diff --git a/gplugins/klayout/netlist_spice_reader.py b/gplugins/klayout/netlist_spice_reader.py
index 6d5c27de..4f982e19 100644
--- a/gplugins/klayout/netlist_spice_reader.py
+++ b/gplugins/klayout/netlist_spice_reader.py
@@ -58,13 +58,12 @@ def parse_element(self, s: str, element: str) -> kdb.ParseElementData:
                 x_value, y_value = (int(e) / 1000 for e in location_matches.group(1, 2))
 
             # Use default KLayout parser for rest of the SPICE
-            s, *_ = s.split("$")
+            s, *_ = s.split(" $")
 
         parsed = super().parse_element(s, element)
         parsed.parameters |= {"x": x_value, "y": y_value}
 
         # ensure uniqueness
-        parsed.model_name = parsed.model_name
         self.n_nodes += 1
         return parsed
 
@@ -72,6 +71,12 @@ def parse_element(self, s: str, element: str) -> kdb.ParseElementData:
     def hash_str_to_int(s: str) -> int:
         return int(hashlib.shake_128(s.encode()).hexdigest(4), 16)
 
+    def write_str_property_as_int(self, value: str) -> int:
+        """Store string property in hash map and return integer hash value."""
+        hashed_value = CalibreSpiceReader.hash_str_to_int(value)
+        self.integer_to_string_map[hashed_value] = value
+        return hashed_value
+
     @override
     def element(
         self,
@@ -95,15 +100,8 @@ def element(
         if not clx:
             clx = kdb.DeviceClass()
             clx.name = model
-            for key, value in parameters.items():
+            for key in parameters:
                 clx.add_parameter(kdb.DeviceParameterDefinition(key))
-                # map string variables to integers
-                if (
-                    isinstance(value, str)
-                    and value not in self.integer_to_string_map.values()
-                ):
-                    hashed_value = CalibreSpiceReader.hash_str_to_int(value)
-                    self.integer_to_string_map[hashed_value] = value
 
             for i in range(len(nets)):
                 clx.add_terminal(kdb.DeviceTerminalDefinition(str(i)))
@@ -114,12 +112,17 @@ def element(
             device.connect_terminal(i, net)
 
         for key, value in parameters.items():
+            # map string variables to integers
+            possibly_hashed_value = (
+                self.write_str_property_as_int(value)
+                if isinstance(value, str)
+                else value
+            )
+
             device.set_parameter(
                 key,
                 (
-                    CalibreSpiceReader.hash_str_to_int(value)
-                    if isinstance(value, str)
-                    else value
+                    possibly_hashed_value
                     or 0  # default to 0 for None in order to still have the parameter field
                 ),
             )
diff --git a/gplugins/klayout/plot_nets.py b/gplugins/klayout/plot_nets.py
index 12d9e742..ef622bfd 100644
--- a/gplugins/klayout/plot_nets.py
+++ b/gplugins/klayout/plot_nets.py
@@ -33,7 +33,12 @@ def plot_nets(
         spice_reader: The KLayout Spice reader to use for parsing SPICE netlists.
     """
 
-    G_connectivity = networkx_from_spice(**locals())
+    G_connectivity = networkx_from_spice(
+        filepath=filepath,
+        include_labels=include_labels,
+        top_cell=top_cell,
+        spice_reader=spice_reader,
+    )
 
     if nodes_to_reduce:
 
diff --git a/gplugins/path_length_analysis/path_length_analysis.py b/gplugins/path_length_analysis/path_length_analysis.py
index 0566372e..9dfcc447 100644
--- a/gplugins/path_length_analysis/path_length_analysis.py
+++ b/gplugins/path_length_analysis/path_length_analysis.py
@@ -24,6 +24,7 @@
 from bokeh.palettes import Category10, Spectral4
 from bokeh.plotting import figure, from_networkx
 from gdsfactory.component import Component, ComponentReference
+from gdsfactory.get_netlist import get_netlist, get_netlist_recursive
 
 DEFAULT_CS_COLORS = {
     "xs_rc": "red",
@@ -95,6 +96,7 @@ def report_pathlengths(
     result_dir: str | Path,
     visualize: bool = False,
     component_connectivity=None,
+    netlist=None,
 ) -> None:
     """Reports pathlengths for a given PIC.
 
