scale -- the scaling: scale < 0 -> the absolute maximum weight is used as maximum scale
                      scale = double -> this is the maximum scale

from rdkit import Chem
from rdkit.Chem import Draw, rdPartialCharges
from rdkit.Chem.Draw import SimilarityMaps
import io
from PIL import Image
import rdkit

print(rdkit.__version__)


def show_png(data):
    bio = io.BytesIO(data)
    img = Image.open(bio)
    return img

atorvastatin = Chem.MolFromSmiles(
    "O=C(O)C[C@H](O)C[C@H](O)CCn2c(c(c(c2c1ccc(F)cc1)c3ccccc3)C(=O)Nc4ccccc4)C(C)C"
)
Draw.MolsToGridImage((atorvastatin,), molsPerRow=1)

rdPartialCharges.ComputeGasteigerCharges(atorvastatin)
chgs = [x.GetDoubleProp("_GasteigerCharge") for x in atorvastatin.GetAtoms()]

d = Draw.MolDraw2DCairo(400, 400)
SimilarityMaps.GetSimilarityMapFromWeights(atorvastatin, chgs, draw2d=d)
d.FinishDrawing()
show_png(d.GetDrawingText())

d = Draw.MolDraw2DCairo(400, 400)
SimilarityMaps.GetSimilarityMapFromWeights(atorvastatin, chgs, draw2d=d, scale=1000.0)
d.FinishDrawing()
show_png(d.GetDrawingText())

d = Draw.MolDraw2DCairo(400, 400)
SimilarityMaps.GetSimilarityMapFromWeights(atorvastatin, chgs, draw2d=d, scale=0.01)
d.FinishDrawing()
show_png(d.GetDrawingText())