Netlist extractor YAML#

Any component can extract its netlist with get_netlist

While gf.read.from_yaml converts a YAML Dict into a Component

get_netlist converts Component into a YAML Dict

import gdsfactory as gf
import yaml
c = gf.components.mzi()
c.plot()
../_images/f6a7df9b42235832867438ccfd5b16e50986e57a468880992c11b55a579c3c91.png
c.plot_netlist()
<networkx.classes.graph.Graph at 0x7ff4a9568650>
../_images/1aef4e6095723fc8c40259d4680fe2e6abfc75e4095cf8a006e2b19b17deb3d9.png
c = gf.components.ring_single()
c.plot()
../_images/8bb7002268fd65e70c914bfffa7e5bd83ee13656828a2f8b69172768bf16e53e.png
c.plot_netlist()
<networkx.classes.graph.Graph at 0x7ff4a940c650>
../_images/4e301c8f22d8841328d9a7958e270e6fd430cdb7025e4fdeee082f6823266a8c.png
n = c.get_netlist()
netlist_string = c.write_netlist(n)
n = yaml.safe_load(netlist_string)
i = list(n["instances"].keys())
i
['bend_euler_R10_A90_P0p5_2f1f5c6d_10000_11300',
 'bend_euler_R10_A90_P0p5_2f1f5c6d_m4000_21300',
 'coupler_ring_G0p2_R10_L_9871ac59_0_0',
 'straight_L0p6_N2_CSstrip_WNone_10000_11300',
 'straight_L0p6_N2_CSstrip_WNone_m14000_10700',
 'straight_L4_N2_CSstrip_WNone_0_21300']
instance_name0 = i[0]
n["instances"][instance_name0]["settings"]
{'allow_min_radius_violation': False,
 'angle': 90,
 'cross_section': 'strip',
 'layer': None,
 'npoints': None,
 'p': 0.5,
 'radius': 10,
 'width': None,
 'with_arc_floorplan': True}

Instance names#

By default get netlist names each instance with the name of the reference

@gf.cell
def mzi_with_bend_automatic_naming():
    c = gf.Component()
    mzi = c.add_ref(gf.components.mzi())
    bend = c.add_ref(gf.components.bend_euler())
    bend.connect("o1", mzi.ports["o2"])
    return c


c = mzi_with_bend_automatic_naming()
c.plot_netlist()
<networkx.classes.graph.Graph at 0x7ff4a9407a90>
../_images/0ec4c3594a7582430f80fb1cd467e0e58a744da3e68eb1f1bc2be722b2463973.png
@gf.cell
def mzi_with_bend_deterministic_names_using_alias():
    c = gf.Component()
    mzi = c.add_ref(gf.components.mzi(), alias="my_mzi")
    bend = c.add_ref(gf.components.bend_euler(), alias="my_bend")
    bend.connect("o1", mzi.ports["o2"])
    return c


c = mzi_with_bend_deterministic_names_using_alias()
c.plot_netlist()
/home/runner/work/gplugins/gplugins/.venv/lib/python3.11/site-packages/gdsfactory/component.py:679: UserWarning: alias is deprecated, use name instead
  warnings.warn("alias is deprecated, use name instead")
<networkx.classes.graph.Graph at 0x7ff4a93858d0>
../_images/671aa514e2932777bb2a23d4dabddb6f0947fce138422ec14a970216da1e4c6a.png
c = gf.components.mzi()
c.plot()
../_images/f6a7df9b42235832867438ccfd5b16e50986e57a468880992c11b55a579c3c91.png
c = gf.components.mzi()
n = c.get_netlist()
print(c.get_netlist().keys())
dict_keys(['nets', 'instances', 'placements', 'ports', 'name'])
c.plot_netlist()
<networkx.classes.graph.Graph at 0x7ff4a9363d50>
../_images/1aef4e6095723fc8c40259d4680fe2e6abfc75e4095cf8a006e2b19b17deb3d9.png
n.keys()
dict_keys(['nets', 'instances', 'placements', 'ports', 'name'])

warnings#

Lets make a connectivity error, for example connecting ports on the wrong layer

@gf.cell
def mmi_with_bend():
    c = gf.Component()
    mmi = c.add_ref(gf.components.mmi1x2(), alias="mmi")
    bend = c.add_ref(gf.components.bend_euler(layer=(2, 0)), alias="bend")
    bend.connect("o1", mmi.ports["o2"], allow_layer_mismatch=True)
    return c