@@ -103,11 +105,15 @@ def report_pathlengths(
         result_dir: the directory to write the pathlength table to.
         visualize: whether to visualize the pathlength graph.
         component_connectivity: a dictionary of component connectivity information.
+        netlist: a netlist dictionary. If None, will be generated from the pic.
     """
 
     print(f"Reporting pathlengths for {pic.name}...")
     pathlength_graph = get_edge_based_route_attr_graph(
-        pic, recursive=True, component_connectivity=component_connectivity
+        pic,
+        recursive=True,
+        component_connectivity=component_connectivity,
+        netlist=netlist,
     )
     route_records = get_paths(pathlength_graph)
 
@@ -332,7 +338,10 @@ def _get_edge_based_route_attr_graph(
 
 
 def get_edge_based_route_attr_graph(
-    pic: Component, recursive=False, component_connectivity=None
+    pic: Component,
+    recursive=False,
+    component_connectivity=None,
+    netlist: dict[str, Any] | None = None,
 ) -> nx.Graph:
     """
     Gets a connectivity graph for the circuit, with all path attributes on edges and ports as nodes.
@@ -342,17 +351,19 @@ def get_edge_based_route_attr_graph(
         recursive: True to expand all hierarchy. False to only report top-level connectivity.
         component_connectivity: a function to report connectivity for base components.\
                 None to treat as black boxes with no internal connectivity.
+        netlist: a netlist dictionary. If None, will be generated from the pic.
 
     Returns:
         A NetworkX Graph
     """
-    from gdsfactory.get_netlist import get_netlist, get_netlist_recursive
-
-    if recursive:
-        netlists = get_netlist_recursive(pic, component_suffix="")
-        netlist = netlists[pic.name]
+    if netlist is None:
+        if recursive:
+            netlists = get_netlist_recursive(pic, component_suffix="")
+            netlist = netlists[pic.name]
+        else:
+            netlist = get_netlist(pic)
+            netlists = None
     else:
-        netlist = get_netlist(pic)
         netlists = None
 
