[GRASS-user] Uploading NumPy array as a new column to a vector map

[César Augusto Ramírez Franco]

Greetings,

I have a municipality polygon layer with a poverty index (percent) and a
population count, I'm multiplying them to visualize the vulnerability for
each municipality, due to the distribution of that new variable I want to
compute the logarithm, which is not possible in sqlite, so I tried reading
the column with numpy and issuing a np.log10(). I'm happy with the result,
but how can I get this new numpy array to a new column in the vector map in
a simple way?

This is what I already have:

#!/usr/bin/env python

import grass.script as gs
import numpy as np
import matplotlib.pyplot as plt

nbi_pob = np.array(gs.vector_db_select("muniant", columns =
"nbi_pob")["values"].values()).astype(float).squeeze()

plt.hist(nbi_pob)
plt.show()

log_nbi_pob = np.log10(nbi_pob)

plt.hist(log_nbi_pob)
plt.show()

I'm trying to introduce this kind of analysis to students who are not
familiar nor proficient with programming (this is an GIS introductory
course) so the numpy bit is already complex enough to them, and I'd like to
avoid using for loops with cursors to achieve this.

Is there a simple solution to this?

-- 
*César Augusto Ramírez Franco*
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