open mod and data Files

[Lena Porschen]

Hello,

i tried to install ampl on macOS. I download the ampl folder and put amplide in, but when i want to open some data or mod files from your page
i get the error „An error has occurred. See error log for more details. java.lang.NullPointerExeception“.
Can someone help to find a solution ?

Best regards Lena Porschen

[AMPL Google Group]

Dear Lena Porschen,

Can you confirm what is the macOS version of your machine?

We are investigating the side-effects of the macOS 11.0 Big Sur update on
AMPL IDE. In that version of macOS, AMPL IDE will display errors messages
similar to the one you described.

As a temporary fix, you may try using the command-line version
of AMPL. We give here an example of how to start command-line AMPL on macOS,
and then we explain how to adjust the example so that it works on your
particular computer.

EXAMPLE: Find the application named "ampl" (with black square icon) and
double-click it. A new command window will appear, containing various
messages and ending with an "ampl:" prompt. The last few lines will have
this form:

/Users/yourname/Desktop/AMPL/ampl.macosx64/ampl; exit;
Your-MacBook:~ yourname$ /Users/yourname/Desktop/AMPL/ampl.macosx64/ampl;
exit;
ampl:

At the "ampl:" prompt, enter a command like this:

cd /Users/yourname/Desktop/AMPL/ampl.macosx64;

Then you can enter regular AMPL commands at the "ampl:" prompts, in the same
way that you do in the AMPL IDE console window. To create your AMPL files,
you will need to use a separate plain-text editor, such as the macOS
TextEdit application. Please note: Files should be placed in the same folder
as the "ampl" application that you double-clicked.

ADJUSTING THE EXAMPLE FOR YOUR COMPUTER: Instead of
/Users/yourname/Desktop/AMPL/ampl.macosx64, you will see some other folder
path in the command window message. Use that path in your AMPL "cd" command.
(Be sure to drop "ampl" from the end of the path when you type it.)

SETTING A SOLVER: If your "solve" command is rejected with a "Cannot find . . ."
message, you will need to adjust the "option solver" statement. As an example,
if you would have selected the CPLEX solver with "option solver cplex;", you will
need to say instead

option solver './cplex';

It is similar for other solvers; just substitute the solver's name for cplex above.

Hope this helps!
Best regards,

--
Nicolau Santos
am...@googlegroups.com

{#HS:1347980217-94285#}

[AMPL Google Group]

Dear Lena Porschen,

I'm writing this email to inform you we have an updated version of AMPL IDE (3.6.4) compatible with macOS Big Sur available at:

https://ampl.com/dl/nfbvs/experimental/amplide/amplide.mac64.tgz

Download and extract the file and move the resulting amplide.app to the same folder where you have AMPL.
Note that you have to run (double click) the script ampl.command afterwards, otherwise you will get the message:

"Amplide" is damaged and can't be opened.
You should move it to the Trash.

You should have "ampl.command" in the folder where you have the AMPL executable and solvers. If you don't have "ampl.command" available download the following file: https://ampl.com/demo/amplide.macosx64.tgz. Move it out of the Downloads folder and unpack it. Find "ampl.command" inside and drag it into the same folder as the AMPL executable.
Afterwards you will need to:

• Control-click "ampl.command" and select Open in the menu that pops up.
• If a box containing a warning message ("macOS cannot verify the developer") pops up, click Open in that box.
• An ampl.command Terminal window will appear. After a few seconds, you will see "ampl:" in the last line of in the window. You can then terminate that window (by clicking the red button at the upper left).

This version will replace the currently available in the main AMPL repositories in the next days.
Please let us know if you find any issues with this version of AMPL IDE.

Best regards,

Nicolau

--
Nicolau Santos
am...@googlegroups.com

{#HS:1347980217-94285#}

On Tue, Nov 24, 2020 at 7:30 PM UTC, AMPL Modeling Language <am...@googlegroups.com> wrote: