Anthrazit

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1 years, 208 days

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These are replies submitted by Anthrazit

Probably found a workaround.

  • generate a new, empty array
  • redefine variableName of the datatable to the new array
  • expand number of rows to the number of the old array
  • redefine variableName to the old array

Datatable.mw

@dharr 

Something in that code doesn't work, I get a "recursive assignment" error.

@Carl Love 

This is all incredibly useful, especially the use of angle-bracket operators. In my case, getting the result back as an array is actually better than as a list.

However it is not easy to find that information in Maple Help or somewhere else. So I guess this will not be my last question regarding expression sequences.

@nm 

This was very helpful, just needed to go through almost every single character you had in your reply...

This is interesting, wouldn't have had a chance to find out by myself just reading the help files though.

Btw., I've also tried with the evalb function, but that gave the same error.

Need to get back to my very first question in this forum once again.

Could someone please explain the meaning of this information in the help files?

If <Maple>\lib\maple.ini exists, it is loaded first (where <Maple> is your Maple installation directory). With a network installation of Maple, the commands in this initialization file will be executed by all users on the network.

What exactly is a network installation?

In our case - where on the network should we place a common maple.ini file?

Just did a test with 2 users working on the same workbook or worksheet, and we must confirm that there is absolute no mechanism in place to prevent a complete chaos. The last one to write a file is the boss and overwrites everything done by someone else.

I consider that a very serious bug.

Maple should prevent opening its files in write modus when someone else already has a file open.

I'll file a report on that one.

Here's another big problem to this issue.

If conditions exit with error if one of the variables in the comparison becomes zero (and loses its unit).

Units_disappear_error_in_program.mw

@Carl Love

Wow! 

@Thomas Richard 

Thanks a lot!

@Anthrazit 

I've got a reply from support, see attachment.

---

Thank you for contacting Maplesoft, and for your email.

We appreciate your feedback on this, and have heard similar reports from customers in the past.

This limitation of Maple is known and is documented in our help pages. Relating to temperature the following is stated in the page ?convert,temperature​:
 

Expressions with a unit are represented in Maple as a product of the expression with a function call, which can be obtained by calling the procedure "Unit". This means that Maple cannot represent the expression "0" with a unit: it would be represented as, for example, "0*degC", or internally, "0 . (Unit(degC))", but "0" multiplied by any function call immediately simplifies to "0". This particularly comes up with temperatures sometimes, when dealing with empirical temperatures rather than with temperature differences. This can be a reason to use Temperature objects instead of regular unit expressions.

 

I am sorry for any confusion this has caused. Let us know if you have any further questions or concerns.

Regards,
Brock,
Manager Customer Success

I just wanted to apologize for using "moment" for something that absolutely is no moment at all.

Moments would be in kN*m, while this is a simply a force / m.

As an engineer I am much more comfortable with the way Mathcad handles these things.

@dharr

I've filed a technical support request. Let's see what they come up with. 

@dharr 

I consider this to be a very bad behaviour, as you see in this example. Units must be retained, and must not disappear, even when the value is zero.


 

(15*(.5-.5)*Unit('kN'/'m')*5)*Unit('m')

0.

(1)

temp := 0*Unit('`&deg;C`')

0

(2)

temp

0

(3)

convert(temp, units, Unit(Unit('`&deg;F`')))

0

(4)

``


 

Download Units_disappear.mw

 

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