FOR EACH object in object

I am trying to find a MATLAB equivalent to FOR EACH object IN object such as in vba/c++.

Private Sub cel_OnQueryProgress(ByVal query As (CQG.ICQGOrdersQuery, ByVal Error As CQG.ICQGError)

Dim Query as CQGOrdersQuery
Dim Order As CQGOrder

For Each order In Query

Next

Answer 1

[Todd Flanagan]

for in MATLAB behaves a lot like FOR EACH.

If you say:

for idx = 1:10

you are saying

FOR EACH idx IN [1 2 3 4 5 6 7 8 9 10]

So you can do stuff like:

>> group = ['a' 'b' 'c'];
>> for member = group
     disp(['the member is ' member])
   end
the member is a
the member is b
the member is c
>>

[Julian]

I may of misunderstood your answer, if so please correct. But where i say 'Object' i mean class object which is not a structured array structure.

So size(ObjectK) = [1 1] but contains child objects say ObjectJ J=1...N

So i am after:

For EACH ObjectJ IN ObjectK

where N (no of child objects is unknown)

Many thanks

[Walter Roberson]

I am not sure what you mean by saying that the object "contains" child objects? Do you mean you have a class and wish to find all living objects that are members of the class, even ones in different workspaces ?

[Todd Flanagan]

I think what you are seeing is a bit of convenience from VB. CQGOrdersQuery has a property named Orders that returns a collection of CQGOrder. When you use FOR EACH on the Query Object, I'm guessing that it is getting the Collection from the Orders property by convention. MATLAB isn't quite set up that way.

[Geoff Olynyk]

I'm running into this same problem trying to use the Solid Edge COM API from Matlab (this is a drafting program). There are many objects, say, 2D lines in my drawing, which I'm trying to get the properties of from Matlab. In VB.NET, you would call it something like:

For Each line2d As SolidEdgeFrameworkSupport.Line2d In dftDoc.ActiveSheet.Lines2d

Console.WriteLine(line2d.Name)

Next

What's the equivalent in MATLAB? How do I get the Name (or any other field) of every Lines2D object in the document?

Answer 2

[Geoff Olynyk]

Julian,

This has stumped me for the past week, but I think I have it cracked. (At least, this makes sense for my application, which is controlling Siemens Solid Edge ST2 via the COM API. Hopefully you can confirm for your application?)

Visual Basic has the shorthand For Each Object In CollectionClass, which takes advantage of a special field (attribute) Count and a method Item() belonging to "collection class" objects, which are designed to collect other objects (cells in a spreadsheet, 2D lines in a CAD drawing, etc.) See the MSDN reference below.

The field Count just returns the number of Objects in the CollectionClass (an integer), and the method Item(i) returns the i'th Object in the CollectionClass. (In your case, the i'th Order in the Query collection class.)

So to replicate in MATLAB, you would do:

objQuery = CQG.ICQGOrdersQuery ; %  define collection class object
nOrders = objQuery.Count ; % number of orders in Query collection class

for k = 1:nOrders, ; % loop through objects in collection class
  objOrder = objQuery.Item(k) ; % get handle for Order object
  objOrder.DoStuff() ;
end

Like I said, this works for my problem, trying to loop through things like reference planes, lines, circles, etc. via the COM API for Solid Edge. Let me know if this makes sense for you!

References:

http://msdn.microsoft.com/en-us/library/cy13e6ex%28v=vs.80%29.aspx

http://msdn.microsoft.com/en-us/library/61h34247%28v=vs.80%29.aspx

http://stackoverflow.com/questions/10000289/how-do-i-loop-through-every-object-in-a-class-like-vb-for-each-x-in-y-in-matla (this is me asking the same question as you do here, on Stack Overflow)

Answer 3

[Walter Roberson]

I am not familiar with VBA, so I might well be missing something, but in MATLAB you can do

for order = Query
  ...
end