     return _get_edge_based_route_attr_graph(
diff --git a/gplugins/path_length_analysis/path_length_analysis_from_gds.py b/gplugins/path_length_analysis/path_length_analysis_from_gds.py
new file mode 100644
index 00000000..a89af573
--- /dev/null
+++ b/gplugins/path_length_analysis/path_length_analysis_from_gds.py
@@ -0,0 +1,164 @@
+from collections.abc import Callable
+from functools import partial
+
+import gdsfactory as gf
+import matplotlib.pyplot as plt
+import numpy as np
+from scipy.signal import savgol_filter
+
+filter_savgol_filter = partial(savgol_filter, window_length=11, polyorder=3, axis=0)
+
+
+def extract_path(
+    component: gf.Component,
+    layer: gf.typings.LayerSpec = (1, 0),
+    plot: bool = False,
+    filter_function: Callable = None,
+    under_sampling: int = 1,
+) -> gf.Path:
+    """Extracts the centerline of a component from a GDS file.
+
+    Args:
+        component: GDS component.
+        layer: GDS layer to extract the centerline from.
+        plot: Plot the centerline.
+        filter_function: optional Function to filter the centerline.
+        under_sampling: under sampling factor.
+    """
+    points = component.get_polygons(by_spec=layer)[0]
+
+    # Assume the points are ordered and the first half is the outer curve, the second half is the inner curve
+    # This assumption might need to be adjusted based on your specific geometry
+    mid_index = len(points) // 2
+    outer_points = points[:mid_index]
+    inner_points = points[mid_index:]
+    inner_points = inner_points[::-1]
+
+    inner_points = inner_points[::under_sampling]
+    outer_points = outer_points[::under_sampling]
+
+    centerline = np.mean([outer_points, inner_points], axis=0)
+
+    if filter_function is not None:
+        centerline = filter_function(centerline)
+
+    p = gf.Path(centerline)
+    if plot:
+        plt.figure()
+        plt.plot(outer_points[:, 0], outer_points[:, 1], "o", label="Outer Points")
+        plt.plot(inner_points[:, 0], inner_points[:, 1], "o", label="Inner Points")
+        plt.plot(centerline[:, 0], centerline[:, 1], "k--", label="Centerline")
+        plt.legend()
+        plt.title("Curve with Spline Interpolation for Inner and Outer Edges")
+        plt.xlabel("X-coordinate")
+        plt.ylabel("Y-coordinate")
+        plt.grid(True)
+        plt.show()
+    return p
+
+
+def get_min_radius_and_length(path: gf.Path) -> tuple[float, float]:
+    """Get the minimum radius of curvature and the length of a path."""
+    _, K = path.curvature()
+    radius = 1 / K
+    min_radius = np.min(np.abs(radius))
+    return min_radius, path.length()
+
+
+def plot_curvature(path: gf.Path, rmax: int | float = 200) -> None:
+    """Plot the curvature of a path.
+
+    Args:
+        path: Path object.
+        rmax: Maximum radius of curvature to plot.
+    """
+    s, K = path.curvature()
+    radius = 1 / K
+    valid_indices = (radius > -rmax) & (radius < rmax)
+    radius2 = radius[valid_indices]
+    s2 = s[valid_indices]
+
+    plt.figure(figsize=(10, 5))
+    plt.plot(s2, radius2, ".-")
+    plt.xlabel("Position along curve (arc length)")
+    plt.ylabel("Radius of curvature")
+    plt.show()
+
+
+def plot_radius(path: gf.Path, rmax: float = 200) -> plt.Figure:
+    """Plot the radius of curvature of a path.
+
+    Args:
+        path: Path object.
+        rmax: Maximum radius of curvature to plot.
+    """
+    s, K = path.curvature()
+    radius = 1 / K
+    valid_indices = (radius > -rmax) & (radius < rmax)
+    radius2 = radius[valid_indices]
+    s2 = s[valid_indices]
+
+    fig, ax = plt.subplots(1, 1, figsize=(15, 5))
+    ax.plot(s2, radius2, ".-")
+    ax.set_xlabel("Position along curve (arc length)")
+    ax.set_ylabel("Radius of curvature")
+    ax.grid(True)
+    return fig
+
+
+def _demo_routes():
+    ys_right = [0, 10, 20, 40, 50, 80]
+    pitch = 127.0
+    N = len(ys_right)
+    ys_left = [(i - N / 2) * pitch for i in range(N)]
+    layer = (1, 0)
+
+    right_ports = [
+        gf.Port(
+            f"R_{i}", center=(0, ys_right[i]), width=0.5, orientation=180, layer=layer
+        )
+        for i in range(N)
+    ]
+    left_ports = [
+        gf.Port(
+            f"L_{i}", center=(-200, ys_left[i]), width=0.5, orientation=0, layer=layer
+        )
+        for i in range(N)
+    ]
+
+    # you can also mess up the port order and it will sort them by default
+    left_ports.reverse()
+
+    c = gf.Component(name="connect_bundle_v2")
