Convert list of tuples in list of lists ( NP array )

Question

i have a array response from a api and i got this poly:

poly = [(0,525),(961,525),(961,1003),(0,1003)]

i need to multiply each item for 0.35, them my code was it:

poly = ak.Array(poly) * (35/100)

i got a <class 'awkward1.highlevel.Array'> object then i changed it to a np array

poly = np.array(poly)

but this is converted to a wrong format

[(  0.  , 183.75) (336.35, 183.75) (336.35, 351.05) (  0.  , 351.05)]

i need that my resultant array to be this as np.array int32:

[[0, 184], [336, 184], [336, 351], [0, 351]]

some one can help me please?

`np.array(poly)` gives me the expected 2D array. Why do you need `ak`? Also, you can try: `ak.Array(np.array(poly) * .35)` — Quang Hoang, Aug 26 '20 at 12:58
becouse i need that firstresult to be a awk object to my function works — Jasar Orion, Aug 26 '20 at 12:59
yes, its a array of tutles then i need to change its proportions and convert to array of arrays — Jasar Orion, Aug 26 '20 at 13:15

Nikhil Kumar · Answer 1 · 2020-08-26T13:38:04.920

Each of the subarrays in your poly array have type numpy.void. Directly converting the numpy.void into a numpy.array didn't work, i.e., it was not giving the shape of the array that you wanted.

Iterate over each of the numpy.void arrays, convert them to tuples and then convert them to numpy.arrays, while typecasting the floats to np.int32s.

This works, as explained above:

import numpy as np
import awkward1.highlevel as ak

poly = [(0,525),(961,525),(961,1003),(0,1003)]
poly = ak.Array(poly) * (35/100)
poly = np.array(poly)

# Initializing a list, as NumPy was throwing some error that I haven't resolved.
poly_list = list()
for i, tup in enumerate(poly.copy()):
    # Converting to tuple and then to np.array to fix an error.
    poly_list.append(np.array(tuple(tup)))

# Converting back to a NumPy array.
poly = np.array(poly_list)

print(poly)

# Rounding and converting elements to np.int32 type
poly = poly.astype(np.int32)

I'm not familiar with the awkward1 package, so this may be a hack solution. But it works.

@Jasar Orion It was throwing an error. This works now. – Nikhil Kumar Aug 26 '20 at 13:38 — Nikhil Kumar, Aug 26 '20 at 13:38

score 0 · Answer 2 · answered Aug 26 '20 at 13:21

i did ^^

import numpy as np
import awkward1 as ak




poly = [(0,525),(961,525),(961,1003),(0,1003)]
poly = ak.Array(poly) * (35/100)
print(poly)
print(type(poly))



poly = np.array(poly)
poly = [[int(i), int(j)] for i, j in poly]

print(poly)
print(type(poly))

i found this solution talking to a friend.

Convert list of tuples in list of lists ( NP array )

2 Answers2