Making API for energy calculation, unable to "Set Parameters for certain walls to certain directions"

[allazaruszcheong_21]

Developing RevitAPI, calculating net energy transfer by a bulidng, it involves the directions of the walls, it works on a simple model, but not a more complicated real life model. Need help.

//Checking for SouthWest Facing Walls & Windows
bool isSouthWestFacing = IsSouthWestFacing(exteriorDirection);
if (isSouthWestFacing)
{
SouthWest_Wall_Lst.Add(WE);

inserts_0 = (WE as HostObject).FindInserts(true, true, true, true);

ParaSouthWestWall = WE.LookupParameter("SouthWest");
using (Transaction trans = new Transaction(doc, "ETTV_1"))
{
trans.Start();
ParaSouthWestWall.Set(1);

foreach (ElementId emtid in inserts_0)
{
Element emt = doc.GetElement(emtid);
emt.LookupParameter("SouthWest").Set(1);
}
trans.Commit();
}

}

the first error occurs when i try to set(1) the SpecialParameters "southwest" to a checkbox 

[allazaruszcheong_21]

error message

[ctm_mka]

I assume the parameter "SouthWest" is a custom parameter you assigned to the wall category? Is it a type or instance parameter? Your setting of a boolean value is correct, its how you are retrieving the parameter that is suspect. I believe error message means the parameter does not exist where you are looking for it.

[allazaruszcheong_21]

yes it is a custom parameter applied,  the thing is, the program works on a simple model but not a complicated real life building, so i believe the code works, but maybe there's a discrepancy in the more complicated version of the model? Either way i have not found a way to trouble shoot it. 

[RPTHOMAS108]

This is odd behaviour but it likely relates to using LookupParameter which isn't ideal. I note that you have used a parameter with same name on the host object and on the inserts of that host object.

If your parameter is shared then reference it using its GUID, if it isn't then perhaps consider making it shared to do so. There may be something else going on but the code looks simple enough.

[allazaruszcheong_21]

Yes, "parameter with same name on the host object and on the inserts of that host object" on code and on Revit, they share the same parameter name. if that is what you mean, yes the parameter is shared if i am correct, i have a txt file named shared_parameters.txt, i will try using the GUID, but i have trouble accessing it and do not know how to.

[ctm_mka]

Did some further testing. I'm guessing when you say "Simple model" it was not an actual wall object? I say this because walls are system families, and their parameters may need to be accessed differently. So here's a code example to access both instance and type parameters (shared or not is irrelevant) of a Wall object. Note the element needs to be dim'd as a Wall object first to get at the type parameter. 

Wall walltest = element as Wall;
string typevalue = walltest.WallType.LookupParameter("Name of Type Parameter").AsValueString();
string instancevalue = element.LookupParameter("Name of Instance Parameter").AsValueString();
               

[allazaruszcheong_21]

In the real model, the walls are a "WallType", in the simple model, the walls are also a "WallType"

[allazaruszcheong_21]

This is my current error

[ctm_mka]

so then, what is the code defining "room"?

[allazaruszcheong_21]

Hi, 

Sorry for the late replay, 

It filters by OST_Rooms, is that fine?

[ctm_mka]

so you are looking for a parameter from a room element and not a wall element? im confused.

[allazaruszcheong_21]

Sorry i should have been clearer,
The past groups working on this project assigned "Air-Conditioned" parameters to the rooms.

For the calculation to take place, it only involves the external walls of a building, no internal walls considered, as well as the rooms of those walls must be AC-Spaced in order to be used in the calculation.

So basically, -> find rooms that are AC-Spaced, then find the walls that are external, then get those walls' orientation. Any windows involved are also considered

[ctm_mka]

Okay then, First, are you still having issue with reading the wall parameter? Second for the room, the solution is probably very similar, with a room being a system family.

[allazaruszcheong_21]

The issue with the walls suddenly went away, not sure what i did as i did not change the program nor revit model.
Also i noticed something, 

The first picture is a real life model,
The second picture is a sample model provided by my teacher.

I'm not sure but i feel like the room should be highlighted in the first picture? Maybe thats why its unable to detect it?

[ctm_mka]

Thats really weird the wall issue just went away.  I'm not familiar with Rooms (we don't use them, not an architect) to know about the selection thing. For the parameter itself, I can only reiterate what I've said, depending on if its an instance or type parameter, affects how you access them with the LookupParameter method.

[allazaruszcheong_21]

I apologize its my first time learning RevitAPI and i am a complete newbie, my teacher just threw me this project along with 0 knowledge on C# and RevitAPI, i am completely struggling, will get back to you ASAP after i figure out what you mean

[ctm_mka]

Ahhh okay, Then I definitely threw a bit much at you. The quick and dirty version of instance vs type parameters.  when you select an element, if you can see the parameter in the properties palette, it's an instance, and can usually be accessed with Element.LookupParameter. If you have to edit the elements type, it's a type parameter, and can usually be accessed with Element.Symbol.LookuParameter. Unless, of course, in your case where we are dealing with System families. Thats where the extra step of looking at the "WallType" (for walls) comes in.

[allazaruszcheong_21]

This stuff is such a headache...

[allazaruszcheong_21]

Okay, so i think i have to try to find out what type of variable i am trying to access and edit to make it a " " right? Its either an instance one or a Type parameter, i don't see the variable on the properties palette/tab so i think its a type parameter...