def build_J(cells, spacing, r_max=R_MAX):
'''Build the J matrix for the given circuit. Restricts the interaction
distance to r_max but does not apply any adjacency contraints'''
N = len(cells)
# contruct connectivvity matrix
J = np.zeros([N, N], dtype=float)
DR = r_max*spacing
for i,j in combinations(range(N), 2):
Ek = getEk(cells[i], cells[j], DR=DR)
if Ek:
J[i,j] = J[j,i] = Ek
# remove very weak interactions
J = J*(np.abs(J) >= np.max(np.abs(J)*EK_THRESH))
return J
def zone_cells(cells, spacing, show=False):
'''Split cells into clock zones. Distinguishes disjoint zones with the
same zone index'''
N = len(cells) # number of cells
# construct connectivity matrix
J = np.zeros([N, N], dtype=float)
DR = R_MAX * spacing
for i in xrange(N - 1):
for j in xrange(i + 1, N):
Ek = getEk(cells[i], cells[j], DR=DR)
if Ek:
J[i, j] = Ek
J[j, i] = Ek
# remove very weak interactions
J = J * (np.abs(J) >= np.max(np.abs(J) * EK_THRESH))
# make full cell connectivity Graph
G = nx.Graph(J)
# if show:
# plt.figure(0)
# plt.clf()
# nx.draw_graphviz(G)
# plt.show()
# get indices for each clock index
clk = [cell['clk'] for cell in cells]
clk_ind = list(set(clk)) # will sort by default
inds = [[i for i, x in enumerate(clk) if x == ind] for ind in clk_ind]
# split graph into sub-graphs with the same clock indices
sub_G = {ind: G.subgraph(inds[ind]) for ind in clk_ind}
# split disconnected components for each label graph
sub_ind = {
ind: list(nx.connected_components(sub_G[ind]))
for ind in clk_ind
}
## find zone order
# create abstract zone connectivity graph
G = nx.DiGraph()
# nodes
for clk in clk_ind:
for i in xrange(len(sub_ind[clk])):
key = (clk, i)
G.add_node(key, inds=sub_ind[clk][i])
# edges
for clk in clk_ind:
adj_clk = 3 if clk == 0 else clk - 1
if not adj_clk in sub_ind:
continue
for i in xrange(len(sub_ind[clk])):
k1 = (clk, i)
for j in xrange(len(sub_ind[adj_clk])):
k2 = (adj_clk, j)
if np.any(J[G.node[k1]['inds'], :][:, G.node[k2]['inds']]):
G.add_edge(k2, k1)
# if show:
# plt.figure(1)
# plt.clf()
# nx.draw_graphviz(G)
# plt.show()
# find input nodes, have no predecessors
predecs = {n: len(G.predecessors(n)) for n in G.nodes_iter()}
inputs = [ky for ky, val in predecs.iteritems() if val == 0]
# expand from inputs
visited = {key: False for key in G.nodes()}
nodes = inputs
order = [nodes]
while nodes:
new_nodes = set()
for node in nodes:
new_nodes.update(G.successors(node))
visited[node] = True
# remove already visited nodes from new nodes
new_nodes = [node for node in new_nodes if not visited[node]]
nodes = new_nodes
if nodes:
order.append(nodes)
# find feedback interactions
feedback = {}
for n in G.nodes_iter():
for p in G.predecessors(n):
pshell = 0
nshell = 0
pzone = 0
nzone = 0
for shell in order:
if p in shell:
pshell = order.index(shell)
pzone = shell.index(p)
if n in shell:
nshell = order.index(shell)
nzone = shell.index(n)
if pshell > nshell:
if (pshell, pzone) in feedback:
feedback[(pshell, pzone)].append((nshell, nzone))
else:
feedback[(pshell, pzone)] = [(nshell, nzone)]
# reformat order list to contain zone indices
form_func = lambda n: sub_ind[n[0]][n[1]]
order = [[form_func(zone) for zone in shell] for shell in order]
return order, J, feedback
def zone_cells(cells, spacing):
'''Split cells into clock zones. Distinguishes disjoint zones with the
same zone index'''
N = len(cells) # number of cells
# construct connectivity matrix
J = np.zeros([N, N], dtype=float)
DR = R_MAX*spacing
for i in range(N-1):
for j in range(i+1, N):
Ek = getEk(cells[i], cells[j], DR=DR)
if Ek:
J[i, j] = -Ek
J[j, i] = -Ek
# remove very weak interactions
J = J * (np.abs(J) >= np.max(np.abs(J)*EK_THRESH))
# make full cell connectivity Graph
G = nx.Graph(J)
# get indices for each clock index
clk = [cell['clk'] for cell in cells]
clk_ind = list(set(clk)) # will sort by default
inds = [[i for i, x in enumerate(clk) if x == ind] for ind in clk_ind]
# split graph into sub-graphs with the same clock indices
sub_G = {ind: G.subgraph(inds[ind]) for ind in clk_ind}
# split disconnected components for each label graph
sub_ind = {ind: list(nx.connected_components(sub_G[ind]))
for ind in clk_ind}
## find zone order
# create abstract zone connectivity graph
G = nx.DiGraph()
# nodes
for clk in clk_ind:
for i in range(len(sub_ind[clk])):
key = (clk, i)
G.add_node(key, inds=sub_ind[clk][i])
# edges
for clk in clk_ind:
adj_clk = 3 if clk == 0 else clk-1
if not adj_clk in sub_ind:
continue
for i in range(len(sub_ind[clk])):
k1 = (clk, i)
for j in range(len(sub_ind[adj_clk])):
k2 = (adj_clk, j)
if np.any(J[G.node[k1]['inds'], :][:, G.node[k2]['inds']]):
G.add_edge(k2, k1)
# find input nodes, have no predecessors
predecs = {n: len(list(G.predecessors(n))) for n in G}
inputs = [ky for ky, val in predecs.iteritems() if val == 0]
# expand from inputs
visited = {key: False for key in G.nodes()}
nodes = inputs
order = [nodes]
while nodes:
new_nodes = set()
for node in nodes:
new_nodes.update(G.successors(node))
visited[node] = True
# remove already visited nodes from new nodes
new_nodes = [node for node in new_nodes if not visited[node]]
nodes = new_nodes
if nodes:
order.append(nodes)
# find feedback interactions
feedback = {}
for n in G:
for p in G.predecessors(n):
pshell = 0
nshell = 0
pzone = 0
nzone = 0
for shell in order:
if p in shell:
pshell = order.index(shell)
pzone = shell.index(p)
if n in shell:
nshell = order.index(shell)
nzone = shell.index(n)
if pshell > nshell:
if (pshell,pzone) in feedback:
feedback[(pshell,pzone)].append((nshell,nzone))
else:
feedback[(pshell,pzone)] = [(nshell,nzone)]
# reformat order list to contain zone indices
form_func = lambda n: sub_ind[n[0]][n[1]]
order = [[form_func(zone) for zone in shell] for shell in order]
return order, J, feedback