partial derivatives of more than 2 variables

[AlfredLeick]

Hi,

I cannot take the partial derivatives of a function with 4 variables.

Taking partial derivatives seems to be limited to just functions with two variables.

Please help.
Thank you very much.

Alfred Leick

[LucMeekes]

What version of Mathcad, or Prime are you using.

And please attach the (or at least, a) worksheet showing your problem.

Success!
Luc

[AlfredLeick]

I am using Prime 10.0.0

Thanks

[LucMeekes]

I think you've found (yet another) bug in Prime concerning functions with more variables.

This is Prime 9:

This is Prime 10:

You should file a bug report to PTC regarding this.

Prime 11 is supposed to be coming out soon, and we can only hope that it is fixed there.

In the mean time you could use Prime 9 instead of 10, because the bug is not in there.

I pretty confident that your license for Prime 10 allows you to also run Prime 9 (and 8 and 7). So if you have Prime 9 on you machine, use that.

If you don't, consider installing it. Note that you can have several versions of Prime installed and running on your computer, in parallel.

The trouble is that in order to install Prime 9 you first have to de-install Prime 10, because versions of Prime can only be installed in sequential order.

You should be able to download installation sources for previous versions of Prime here: https://support.ptc.com/support/mathcad_downloads.htm

After de-installing Prime 10, install the one(s) you need, and finally Prime 10 and for each of them point to the very same license file that you got for Prime 10.

Success!

Luc

[LucMeekes]

Ah, just found out that the bug is known, and fixed in Prime 10.0.1.0. For info: https://www.ptc.com/en/support/article/CS418413

If you are a licensed user you should be able to download that and install it . As this is a minor release, it will probably replace your 10.0.0.0.

Success!
Luc