Confusion over query (list).

jrs_spedley · September 2017

I only want to do a simple featurescript but I'm getting stuck with Queries.

I find Extrude is annoyingly selective on which edges it will extrude into surfaces. To get around it I want to loop through a 'query' of edges and extrude and thicken them individually, then form a union into a single part. e.g. like a sketch of a spider's web.
The problems is when I try to loop through the query using "for (var edge in edges)" it often fails because 'edge' isn't an EDGE.

I've tried to use qEntityFilter but then I just get the whole previous query wrapped in another qEntityFilter query.

Am I missing something here, is a query just an array of key:value pairs where 'value' can be another list of key:value pairs?

Here is the basic output ...

for (var edge in definition.edges)
	println(edge);

outputs ...
{ key : queryType , value : UNION }
{ key : subqueries , value : [ { entityType : EDGE , historyType : CREATION , operationId : [ F3jrPebnT9OxNT9_0.wireOp ] , queryType : SKETCH_ENTITY , sketchEntityId : 2fa71c56-ffcc-4f50-be0c-e0d57dd11eba } , { entityType : EDGE , historyType : CREATION , operationId : [ F3jrPebnT9OxNT9_0.wireOp ] , queryType : SKETCH_ENTITY , sketchEntityId : 8f7c92d3-5654-4301-92fe-92ca18b45d8c } ] }

but what I [think I] want is  ...
{ entityType : EDGE , historyType : CREATION , operationId : [ F3jrPebnT9OxNT9_0.wireOp ] , queryType : SKETCH_ENTITY , sketchEntityId : 2fa71c56-ffcc-4f50-be0c-e0d57dd11eba }
{ entityType : EDGE , historyType : CREATION , operationId : [ F3jrPebnT9OxNT9_0.wireOp ] , queryType : SKETCH_ENTITY , sketchEntityId : 8f7c92d3-5654-4301-92fe-92ca18b45d8c }

I'm actually going slightly insane now !!!!

jakeramsley · September 2017

Here is our documentation of queries, which can explain it more in-depth and technical than I can:

https://cad.onshape.com/FsDoc/library.html#module-query.fs

FeatureScript Documentation:

Functions for constructing queries. Features that take queries as inputs should re-export this module.
Queries are used to refer to topological entities (vertices, edges, faces, and bodies) that FeatureScript operation and evaluation functions work on. A query is a map that contains instructions for how to find entities. For example, a query for all edges in a context looks like qEverything(EntityType.EDGE). Many queries can take subqueries as arguments, allowing for more complex nested queries.
Queries in general do not contain a list of entities in any form. Rather, they contain criteria that specify a subset of the topological entities in a context. To get an array of the entities (if any) which match a query in a context, use <b>evaluateQuery</b>. There is no need to evaluate a query before passing it into a function, including any of the Standard Library's operation and evaluation functions.
There are two general types of queries: state-based and historical. State-based queries select entities based on the model state, e.g. "All edges adjacent to a cylindrical face which touches this point." Historical queries select entities based on the model history, e.g. "the edge that was generated by feature extrude_1_id from sketch vertex vertex_id from sketch sketch_id." State-based queries cannot refer to entities that have been deleted. Most automatically-generated queries are historical, while queries more commonly used in manually written code are state-based.

I've bolded, which I believe is problem in what you are trying to filter as I only have a snippet of your code and summary of what you are trying to do.

If you explain a bit more in detail, we may be able to help more with an approach to writing your FeatureScript

jrs_spedley · September 2017

Exactly what I was looking for, thanks. Totally forgot about evaluateQuery but it is only my second featurescript!

Thanks.

P.S. it also clears up what a query is, it isn't the result you want but the way to get the result you want. Much like database access. I suppose you can create complex queries and then internally onshape can simplify them or buffer calculations to produce more efficient results.

Confusion over query (list).

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