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mass property parameters


New member
I am trying toequate a parameter (real number) to the y coordinates of cg andget the following error

Y_Y=mp_cg_y ("", "CSO" ,"")
errorInvalid data type combination at right side of expression

Following is the help example

Using 2001. What am I missing?
a = b + mp_cg_x ("", "CS0", "").
Mass Property Parameter


New member
Hm I remember that when I use this help and copy paste it into my relations there were also error. Well problem was in "" , try to type them instead copy/paste.


New member
robertib: Thanks, but I am using 2001

Isair: Thanks, but I have tried typing it directly and it makes no difference.

I am still stuck



New member
There is the BMX (Behavorial Modeler) orAAX module you must have to use the CG parameters. This may be your problem. To find out: Insert> Datum > Analysis If you can do this, you have the Behavorial Modeler license.
Edited by: donha


New member
donha: Yes I do have BMX and can create a datum analysis feature

copyboy: Yes I do have CSO

Thanks, but still stuck!


New member

It will workfor sure but you need to enter the name correctly.

its CS0 (C, S and Zero) and not CSO (the name of the co-ordinate system should be exactly same)

Try this and give us your feed back.



New member
In my model i have a co-ordinate system with a name of "PRT_CSYS_DEF" and i tried the following formula .....it worked

Y_Y = mp_cg_y("", "PRT_CSYS_DEF","")

also remember there should not be any blank space between two inverted comma (it must look like this "" .......and not like " ")

i hope this will be clear for you

Prashant Patel.


New member
Jeff and Parshu: You hit the nail on the head. I was using CSO rather than CS0(zero). The obvious always seems to be the first thing I overlook.

Thanks for all of your help!