I want to represent in Protégé a container of balls. I have a RedBallContainer class that is a Container and a RedBall that is a Ball, like in this figure:
I have created a property Contains that has domain Container and Range Ball.
Now I wanted to say "a container is a RedBallContainer if only contains red balls". To do this I added the following rule:
Now, when I run the reasoner, it says me that the Container class is equals to Thing, but I think it is wrong for what I wanted to represent! Here there is a picture of what the reasoner infers:
What am I doing wrong?
Well, your restriction rule is incorrect. It says
"RedballContainer is equivalent to a class that only contains RedBallContainers"
It should be:
"RedballContainer is equivalent to a class that only contains RedBalls"
Edit as you found out the above fix does not remove the strange inferred equivalence relation. The reason it's there is somewhat convoluted, but it's roughly this:
we know that the domain of contains is Container, so anything that uses a contains property is, by definition, a Container.
we know that RedBallContainer is equivalent to anything that contains only RedBalls, so any item that contains only red balls is a red ball container.
we also know that RedBallContainer is a subclass of Container.
Now imagine some item that is not a Container. Two options are possible: it either contains something, or nothing. If it does contain something, by definition 1 it still is a Container after all.
However, if it does not contain anything, that means that all the balls it contains are in fact red balls (because none of the zero balls it contains are not red balls)! By our second definition, this thing therefore is a RedBallContainer. By our third definition, it therefore must be a Container after all.
In short, under this set of rules it's not possible for something to not be a Container. Everything is a Container, so Container and Thing are equivalent.
Ah, logic.
To fix, you could change your restriction to say that a RedBallContainer is equivalent to any Container that only contains red balls:
EquivalentTo Container and contains only RedBall
Related
I'm performing some geographical computations in a grid with squares (i.e. regions). I'm using Delphi, but the logic could probably be applied to C++ too. Let me first explain what I want to do.
The following image is a portion of my grid, which is represented by a two-dimensional array Square that denotes the centre point in each square, and the "movement through the layers":
The green square has an X and Y coordinate of 2, so that is Square[2,2]. The actual coordinates are stored in Square[2,2].Latitude and Square[2,2].Longitude as wel as extra information in e.g. Square[2,2].Info that I use for computations.
Now comes the purpose: I need to do some computations on the surrounding areas. How many of the surrounding areas can be called "neighbours", depends on how many "layers" I have defined. In the image above, I used two of these "layers". That means that when starting from the green cell, I go around it once (blue arrows) and then again in the second layer (red arrows).
Now comes the problem: if I would have started in Square[1,1] (green square) instead of Square[2,2] as in the image below, the second layer (in red) would try to access data on the left side and at the bottom that does not exist (i.e. in the "-1" column and row). See the image below. This problem occurs at all borders of course.
I probably can make exceptions with IF-statements for every scenario, but I was wondering if there are common programming "tricks" that can handle such situations where you try to access data does not exist.
For example, I imagine it would be very handy if I can follow the pattern of the arrows depicted in the first image to access all the neighbouring squares every single time, even if there are non-existing squares. So, looking at the first image, after Square[3,0] you'd go to something like Square[3,-1] etc. and then eventually come back into the "feasible" zone in Square[0,3].
To visit neighborhood, you can use some kind of BFS (breadth-first search).
But for sparse structure (like the last picture shows) it is worth to use some data structure to organize cells in a good way. Perhaps kd-tree is suitable - you add all existing cells in the tree and make range search around given cell to get other cells in its vicinity.
Also look at another spatial data structures (see list at the bottom of kd-tree page).
Is there a way to know is certain FrameworkElement was rendered to the screen. For example. I have two rectangles, and one overlap other. But I'm not sure about "how much" one overlap other.
So I need to know is user will see both rectangles, or will see only one, or will see one fully and one partially?
It all depends on what kind of parent container it is, if both rectangles are inside StackPanel then they will not, you have to either make a custom container or use canvas as parent of these rectangles.
Then you can get LocalToScreen or such similar methods to get their absolute positions compared to screen or top parent window and find out whether they overlap or not.
I have a report which displays customer address in multiple labels.
My customers use windowed envelopes for mailing. I need the address labels position to be configurable.
Something like, I'll have a database table which stores the Top/Left position of each label per customer. Based on this table, I need to position the address labels on my report.
I thought, it is doable by expressions, but Location property doesn't provides ability to set an expression and make the label's top and left dynamic.
Anybody, any ideas, on how to achieve this?
As you mentioned, you cannot set an expression for location property. I want to do this before but it seems that there is no solution for this work.
Sorry for the duplicate post
I had the same problem as you did. I got around the problem by using an old HTML trick. It involves using a transparent.gif in an image. You put your image (linked to the gif), then put your label on top. Using a parameter, you can toggle which item to appear by setting an expression in the hidden property for both controls.
As stated by others, it isn't supported. However, here are two ugly work around possible for basic reporting.
Work around with padding.
You can't set formula on the label's location, but you can use padding option instead.
So you can set the label as wide as the report and as tall as the region.
Also, set the label's horizontal alignment to "Left" and Vertical alignment to "Top".
Then, add a formula in left and top paddings to offset the text.
You can also achieve a right aligned offsetted label by setting the Horizontal alignment to "right" and using right padding instead of the left one to offset the field from the right. With the same recipe, you can offset from the bottom by using "bottom" vertical alignment and bottom padding.
The ugly side:
This method will create a mess in the report designer as all dynamic label will overlap each other and take all the space over static label. Also, please note that with this method, you won't be able to do fancy stuff like adding borders around the text and hyperlinks.
Work around with sub report.
If the number of different positions for the label(s) are really low. You can create a subreport for each possibility and use a formula to display the right subreport for the right case. Sadly, this doesn't work for labels in the header as subreport aren't allowed there.
No solution, as it is not supported!!!
From MS online community support...
"As far as I know, the position of the textbox in the report is static not dynamic, so it will not shift to left."
Reference: http://forums.asp.net/t/1433297.aspx
I have a set of shapes which need to be drawn on top of each other. I need to re-order them such that the smallest shape gets drawn last (i.e. it will be closest to the user). Is there any way to check whether a shape overlappes (encloses and/or intersects) another shape. I know there is a method in Rect structure called Contains which checks whether there is an object within it. Is there a similar method or a way to simulate it on Shapes in WPF? Thanks in advance for any help.
Cheers,
Nilu
You could probably use the Geometry.FillContainsWithDetail method. Its name is ill-chosen IMHO, but the description is clear :
Returns a value that describes the intersection between the current geometry and the specified geometry.
I have successfully used it for collision testing before, so it should work for you too...
WPF has the Typography.Variants attached property that lets you do superscript and subscript. However, it only works for some fonts. For other fonts, the variant is utterly ignored, and the text is shown normally. (Code sample and screenshot here)
Since it silently falls back to a no-op, I have no idea that anything went wrong; but my user will see lousy behavior.
Is there any way that I can programmatically detect whether a given font supports Typography.Variants? If so, I could provide more meaningful behavior if the user selected a non-variant-supporting font for something that needs superscripts/subscripts.
I looked at GlyphTypeface, since it's the one you use to query whether a font can be embedded, but I didn't see anything there about variants. I also didn't see anything obvious on FontFamily, and the only thing I could find on Typography was the Variants attached property itself (and its getters and setters).
As far as I can tell, WPF provides no information about the available GSUB tables (which tell you this information). Everything is hidden deep within private classes of PresentationCore.
One way would be to use the advanced text services of WPF to create a TextFormatter, and then retrieve the GlyphRuns created by a piece of text with the variants on, and one with the variants off, and then compare the glyph indexes used.
Another way would be to physically examine a font's data through GlyphTypeFace.GetFontStream(). The TrueType font format is not very complicated, so you'll probably find some information on the net on how to parse the binary font data to find information on the GSUB tables.
Note that simply asking wither a variant is supported is also a little ambiguous. A font can say it supports a variant, but nothing requires it to actually provide any meaningful substitutions. Most Adobe fonts provide only a few alphabetical lowercase characters for things like superscript and subscript (not even the entire Latin alphabet, mind you). Which is pretty useless, IMHO, since you can't ask WPF to fake subscripts or superscripts like Word and other word processors do.
Still, it would have been nice if you could simply ask TypeFace.GetSupportedOpenTypeFeatures().