OBM math expressions in Template variables do not work!

Are there any Bentley experts to reply this question?  thanks

Hi Chen,

This option is working as designed, without problems in the release market version that you have installed.

When you add a formula you need to choose and existing variable to connect your desire values.

As you will see in my video, I have added a formula for my ,,right lane'', to be always multiple of 5 face of my ,,left lane'' value.

First you need to place your deck ( after in a previous step you added your math expressions ), and after you need to open the ,,variable constraints'' and you need to activate that variable that is inside of your math expression. After you will make active that variable and you will hit ,,ok'', the program will read the expression, will read the value of your ,,variable'', and he will apply this expression.

Notice that I've added a math expression that my right lane, need to be always equal with: left lane * (-5 ), and everything was okay.

Take note to include in your math expression also and the sign conventions accordantly.

The left lane is negative always and the right lane is positive always. That's why I added formula in this way [ left lane* (-5 ) ]

(-)from the left lane * (-5) = positive value will result , and this is the expected convention for the right lane in this case. 

Like a summary:

The changes of your math expression will be done just when your deck will be already placed, when the math is already added for that deck, and when the variable that is connected to your math expression will be active.

Please look at the video and if something is not clear, please leave a message and I will come back with more details.

Hi Andrei,

Thanks for your detailed instruction, I have got it by your video, and have completed the math expressions input as what you did.
I find that the “math expressions in Template variables” function can not be showed until the deck is placed, and the variable constraint is added.
So the “math expressions in Template variables” can not be showed and can not be tested in the Template Creation dialog and the template verify dialog, which make me confused, please see the following screenshot.

The horizontal distance of p_1 = LT_Width_Lane1*(-2), Value = 6.1
The horizontal distance of p_5 = LT_Width_Lane1 , Value = -2
But, Changing the value of horizontal distance of p_5 can not change the value of horizontal distance of p_1, Even in the template verify dialog, I think this is not enough rigorous.
For this example, if horizontal distance of p_1 = LT_Width_Lane1*(-2), then the Value should be equal to 4.0, and can not be edited.

Thanks and regards

Regards,

Hi Andrei,

Thanks for your detailed instruction, I have got it by your video, and have completed the math expressions input as what you did.
I find that the “math expressions in Template variables” function can not be showed until the deck is placed, and the variable constraint is added.
So the “math expressions in Template variables” can not be showed and can not be tested in the Template Creation dialog and the template verify dialog, which make me confused, please see the following screenshot.

The horizontal distance of p_1 = LT_Width_Lane1*(-2), Value = 6.1
The horizontal distance of p_5 = LT_Width_Lane1 , Value = -2
But, Changing the value of horizontal distance of p_5 can not change the value of horizontal distance of p_1, Even in the template verify dialog, I think this is not enough rigorous.
For this example, if horizontal distance of p_1 = LT_Width_Lane1*(-2), then the Value should be equal to 4.0, and can not be edited.

Thanks and regards

Regards,

Hi Chen,

Unfortunately in this moment this math expression is working without the possibility to do checks and verifies in the template viewer.

We have tickets to enhance this thing and is on ,,our list'' to do, but I can't say exactly when we will resolve these small issues.

Also even if you will put a math expression, the value from the top will not be updated as it should be.

You need to test your math expression if they works as expected, in your model. This is the only solution in this moment.

After you will add a formula for let's say ,,right lane'', you need to place that deck, to activate the variable that is connected to your ,,right lane'', and just in this way you will be able to test the math expression.

The common situation where will not work, is the situation where the sign convention is wrong ( in this case if the program will expect ,,plus'' let's say, and in your math expression you forgot to multiply the variable that is with ( minus ),  with the sign  (-)  will not work.

Just make sure to have the sign convention corresponding , and will work for sure 

Hi Andrei, Thanks for your prompt reply, hope to enhance OBM to have the ability to check and verify in the template viewer as soon as possible, this function can make OBM more rigorous.

Hi Chen,

Welcome!

Sure, is on our list ,,to do'''

Great this workes for me