# Finite element model from surfaces with per tissue mesh size¶

A last possibility is to specify a value of characteristic length for each tissue. The process is once again the same.

[ ]:

from shamo import FEM

model = FEM("fem_from_surfaces_lc-tissue", "../../derivatives")

[ ]:

from pathlib import Path

data_path = Path("../../rawdata/surfaces")
tissues = {
f"tissue_{i}": data_path / f"surfaces_tissue{i}.stl" for i in range(1, 8)
}

[ ]:

structure = [
"tissue_1", [
["tissue_2",
["tissue_3"]
],
["tissue_4", [
["tissue_5"],
["tissue_6",
["tissue_7"]
]
]]
]
]


We simply have to define a dictionary containing the values for the characteristic length. If all the tissues do not have a special value, the defaut key must be included.

[ ]:

lc = {
"default": 0.5,
"tissue_2": 0.01,
"tissue_4": 0.01,
}


Finally we pass this dictionary to the mesh_from_surfaces() method.

[ ]:

model.mesh_from_surfaces(tissues, structure, lc)