c = mmi_with_bend()
c.plot()
../_images/b3b348b27cbfa3cc7deef6882cd640b183976f375f3a9bc776037c201aaea874.png
n = c.get_netlist()
print(n["warnings"])
{'optical': {'unconnected_ports': ({'ports': ('mmi,o1', 'mmi,o3', 'bend,o2'), 'values': ((-10000, 0), (15500, -625), (25500, 10625)), 'message': '3 unconnected optical ports!'},)}}
c.plot_netlist()
<networkx.classes.graph.Graph at 0x7ff4aad59550>
../_images/21469b8cbda0f054911ac033b89e60b83c083a7a20f0503a1df84c9be871031f.png

get_netlist_recursive#

When you do get_netlist() for a component it will only show connections for the instances that belong to that component. So despite having a lot of connections, it will show only the meaningful connections for that component. For example, a ring has a ring_coupler. If you want to dig deeper, the connections that made that ring coupler are still available.

get_netlist_recursive() returns a recursive netlist.

c = gf.components.ring_single()
c.plot()
../_images/8bb7002268fd65e70c914bfffa7e5bd83ee13656828a2f8b69172768bf16e53e.png
c.plot_netlist()
<networkx.classes.graph.Graph at 0x7ff4a90d3a10>
../_images/4e301c8f22d8841328d9a7958e270e6fd430cdb7025e4fdeee082f6823266a8c.png
c = gf.components.ring_double()
c.plot()
../_images/6afb4edc23a805f650e649d062015e2b935fd3eb6ea9bbd4db0e6bf5cfca62ba.png
c.plot_netlist()
<networkx.classes.graph.Graph at 0x7ff4a912fe90>
../_images/bd7e178af256ceea176e95cfdfe8ce83598f3e7d34487453144992bb86cd6ed4.png
c = gf.components.mzit()
c.plot()
../_images/1f448428114e7cdb8d6130b83a6313e032f0bc892416ba850ef5f39d9fad9541.png
c.plot_netlist()
<networkx.classes.graph.Graph at 0x7ff4a9385ed0>
../_images/d31a4ad78070746766a3d8cc77058a88c2089a227038b1968dd9b99a468ffd12.png
coupler_lengths = (10, 20, 30)
coupler_gaps = (0.1, 0.2, 0.3)
delta_lengths = (10, 100)

c = gf.components.mzi_lattice(
    coupler_lengths=coupler_lengths,
    coupler_gaps=coupler_gaps,
    delta_lengths=delta_lengths,
)
c.plot()
../_images/00171495a138214396938e1d045c78907d0438c9ac8dcb86fd9b3ded4afe288b.png
c.plot_netlist()
<networkx.classes.graph.Graph at 0x7ff4a8e50f50>
../_images/3d7798f09e91231225b6448d0ed97593d4bbc98c9feb3ed437a88bf1c991c05e.png
coupler_lengths = (10, 20, 30, 40)
coupler_gaps = (0.1, 0.2, 0.4, 0.5)
delta_lengths = (10, 100, 200)

c = gf.components.mzi_lattice(
    coupler_lengths=coupler_lengths,
    coupler_gaps=coupler_gaps,
    delta_lengths=delta_lengths,
)
c.plot()
../_images/e09c5ebec4f5a583cc686e36ce74e43821c13d6777309a30f9df7e91f1ab16ef.png
n = c.get_netlist()
c.plot_netlist()
<networkx.classes.graph.Graph at 0x7ff4a8e4aa50>
../_images/c6c51e445fdb3454cf5f370703597cbbe03302ba198939abc8a7275ca4f8c5c0.png
n_recursive = c.get_netlist(recursive=True)
n_recursive.keys()
dict_keys(['mzi_lattice_CL10_20_30__8514709c', 'mzi_DL10_LY2_LXNone_Bbe_7eee11eb', 'mzi_DL100_LY2_LXNone_Bb_4ce1f1e6', 'mzi_DL200_LY2_LXNone_Bb_dce7e6c1'])

Placement information is accumulated, and connections and ports are mapped, respectively, to the ports of the unique instances or the component top level ports. This can be plotted:

c.plot_netlist(with_labels=False)  # labels get cluttered
<networkx.classes.graph.Graph at 0x7ff4a8e9a050>
../_images/bc207f63db2396cb7b7765bb92503bed6750bbaebbd6c78a8f7d35fbd4189a48.png

allow_multiple_connections#

The default get_netlist function (also used by default by get_netlist_recurse and get_netlist_flat) can identify more than two ports sharing the same connection through the allow_multiple flag.

