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units of trig function ie [ tan(theta) ] not unitless?

units of trig function ie [ tan(theta) ] not unitless?

units of trig function ie [ tan(theta) ] not unitless?

This is puzzling:

When using the expression editor to input a formula including a trigonometric function (like: tan(theta) ), the function will only yield an answer IF the units are set to something OTHER than "constant".  If the units are set to "constant", the formula returns "0" regardless of the inputs.

Now, I seem to recall that the tangent of an angle is UNITLESS - so why this strange behavior on the part of UG (NX3)?

By the way, this makes it hard to, say, evaluate the solution to another formula which depends on the correct assignment of units (length, area, constants, etc) in order to give an answer without crashing.

Any comments?  Is this a known issue?

RE: units of trig function ie [ tan(theta) ] not unitless?

I set test1=tan(30) and got the right number (0.577 something), but it depends what I set the dimension type to as to how it behaves.  If I set test1 to be a length, then test1 is 0.577mm.  If I set test1 to be blank or constant), then the number is dimensionless.  If I try to divide a Force with an area to get a pressure, however, odd things happen.  This is with NX3.0.0.21.
How does this differ with the behaviour you are seeing?

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