+    routes = gf.routing.get_bundle(
+        left_ports,
+        right_ports,
+        sort_ports=True,
+        start_straight_length=100,
+        enforce_port_ordering=False,
+    )
+    for route in routes:
+        c.add(route.references)
+    return c
+
+
+if __name__ == "__main__":
+    # c0 = gf.components.bend_euler(npoints=20)
+    # c0 = gf.components.bend_euler(cross_section="xs_sc", with_arc_floorplan=True)
+    # c0 = gf.components.bend_circular()
+    # c0 = gf.components.bend_s(npoints=7)
+    # c0 = gf.components.coupler()
+    c0 = _demo_routes()
+
+    gdspath = c0.write_gds()
+    n = c0.get_netlist()
+    c0.show()
+
+    c = gf.import_gds(gdspath)
+    # p = extract_path(c, plot=False, window_length=None, polyorder=None)
+    p = extract_path(c, plot=True, under_sampling=5)
+    min_radius, length = get_min_radius_and_length(p)
+    print(f"Minimum radius of curvature: {min_radius:.2f}")
+    print(f"Length: {length:.2f}")
+    print(c0.info)
+    plot_radius(p)
diff --git a/notebooks/11_get_netlist_spice.ipynb b/notebooks/11_get_netlist_spice.ipynb
index 39eef549..3f9f82a2 100644
--- a/notebooks/11_get_netlist_spice.ipynb
+++ b/notebooks/11_get_netlist_spice.ipynb
@@ -23,7 +23,9 @@
     "\n",
     "from gplugins.klayout.get_netlist import get_l2n, get_netlist\n",
     "from gplugins.klayout.plot_nets import plot_nets\n",
-    "from gplugins.klayout.netlist_graph import GdsfactorySpiceReader"
+    "from gplugins.klayout.netlist_spice_reader import (\n",
+    "    GdsfactorySpiceReader,\n",
+    ")\n"
    ]
   },
   {
@@ -45,6 +47,7 @@
    "source": [
     "c = pads_correct()\n",
     "gdspath = c.write_gds()\n",
+    "c.show()\n",
     "c.plot()"
    ]
   },
diff --git a/notebooks/path_length_analysis.ipynb b/notebooks/path_length_analysis.ipynb
index 77f86ebe..641de323 100644
--- a/notebooks/path_length_analysis.ipynb
+++ b/notebooks/path_length_analysis.ipynb
@@ -103,6 +103,108 @@
    "cell_type": "markdown",
    "id": "6",
    "metadata": {},
+   "source": [
+    "## Extract pathlength and curvature from component\n"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "7",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "import gplugins.path_length_analysis.path_length_analysis_from_gds as pl\n",
+    "import gdsfactory as gf"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "8",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "c0 = gf.components.bend_circular()\n",
+    "c0.plot()\n",
+    "gdspath = c0.write_gds()\n",
+    "n = c0.get_netlist()\n",
+    "\n",
+    "p = pl.extract_path(c0, plot=True)\n",
+    "min_radius, length = pl.get_min_radius_and_length(p)\n",
+    "print(f\"Minimum radius of curvature: {min_radius:.2f}\")\n",
+    "print(f\"Length: {length:.2f}\")\n",
+    "print(c0.info)\n",
+    "pl.plot_radius(p)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "id": "9",
+   "metadata": {},
+   "source": [
+    "## Extract pathlength and curvature from GDS\n",
+    "\n",
+    "To extract from GDS you need to save the netlist."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "10",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "c0 = gf.components.bend_circular()\n",
+    "c0.plot()\n",
+    "gdspath = c0.write_gds()\n",
+    "n = c0.get_netlist()\n",
+    "c = gf.import_gds(gdspath) # import the GDS file\n",
+    "\n",
+    "p = pl.extract_path(c, plot=True)\n",
+    "min_radius, length = pl.get_min_radius_and_length(p)\n",
+    "print(f\"Minimum radius of curvature: {min_radius:.2f}\")\n",
+    "print(f\"Length: {length:.2f}\")\n",
+    "print(c0.info)\n",
+    "pl.plot_radius(p)"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "11",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "p = pl.extract_path(c, plot=False, under_sampling=2)\n",
+    "min_radius, length = pl.get_min_radius_and_length(p)\n",
+    "print(f\"Minimum radius of curvature: {min_radius:.2f}\")\n",
+    "print(f\"Length: {length:.2f}\")\n",
+    "print(c0.info)\n",
+    "pl.plot_radius(p)"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "12",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "p = pl.extract_path(c, plot=False, under_sampling=5)\n",
+    "min_radius, length = pl.get_min_radius_and_length(p)\n",
+    "print(f\"Minimum radius of curvature: {min_radius:.2f}\")\n",
+    "print(f\"Length: {length:.2f}\")\n",
+    "print(c0.info)\n",
+    "pl.plot_radius(p)"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "13",
+   "metadata": {},
+   "outputs": [],
    "source": []
   }
  ],