For instance, consider a resistor network with one shared node:

import gdsfactory as gf

vdiv = gf.Component()
r1 = vdiv << gf.components.resistance_sheet()
r2 = vdiv << gf.components.resistance_sheet()
r3 = vdiv << gf.get_component(gf.components.resistance_sheet)
r4 = vdiv << gf.get_component(gf.components.resistance_sheet)

r1.connect("pad2", r2.ports["pad1"])
r3.connect("pad1", r2.ports["pad1"])
r4.connect("pad2", r2.ports["pad1"])

r4.drotate(90)

vdiv.plot()
../_images/f7d74a32e157e4bd17877ff0f52054e91af979810609bfec163af66ab662a1c4.png
try:
    vdiv.get_netlist()
except Exception as exc:
    print(exc)
vdiv.get_netlist(allow_multiple=True)
{'nets': ({'p1': 'resistance_sheet_W10_LH_1b3e3b4b_0_0,pad1',
   'p2': 'resistance_sheet_W10_LH_1b3e3b4b_0_m50000,pad2'},
  {'p1': 'resistance_sheet_W10_LH_1b3e3b4b_0_0,pad1',
   'p2': 'resistance_sheet_W10_LH_1b3e3b4b_m100000_m50000,pad1'},
  {'p1': 'resistance_sheet_W10_LH_1b3e3b4b_0_0,pad2',
   'p2': 'resistance_sheet_W10_LH_1b3e3b4b_0_m50000,pad1'},
  {'p1': 'resistance_sheet_W10_LH_1b3e3b4b_0_m50000,pad2',
   'p2': 'resistance_sheet_W10_LH_1b3e3b4b_m100000_m50000,pad1'}),
 'instances': {'resistance_sheet_W10_LH_1b3e3b4b_0_0': {'component': 'resistance_sheet',
   'info': {'resistance': 0},
   'settings': {'width': 10,
    'layers': ('HEATER',),
    'layer_offsets': (0, 0.2),
    'pad': 'via_stack_heater_mtop',
    'pad_size': (50, 50),
    'pad_pitch': 100,
    'ohms_per_square': None,
    'pad_port_name': 'e4'}},
  'resistance_sheet_W10_LH_1b3e3b4b_0_m50000': {'component': 'resistance_sheet',
   'info': {'resistance': 0},
   'settings': {'width': 10,
    'layers': ('HEATER',),
    'layer_offsets': (0, 0.2),
    'pad': 'via_stack_heater_mtop',
    'pad_size': (50, 50),
    'pad_pitch': 100,
    'ohms_per_square': None,
    'pad_port_name': 'e4'}},
  'resistance_sheet_W10_LH_1b3e3b4b_50000_0': {'component': 'resistance_sheet',
   'info': {'resistance': 0},
   'settings': {'width': 10,
    'layers': ('HEATER',),
    'layer_offsets': (0, 0.2),
    'pad': 'via_stack_heater_mtop',
    'pad_size': (50, 50),
    'pad_pitch': 100,
    'ohms_per_square': None,
    'pad_port_name': 'e4'}},
  'resistance_sheet_W10_LH_1b3e3b4b_m100000_m50000': {'component': 'resistance_sheet',
   'info': {'resistance': 0},
   'settings': {'width': 10,
    'layers': ('HEATER',),
    'layer_offsets': (0, 0.2),
    'pad': 'via_stack_heater_mtop',
    'pad_size': (50, 50),
    'pad_pitch': 100,
    'ohms_per_square': None,
    'pad_port_name': 'e4'}}},
 'placements': {'resistance_sheet_W10_LH_1b3e3b4b_0_0': {'x': 0,
   'y': 0,
   'rotation': 0,
   'mirror': False},
  'resistance_sheet_W10_LH_1b3e3b4b_0_m50000': {'x': 0,
   'y': -50,
   'rotation': 180,
   'mirror': False},
  'resistance_sheet_W10_LH_1b3e3b4b_50000_0': {'x': 50,
   'y': 0,
   'rotation': 270,
   'mirror': False},
  'resistance_sheet_W10_LH_1b3e3b4b_m100000_m50000': {'x': -100,
   'y': -50,
   'rotation': 180,
   'mirror': False}},
 'ports': {},
 'name': 'Unnamed_85',
 'warnings': {'electrical': {'unconnected_ports': ({'ports': ('resistance_sheet_W10_LH_1b3e3b4b_m100000_m50000,pad2',
      'resistance_sheet_W10_LH_1b3e3b4b_50000_0,pad1',
      'resistance_sheet_W10_LH_1b3e3b4b_50000_0,pad2'),
     'values': ((-150000, -25000), (25000, 50000), (25000, -50000)),
     'message': '3 unconnected electrical ports!'},)}}}