, i.e. scripted, flat file, etc.

<blockquote class='ipsBlockquote' data-author="'mwilliams'" data-cid="111966" data-time="1354321831" data-date="30 November 2012 - 05:30 PM">
Sorry, I meant a report design example, that I can run, so I can do some testing. You can set this up with the sample database or any other type of dataSet that you can provide me, i.e. scripted, flat file, etc. </blockquote>
Hi, I have designed the file using scripted dataset, If I tried to set the marker line only for positive values using the script, then problem here is incase the value as both positive and negative then negative scaling is not happening. Please have a look at the attached files.

Take a look at this modified report. I check the chart for negative values in the afterDataSetFilled and change the value of a variable to true, if there are negatives. Then, I wrapped your setting of the axis to 0 in a check for this value so that 0 is not set for the y-axis min, if negatives exist. Hope this helps.

Thanks Williams, I have tried with the solution which you have provided, its working as expected for 3-series bar chart.

Requirement is I need to hide the series2 based on the parameter, so it has only 2-series in that case again the y-axis starts from minimum value, so it would be helpful if you can provide me the solution.

Thanks,
Jain

I don't see a parameter on your report. So, you're wanting to add a parameter that chooses a series to hide? Then, decide based on which are visible whether you need to start at 0 or not? Let me know.

<blockquote class='ipsBlockquote' data-author="'mwilliams'" data-cid="112084" data-time="1354733809" data-date="05 December 2012 - 11:56 AM">
I don't see a parameter on your report. So, you're wanting to add a parameter that chooses a series to hide? Then, decide based on which are visible whether you need to start at 0 or not? Let me know. </blockquote>
Hi mWilliams, Thanks for your reply. X-axis to start at 0, Requirement is to hide the series2 based on the parameter (if param is null) if I tried to hide series2; incase series2 as some negative value and other two series series1 and series3 as all positive values then x-axis starts at minimum value, so this should not happen. X-axis should always starts at 0, I have attached the snapshot and report design file for your reference. I dont find any solution could you please help me out on this.

Take a look at this one.

Thanks William, I have tried with your solution and its working as expected.

Great! Let us know whenever you have questions!

Hi, If all the values are negative, then positive scaling should not happen. In some cases its happening. Is there away to control that? could anyone please share your ideas.