First of all - thanks a lot for this package, graphviz is an awesome tool and having this interface library is really convenient. There a three point where I could use some help: 1. when I try to create a label with e.g.: textLabelValue "Hallo" - the compiler complains he can't match string with data.text.lazy.internal -- I have idea how to create lazy internal text ! 2. I know how to rotate the whole diagram (with landscape or rotate 90), but not how to keep all the text in unrotated position -- is there a command to do this ? 3. When I create a symmetric tree with two directions on the two sides. The tree gets completely messed up when I enter the right directions. (left graph ok but wrong edge dirs, right graph with correct dirs but gemetry scambled). - It has todo with ranking order which is based on the direction of the edges. I can fake it with reversing the arrows in the diagram, but my original graph data is coming directed ... Cheers Phil http://haskell.1045720.n5.nabble.com/file/n4888818/GraphA.jpg http://haskell.1045720.n5.nabble.com/file/n4888818/GraphC.jpg -- View this message in context: http://haskell.1045720.n5.nabble.com/Three-questions-to-graphviz-tp4888818p4... Sent from the Haskell - Haskell-Cafe mailing list archive at Nabble.com.
On Mon, Oct 10, 2011 at 9:44 AM, kaffeepause73
First of all - thanks a lot for this package, graphviz is an awesome tool and having this interface library is really convenient. There a three point where I could use some help:
1. when I try to create a label with e.g.: textLabelValue "Hallo" - the compiler complains he can't match string with data.text.lazy.internal
-- I have idea how to create lazy internal text !
import qualified Data.Text.Lazy as L textLabelValue $ L.pack "Hallo" That's the only question I know how to answer. Regards, Dave
Hi Dave, Thanks for the quick reply - it works now. - I wasted quite a bit time on this. I guess the "internal" bit in the compiler message confused me. Cheers Phil -- View this message in context: http://haskell.1045720.n5.nabble.com/Three-questions-to-graphviz-tp4888818p4... Sent from the Haskell - Haskell-Cafe mailing list archive at Nabble.com.
kaffeepause73
Thanks for the quick reply - it works now. - I wasted quite a bit time on this.
Alternatively, you can turn on overloaded strings, which allows constructing text values (along with other types that are instances of IsString) from string constants. Add {-# Language OverloadedStrings #-} at the top of your source file to enable it.
I guess the "internal" bit in the compiler message confused me.
It is a common idiom to put "internals" -- e.g. data type definitions -- in a module called "Internal". -k -- If I haven't seen further, it is by standing in the footprints of giants
On 11 October 2011 03:44, kaffeepause73
First of all - thanks a lot for this package, graphviz is an awesome tool and having this interface library is really convenient. There a three point where I could use some help:
2. I know how to rotate the whole diagram (with landscape or rotate 90), but not how to keep all the text in unrotated position -- is there a command to do this ?
I don't think this is possible: the rotation seems to be a post-processing feature done by GraphViz. If you just want the graph laid out Left-to-Right rather than Top-to-Bottom, try setting the RankDir attribute: http://hackage.haskell.org/packages/archive/graphviz/2999.12.0.3/doc/html/Da... (though I've just noticed that the Ordering attribute should take in a specific type rather than just Text... *goes off to fix*)
3. When I create a symmetric tree with two directions on the two sides. The tree gets completely messed up when I enter the right directions. (left graph ok but wrong edge dirs, right graph with correct dirs but gemetry scambled). - It has todo with ranking order which is based on the direction of the edges. I can fake it with reversing the arrows in the diagram, but my original graph data is coming directed ...
This means you need to tweak and play around with the settings more. My approach (and I'm the maintainer of the graphviz library!) for stuff like this is: * Get some sample Dot code (either write it by hand or use graphviz to generate it from your data). * Look through all the available attributes for ones that might deal with layout of nodes, edges, etc. at: http://www.graphviz.org/doc/info/attrs.html * Try setting them into your Dot code, then use the appropriate Graphviz command (dot, neato, circo, etc. depending on which layout you want); consider something like "dot -Txlib test.dot" to get a preview window up, or "dot -Tpng test.dot > test.png" to get a png image. * Once you've found attributes that seem to do what you want, use the graphviz versions of them in your Haskell code. Note also that because Graphviz uses automatic layout algorithms, you can't always get it to output in the way that would make sense if you drew it by hand. I've been told that things like phantom nodes (invisible nodes that you insert with extra edges to force spaces, alignment, etc.) can help, but I've never looked into using them enough to work out approaches of how/when to do so. -- Ivan Lazar Miljenovic Ivan.Miljenovic@gmail.com IvanMiljenovic.wordpress.com
Hi Ivan, I already played around a fair bit with options in both cases, but there are quite a few so it gets quite worky with try and error. Going to graphviz directly doesn't seem a bad idea. Thanks Phil -- View this message in context: http://haskell.1045720.n5.nabble.com/Three-questions-to-graphviz-tp4888818p4... Sent from the Haskell - Haskell-Cafe mailing list archive at Nabble.com.
On 11 October 2011 17:00, kaffeepause73
Hi Ivan,
I already played around a fair bit with options in both cases, but there are quite a few so it gets quite worky with try and error.
Definitely. I've never bothered fully documenting Data.GraphViz.Attributes.Complete fully solely because there are so many attributes, and at best I'd just be copy/pasting stuff from the upstream docs. As I add more "user-friendly" options to Data.GraphViz.Attributes, I'm starting to provide more specific comments regarding usage, etc. Basically: if I find a specific attribute to be useful with some corner cases or usage tricks where it's useful, I add documentation. I welcome anyone sending me patches (or even a chunk of text via email) about specific attributes to help flesh it out.
Going to graphviz directly doesn't seem a bad idea.
Well, it just takes the middle-man out of the loop. The upstream documentation is sometimes a little scarce about what all the attributes do, and playing around with them usually ends up being more informative. -- Ivan Lazar Miljenovic Ivan.Miljenovic@gmail.com IvanMiljenovic.wordpress.com
participants (4)
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David Barbour -
Ivan Lazar Miljenovic -
kaffeepause73 -
Ketil Malde