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picokuo
18th January 2011, 14:26
Hi, Sir:
I want to set label under the bar of histogram chart. But, I can't find a way to do.
Could you please give me some solution?

What I want is shown on the attached file.

d_stranz
19th January 2011, 02:02
Did you bother to read the answer to yesterday's post by Patrik, who asked EXACTLY the same question?

That's the purpose of this forum, to provide a place where you can search for answers to common questions before you ask the same thing again.

And anyway, you are not talking about a histogram, you are talking about a bar chart. These are two completely different concepts. See my answer to Patrik.

http://www.qtcentre.org/threads/37878-How-to-show-all-labels

Uwe
19th January 2011, 07:01
And anyway, you are not talking about a histogram, you are talking about a bar chart. These are two completely different concepts. See my answer to Patrik.
Even worse - the screenshot shows a special bar chart, where each bar is accumulated from values of several corresponding samples. I remember such a contribution for an earlier version of Qwt, where the author implemented a MultiBarItem, that was able to display the bars side by side or stacked.

For such a thing it makes no sense to try something with the existing plot items. Instead use Qwt 6 and implement your own.

Uwe

PS: Writing plot items for bar charts is on my TODO list - but not for Qwt 6.0 anymore

picokuo
19th January 2011, 07:09
Hi, d_stranz:
Thanks a lot.
I indeed don't find the reply from you to Patrick.
That's because I find similar questions based on my guess. (forget "label"...)

Sorry for that.

BR,
Pico

d_stranz
21st January 2011, 05:07
Even worse - the screenshot shows a special bar chart, where each bar is accumulated from values of several corresponding samples. For such a thing it makes no sense to try something with the existing plot items. Instead use Qwt 6 and implement your own.

PS: Writing plot items for bar charts is on my TODO list - but not for Qwt 6.0 anymore

I also wrote such a thing for Qwt 5.x; my bar chart items could be stacked, put side-by-side, or clustered into groups. This was before I understood the axis engine / scale / draw concepts, so the labels didn't work correctly. Now that I think I understand what to do, unless 6.0 is radically different I will port it over and do it right when I get around to porting to 6.0. I don't see any reason not to contribute the code if you're interested.

David