How to insert z values onto x,y coordinates? - python-3.x

Question

I have three list, which has some repeated values. I am using them as x and y coordinates. Thus, my third list is corresponds to the values that I want to plot as a heatmap.
For now, I can assign the values of z for only one list, how can I make a for loop to do the same for the rest of the grid?
x = [1,1,1,2,2,2,3,3,3]
y = [1,2,3,1,2,3,1,2,3]
z = [5.9617e-09,6.3562e-09,6.819e-09,7.3562e-09,7.989e-09,8.6735e-
09,9.3898e-09,1.0139e-08,1.0912e-08,1.0912e-08]
xs = len(set(x))
ys = len(set(y))
grid = []
counter = 0
for row in range(ys):
rows = [] # creating the rows on the grid
if len(rows) < ys: # I want to loop over ys and assign the values os z to each coordinate
grid.append(z[counter])
counter = counter+1
print(grid)
Once I have a 2d array, then I can use the heatmap to plot it nicely.

Answer 1

The easiest way is to use numpy:
In [1]: z = [5.9617e-09,6.3562e-09,6.819e-09,7.3562e-09,
7.989e-09,8.6735e-09,9.3898e-09,1.0139e-08,
1.0912e-08,1.0912e-08]
In [2]: len(z)
Out[2]: 10
In [3]: import numpy as np
Ten numbers don't fit in a 3x3 grid, so skip the last one.
In [4]: nz = np.array(z[:-1])
Out[4]:
array([5.9617e-09, 6.3562e-09, 6.8190e-09, 7.3562e-09, 7.9890e-09,
8.6735e-09, 9.3898e-09, 1.0139e-08, 1.0912e-08])
In [5]: nz.reshape((3,3))
Out[5]:
array([[5.9617e-09, 6.3562e-09, 6.8190e-09],
[7.3562e-09, 7.9890e-09, 8.6735e-09],
[9.3898e-09, 1.0139e-08, 1.0912e-08]])
A plain Python solution using itertools and functools:
In [6]: import itertools as it
...: import functools as ft
In [7]: def chunked(iterable, n): # {{{1
...: def take(n, iterable):
...: return list(it.islice(iterable, n))
...: return iter(ft.partial(take, n, iter(iterable)), [])
...:
In [8]: list(chunked(z[:-1], 3))
Out[8]:
[[5.9617e-09, 6.3562e-09, 6.819e-09],
[7.3562e-09, 7.989e-09, 8.6735e-09],
[9.3898e-09, 1.0139e-08, 1.0912e-08]]