Quotes of the week [LWN.net]

Quotes of the week

Posted Jan 12, 2012 14:23 UTC (Thu) by zuki (subscriber, #41808) [Link]

This chart, despite being pretty, shows how 3D graphs are useless. It delivers nothing more than a 2D chart would, and pretty effectively obscures two important facts:

the slope: because of the third dimension, the line is wider and it's much harder to estimate the slope (one needs to look carefully to find the right "corners" of the ribbon to compare
the surprising increases that the the original e-mail talks about (when an unused function is removed, the functions it used become unused, leading to temporary spikes). With a simple line non-monotonicity would be self-evident.

Quotes of the week

Posted Jan 15, 2012 10:32 UTC (Sun) by MortenSickel (subscriber, #3238) [Link]

Agree absolutely! One of the goals of education should be to put 3d graphs on the "non used methods list".

Quotes of the week

Posted Jan 16, 2012 7:52 UTC (Mon) by steffen780 (guest, #68142) [Link]

You seem to be missing the point of these graphs. I don't think this graph was meant to convey hard data. The point is to illustrate three things:
- There's loads of unused methods.
- There used to be far more.
- There's a significant trend of reducing the count.

The graph does this. It being "pretty" adds to the visual appeal. Does it matter to you if there were 2800 or 2950 unused ones at some point? Really? Then don't use an imprecise graph, use the hard, cold data ;)

Quotes of the week

Posted Jan 16, 2012 11:36 UTC (Mon) by MortenSickel (subscriber, #3238) [Link]

To me, a 3D graph looks stupid and ugly. And if I want to try to read a value out of it, it is much more difficult. 3d graphs belongs imho together with <blink> tags in the digital garbage dump.

Quotes of the week

Posted Jan 16, 2012 14:45 UTC (Mon) by xav (guest, #18536) [Link]

On the contrary, and for all the reasons you underline, 3D graphs are damn useful: there's no better tool to hide unwanted data in plain sight (that percentage is too small => let me add some depth to the pie chart and voilà !)

Quotes of the week

Posted Jan 16, 2012 21:24 UTC (Mon) by mathstuf (subscriber, #69389) [Link]

3D pie charts are among the worst[1] since when you skew it so that you can *see* the depth, the areas and angles are no longer proportional.

[1]The worst are those trying to be thematic and graphing things with circles for each thing and using the data point as the radius instead of the area for each circle.

Have you actually read the mail itself?

Posted Jan 12, 2012 17:12 UTC (Thu) by khim (subscriber, #9252) [Link]

This particular cite explains a lot:

One of the side benefits of the unsung heros working at the conversion of our old-style macro driven generics to modern STL is that this looses us several unused methods per class converted.

Apparently tools looks for compiled code but when there are macroses involved it's not easy to remove some functions.

P.S. Interesting question: are they removing unused functions from released binaries or not? Adding "-ffunction-sections -fdata-sections -Wl,--gc-sections" to command line can shrink binary a lot in complex project...

Re: Have you actually read the mail itself?

Posted Jan 12, 2012 17:51 UTC (Thu) by mina86 (subscriber, #68442) [Link]

I even looked at http://cgit.freedesktop.org/libreoffice/core/tree/unusedc... and it looks to me like a straight forward list of methods that can be simply deleted without looking back.

Use of macros that generate methods would explain it a bit, yes.

Re: Have you actually read the mail itself?

Posted Jan 13, 2012 18:17 UTC (Fri) by spaetz (subscriber, #32870) [Link]

Rather than doing all that work themselves, they keep it for newbees to familiarize them with the code. It´s called Easy Hacks, and it works surprisingly well.