Trying to run turbo_encode

[sankalpmittal1911-BitSian]

import numpy as np
import commpy.channelcoding as cx
import commpy.channelcoding.convcode as cc
memory = np.array([2])
g_matrix = np.array([[5, 7]])
trellis = cc.Trellis(memory, g_matrix)
trellis.k =1 
trellis.n = 2
trellis.number_states=0
trellis.number_inputs = 0
trellis.total_memory = 0
x = np.array([1,0,1,0,1,1])
x=np.array(x);
print(cx.turbo_encode(x,trellis,trellis,cx.RandInterlv))

I get this error:

File "C:\Users\sankalp.1\AppData\Local\Programs\Python\Python37\lib\site-packages\commpy\utilities.py", line 50, in dec2bitarray
   bitarray[bit_width - i - 1] = int(binary_string[length - i - 1])
IndexError: index -1 is out of bounds for axis 0 with size 0

Can anyone help me figure out how to eliminate this error? It seems to be working fine in conv_encode.

Thank you.

[jeichenhofer]

I am also interested in an example for constructing correct trellis objects using this interface. I haven't encountered this specific error, but I am struggling to understand the format and specification of this library's representation of the trellis. @veeresht you were able to point me in the right direction on my last question, can you provide any insight here?

[BastienTr]

Hi @jeichenhofer,
I can't help you on turbocodes as I've never had a look to this module. However, regarding to the format and specifications of the trellis, you should have a look to conv_encode_decode example file. Be sure to use the github version as the pip version doesn't curretly have all the funtion required to run this file.