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-rw-r--r--controller/fw/src/test_pyldpc_utils.py182
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diff --git a/controller/fw/src/test_pyldpc_utils.py b/controller/fw/src/test_pyldpc_utils.py
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+"""Conversion tools."""
+import math
+import numbers
+import numpy as np
+import scipy
+from scipy.stats import norm
+pi = math.pi
+
+
+def int2bitarray(n, k):
+ """Change an array's base from int (base 10) to binary (base 2)."""
+ binary_string = bin(n)
+ length = len(binary_string)
+ bitarray = np.zeros(k, 'int')
+ for i in range(length - 2):
+ bitarray[k - i - 1] = int(binary_string[length - i - 1])
+
+ return bitarray
+
+
+def bitarray2int(bitarray):
+ """Change array's base from binary (base 2) to int (base 10)."""
+ bitstring = "".join([str(i) for i in bitarray])
+
+ return int(bitstring, 2)
+
+
+def binaryproduct(X, Y):
+ """Compute a matrix-matrix / vector product in Z/2Z."""
+ A = X.dot(Y)
+ try:
+ A = A.toarray()
+ except AttributeError:
+ pass
+ return A % 2
+
+
+def gaussjordan(X, change=0):
+ """Compute the binary row reduced echelon form of X.
+
+ Parameters
+ ----------
+ X: array (m, n)
+ change : boolean (default, False). If True returns the inverse transform
+
+ Returns
+ -------
+ if `change` == 'True':
+ A: array (m, n). row reduced form of X.
+ P: tranformations applied to the identity
+ else:
+ A: array (m, n). row reduced form of X.
+
+ """
+ A = np.copy(X)
+ m, n = A.shape
+
+ if change:
+ P = np.identity(m).astype(int)
+
+ pivot_old = -1
+ for j in range(n):
+ filtre_down = A[pivot_old+1:m, j]
+ pivot = np.argmax(filtre_down)+pivot_old+1
+
+ if A[pivot, j]:
+ pivot_old += 1
+ if pivot_old != pivot:
+ aux = np.copy(A[pivot, :])
+ A[pivot, :] = A[pivot_old, :]
+ A[pivot_old, :] = aux
+ if change:
+ aux = np.copy(P[pivot, :])
+ P[pivot, :] = P[pivot_old, :]
+ P[pivot_old, :] = aux
+
+ for i in range(m):
+ if i != pivot_old and A[i, j]:
+ if change:
+ P[i, :] = abs(P[i, :]-P[pivot_old, :])
+ A[i, :] = abs(A[i, :]-A[pivot_old, :])
+
+ if pivot_old == m-1:
+ break
+
+ if change:
+ return A, P
+ return A
+
+
+def binaryrank(X):
+ """Compute rank of a binary Matrix using Gauss-Jordan algorithm."""
+ A = np.copy(X)
+ m, n = A.shape
+
+ A = gaussjordan(A)
+
+ return sum([a.any() for a in A])
+
+
+def f1(y, sigma):
+ """Compute normal density N(1,sigma)."""
+ f = norm.pdf(y, loc=1, scale=sigma)
+ return f
+
+
+def fm1(y, sigma):
+ """Compute normal density N(-1,sigma)."""
+
+ f = norm.pdf(y, loc=-1, scale=sigma)
+ return f
+
+
+def bitsandnodes(H):
+ """Return bits and nodes of a parity-check matrix H."""
+ if type(H) != scipy.sparse.csr_matrix:
+ bits_indices, bits = np.where(H)
+ nodes_indices, nodes = np.where(H.T)
+ else:
+ bits_indices, bits = scipy.sparse.find(H)[:2]
+ nodes_indices, nodes = scipy.sparse.find(H.T)[:2]
+ bits_histogram = np.bincount(bits_indices)
+ nodes_histogram = np.bincount(nodes_indices)
+
+ return bits_histogram, bits, nodes_histogram, nodes
+
+
+def incode(H, x):
+ """Compute Binary Product of H and x."""
+ return (binaryproduct(H, x) == 0).all()
+
+
+def gausselimination(A, b):
+ """Solve linear system in Z/2Z via Gauss Gauss elimination."""
+ if type(A) == scipy.sparse.csr_matrix:
+ A = A.toarray().copy()
+ else:
+ A = A.copy()
+ b = b.copy()
+ n, k = A.shape
+
+ for j in range(min(k, n)):
+ listedepivots = [i for i in range(j, n) if A[i, j]]
+ if len(listedepivots):
+ pivot = np.min(listedepivots)
+ else:
+ continue
+ if pivot != j:
+ aux = (A[j, :]).copy()
+ A[j, :] = A[pivot, :]
+ A[pivot, :] = aux
+
+ aux = b[j].copy()
+ b[j] = b[pivot]
+ b[pivot] = aux
+
+ for i in range(j+1, n):
+ if A[i, j]:
+ A[i, :] = abs(A[i, :]-A[j, :])
+ b[i] = abs(b[i]-b[j])
+
+ return A, b
+
+
+def check_random_state(seed):
+ """Turn seed into a np.random.RandomState instance
+ Parameters
+ ----------
+ seed : None | int | instance of RandomState
+ If seed is None, return the RandomState singleton used by np.random.
+ If seed is an int, return a new RandomState instance seeded with seed.
+ If seed is already a RandomState instance, return it.
+ Otherwise raise ValueError.
+ """
+ if seed is None or seed is np.random:
+ return np.random.mtrand._rand
+ if isinstance(seed, numbers.Integral):
+ return np.random.RandomState(seed)
+ if isinstance(seed, np.random.RandomState):
+ return seed
+ raise ValueError('%r cannot be used to seed a numpy.random.RandomState'
+ ' instance' % seed)