UPDATE:
After thinking about it, the most efficient method for you to transform the coordinates is probably to not use apply but to use the column array.
from pyproj import Proj
pp = Proj(proj='utm',zone=10,ellps='WGS84', preserve_units=False)
xx, yy = pp(My_data["LON"].values, My_data["LAT"].values)
My_data["X"] = xx
My_data["Y"] = yy
Using Transformer
from pyproj import Transformer
trans = Transformer.from_crs(
"epsg:4326",
"+proj=utm +zone=10 +ellps=WGS84",
always_xy=True,
)
xx, yy = trans.transform(My_data["LON"].values, My_data["LAT"].values)
My_data["X"] = xx
My_data["Y"] = yy
ORIGINAL ANSWER:
This answer here is great: https://gis.stackexchange.com/a/334276/144357
The solution below is for the purposes of understanding the root of the problem a bit better.
Your code in its current form re-constructs the Proj object with each iteration. This is a costly operation and is why the pyproj.Transformer object was created. It assists with repeated transformations because you don't have to re-create it each time (see: https://pyproj4.github.io/pyproj/stable/advanced_examples.html#repeated-transformations).
So, to avoid re-creating the Proj object, you can modify your code like so:
from pyproj import Proj
from functools import partial
p = Proj(proj='utm',zone=10,ellps='WGS84', preserve_units=False)
def impartial_rule(row, proj):
x,y = proj(row["LON"], row["LAT"])
return pd.Series({"X": x , "Y": y})
rule = partial(impartial_rule, proj=p)
My_data = My_data.merge(My_data.apply(rule, axis=1), left_index= True, right_index= True)
This should improve your performance.
Here is the equivalent using the pyproj.Transformer:
from pyproj import Transformer
from functools import partial
trans = Transformer.from_crs(
"epsg:4326",
"+proj=utm +zone=10 +ellps=WGS84",
always_xy=True,
)
def impartial_rule(row, proj):
x,y = proj(row["LON"], row["LAT"])
return pd.Series({"X": x , "Y": y})
rule = partial(impartial_rule, proj=trans.transform)
My_data = My_data.merge(My_data.apply(rule, axis=1), left_index= True, right_index= True)
Hopefully this is helpful. Good luck!
Also, I would recommend reading this about Proj: https://pyproj4.github.io/pyproj/stable/gotchas.html#proj-not-a-generic-latitude-longitude-to-projection-converter
