@ddw_music sudo installs gem for you. It installs it better somehow and it actually works. I tried all the other instructions and it never worked at all . Maybe I was a beginner, but im not even going to try it again for the 20th time.

no it never works easily I was learning pd for a year before I ever got it to work. I only ever got gem to work from sudo . the cia people dont even do anything someone else installs it for them

try installing it on another computer the same way and maybe you can see it there .

bezier curve system and pixel pen

https://patchstorage.com/bezier-curve-and-pixel-pen-pd-vanilla-gem/

you make a pd "sub-patch" object. you put object and type pd and then a space and a name.. and off click so then you are immediately inside the sub patch page. then you right click for properties. you make it yes graph-on parent. and then you move it with margin in the properties window and the size is also in the properties window. then if you go to the above page parent page and you see the object box you made except its larger according to the properties you entered on the inside page.

you put .wav files into an array which is a list . and then you ask for numbers from the array with tabread will give you one number from the list. which they call a sample. etc sample rate...

here I found this page https://forum.pdpatchrepo.info/topic/13087/abstractions-as-creation-arguments-things-i-wish-i-knew-before

I added a bit for extra explaination after looking quickly

mine says divde by zero detected.

because I dont understand expr really, I only do everything without them. which is the same thing. probably - it just looks different. If you write out all of them in english Id try and do it regular and maybe learn it at the same time. write it up and ill try it. otherwise your file is missing "output" object I dont know what library it is. it means dac~ ?

this has a bunch of stuff it uses an older version of pd sometimes but you can work around it , they changed a couple object names.
http://pd-tutorial.com/
http://pd-tutorial.com/english/ch03s07.html