Probability Distribution not included in UQLab

Hi, I am Judah.
Currently facing a challenge with my data.
After using the plotting too in Matlab, it is clear that my data is a fretchet distribution as its K value is less than 0. I would like to know how to input a distribution type (fretchet or GEV) that is not included in UQLab given its parameters.

Dear @Judah

In the manual on inputs there is a separate section on how to create and use your own distributions. See section 2.7:

I hope this answers your questions.

Best regards

Thank you this really helps