Create model only if it doesn't exist

My script has this structure :

sas='Model'; new=new_system('sas') open_system('sas')

[...]

save_system('sas') close_system('sas')

Now the questio is:

I can need to work more on the system that I close, I can need to add other blocks. I would like to reach this purpose

1- Open system that I had closed and saved. Now if I run the script the second time, It says "A system named 'sas'already exists. Is there a function similar to fopen for files, so that I could delete new_system?

[Chiara]

idea: if I declare a variable set to 0 when I run the script for the first time, then I increment to 1. I could close creation of system in if-else code, so when the variable is 1, it doesn't creat but It opens!

Answer 1

[Azzi Abdelmalek]

if isempty(which('Model.mdl'))
  new=new_system('Model')
end
open_system('Model')

[Chiara]

thank you very much! I used the same structure, even to use other variables declared when I run the script the first time.

[Kaustubha Govind]

I would make that:

isempty(which('Model.mdl')) && isempty(which('Model.slx'))

Since newer versions of Simulink use the .slx extension for models.

You can alternatively also use the exist function.