I want to use LineBuider to connect pairs of points. Thing is that they need to be grouped such that Attribute_A equals Attribute_B. All features contain both Attribute_A and Attribute_B. I am sure that there is a clever workaround for this, but I cant figure out how.
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Hi @aron ,
you can try out the following techique:
- get all the features where attribute A = attribute B with a Tester;
- group the feature by attribute A with an Aggregator and build a list with all the attributes;
- create an attribute _group_id with a Counter;
- deaggragate the features with a Deaggregator and explode the previous list;
- go to LineBuilder and group by attribute _group_id.
See the attached screenshot.
Hope that helps!
Hi @aron ,
you can try out the following techique:
- get all the features where attribute A = attribute B with a Tester;
- group the feature by attribute A with an Aggregator and build a list with all the attributes;
- create an attribute _group_id with a Counter;
- deaggragate the features with a Deaggregator and explode the previous list;
- go to LineBuilder and group by attribute _group_id.
See the attached screenshot.
Hope that helps!
Hi @aron ,
maybe there is an even simpler solution. Go straight from the Tester to the LineBuilder and group by attribute A.
Unfortunately I can't get this to work. I realise I was a bit vague in my initial question.
I have two different "data streams" with points. Lets call them Point1 and Point2. Each point has Attribute_A and Attribute_B.
I would like to find features from Point1 where Attribute_A or Attribute_B match Attribute_A or Attribute_B from Point2. And then connect the matching pairs with a line.
On the stream with point B change the attributename to Attribute_A and use this as GroupBy parameter. If you want the attribute back you can copy the Attribute_A parameter back to Attribute_B afterwards.
Unfortunately I can't get this to work. I realise I was a bit vague in my initial question.
I have two different "data streams" with points. Lets call them Point1 and Point2. Each point has Attribute_A and Attribute_B.
I would like to find features from Point1 where Attribute_A or Attribute_B match Attribute_A or Attribute_B from Point2. And then connect the matching pairs with a line.
Will there only ever be one match?
I think I'd be inclined to extract the Coordinates as Attributes from the dataset, then use an InlineQuerier to transfer coordinates from the Point2 dataset to the Point1 dataset where Attribute A = Attribute A or Attribute B = Attribute A or AttributeB = AttributeB or AttributeA = AttributeB, then vertex creators to create the line
SELECT P1.AttributeA, P1.AttributeB, P1._x, P1._y, P2._x, P2._y FROM Point1 P1, Point2 P2
WHERE P1.AttributeA = P2.AttributeA
OR P1.AttributeA = P2.AttributeB
OR P1.AttributeB = P2.AttributeB
OR P1.AttributeB = P2.AttributeA
Unfortunately I can't get this to work. I realise I was a bit vague in my initial question.
I have two different "data streams" with points. Lets call them Point1 and Point2. Each point has Attribute_A and Attribute_B.
I would like to find features from Point1 where Attribute_A or Attribute_B match Attribute_A or Attribute_B from Point2. And then connect the matching pairs with a line.
@aron ,
do you mean this?
point1.A = point2.A or
point1.A = point2.B or
point1.B = point2.A or
point1.B = point2.B
Unfortunately I can't get this to work. I realise I was a bit vague in my initial question.
I have two different "data streams" with points. Lets call them Point1 and Point2. Each point has Attribute_A and Attribute_B.
I would like to find features from Point1 where Attribute_A or Attribute_B match Attribute_A or Attribute_B from Point2. And then connect the matching pairs with a line.
Hi @aron ,
I think @ebygomm found a nice solution . I can't try out it right now, but it should work using two VertexCreator in sequence in mode 'Add Point'.
Bye.
This should do the trick.
Will there only ever be one match?
I think I'd be inclined to extract the Coordinates as Attributes from the dataset, then use an InlineQuerier to transfer coordinates from the Point2 dataset to the Point1 dataset where Attribute A = Attribute A or Attribute B = Attribute A or AttributeB = AttributeB or AttributeA = AttributeB, then vertex creators to create the line
SELECT P1.AttributeA, P1.AttributeB, P1._x, P1._y, P2._x, P2._y FROM Point1 P1, Point2 P2
WHERE P1.AttributeA = P2.AttributeA
OR P1.AttributeA = P2.AttributeB
OR P1.AttributeB = P2.AttributeB
OR P1.AttributeB = P2.AttributeA
Thanks @ebygomm !
I tried this but could not get it to work for me. First time with this transformer for me and next to no previous experience of SQL, so i'm in pretty deep water...
I got it to work so far that it does merge the attributes. But it also creates loads of duplicates. Any ideas on how to produce a "clean" output?
(I tried to clean up the data with a Matcher, but did not manage to get it to perform well)
Will there only ever be one match?
I think I'd be inclined to extract the Coordinates as Attributes from the dataset, then use an InlineQuerier to transfer coordinates from the Point2 dataset to the Point1 dataset where Attribute A = Attribute A or Attribute B = Attribute A or AttributeB = AttributeB or AttributeA = AttributeB, then vertex creators to create the line
SELECT P1.AttributeA, P1.AttributeB, P1._x, P1._y, P2._x, P2._y FROM Point1 P1, Point2 P2
WHERE P1.AttributeA = P2.AttributeA
OR P1.AttributeA = P2.AttributeB
OR P1.AttributeB = P2.AttributeB
OR P1.AttributeB = P2.AttributeA
If there is only one pair matching between each attribute I don't think there should be any duplicates with this method. If in fact the value of AttributeA in Point1 dataset exists in both AttributeA and AttributeB in the Point2 dataset then you need some logic to decide which one to match.
Thanks for all the help everyone! I learnt much. In the end I found a solution where the problem got solved earlier in the workspace, and in a much simpler way.
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