Morpho | create Envimet 2.5D and 3D models | Topic Modeling library

I've tried to create a 3D mesh looking like a cylinder and then cut it in half as following:

In my python project, I need to extract REFERENCES from pdf research papers. I'm using PyPDF2 to read pdf and extract text from it like this.

I am doing work a geometric morphometric dataset of biological specimens with two dimensional Cartesian coordinates (i.e., landmarks). Part of my interest with this dataset is to produce a data frame of distances between important landmarks and angles between landmark vectors with homologous coordinates across all specimens for further comparison. Distances between points have not been a problem, but I have been running into problems when I have tried to calculate angles in each of my specimens.

I am trying to find a way to calculate the angle between line vectors representing the same angle on a series of specimens at once (the vectors describe a feature with biological significance that is present in all specimens across my dataset). The R package I use to manipulate the morphometric data outputs the landmarks as a three-dimensional object of class array() where rows are landmarks, columns are the dimensions of the coordinate, and the third dimension is the specimen. Here are the landmark coordinates for the three specimens in the sample data presented here.