march2022_level0 — PyG power-electronics graphs (Level-0 parent corpus)

Variable-length PyTorch Geometric Data graphs built from the March 2022 Level-0 raw dump (data/March2022 Raw/). Each row pairs a fixed netlist topology with one sweep design and pre-computed metric_data — no ngSpice, no .raw waveforms.

This is the parent corpus audited in notebooks/march2022/verify_march2022_dataset.ipynb. Downstream Level-2 datasets in this repo re-simulate one topology family with ngSpice and attach waveforms.

Build notebook: notebooks/march2022/build_march2022_pyg_dataset.ipynb

Hub: LiangXD/march2022_level0

Metric provenance

Only metric_success applies here (finite DcGain and finite Voltage_Ripple from metric_data). This matches Branch B of the repo’s simulation_success tree — without Branch A (waveforms) or ngSpice infrastructure legs.

Vector PDF · metric_success.md

Build summary (notebook §7)

Counts below follow the tree above (metric_success = 0 categories map to failure leaves).

split	graphs	build wall time
train	1,208,102	2h 27m 33s
val	345,171	40m 20s
test	172,587	20m 46s
overall	1,725,860	3h 29m 25s

metric_success tally

	count
metric_success = 1	1,021,987
metric_success = 0	703,873
check	1,725,860

metric_success = 0 categories

category	count
nan_gain	599,458
zero_gain_nan_ripple	99,645
positive_gain_nan_ripple	4,770

large_ripple = 1: 3,999 (per-split indices in graphs/large_ripple.json).

Build reference (Windows, Jul 2026)

item	value
Platform	Windows 10, Python 3.9.6, PyTorch 2.1.1, PyG 2.6.1
RAM	32 GB (+ pagefile 16–48 GB on C: during train.pt save)
Wall time	3h 29m (train 2h 28m · val 40m · test 21m)
On-disk size	~10.4 GB total (train 7.33 · val 2.05 · test 1.03 GB)
Raw parent dump	<2 GB tabular (sweep_table.csv + metric_data per folder)

Metrics-only graphs (no waveforms) — on-disk .pt size is much smaller than in-RAM peak (~31 GB during pickle) thanks to compact tensors and pickle memoization (e.g. shared color_map).

Verification (build notebook)

Stage	Check
7b (pre-upload)	Semantic: spot-check test.pt vs raw sweep_table.csv + metric_data
8b (post-upload)	Integrity: local test.pt SHA256 vs Hub graphs/test.pt SHA256

Corpus scale (index pass)

item	count
CircuitN folders	~4,607
distinct iso_topo_hash	~1,538
used sweep rows	~1,725,860

Used rows = min(n_sweep_rows, n_metric_rows) per folder (drops trailing zero-padding in metric_data).

Variable-length graphs

Unlike single-topology Level-2 datasets, num_nodes, initial_design, and switching_parameters lengths depend on the family field (S_D_L_C_N).

Canonical initial_design layout

Parse family as n_S, n_D, n_L, n_C, n_N (use the first four):

initial_design[0 : n_C]              → C0 … C{n_C-1} capacitances (F)
initial_design[n_C : n_C+n_L]        → L0 … L{n_L-1} inductances (H)
initial_design[n_C+n_L]              → shared T1 (from GS0_T1 in sweep_table; stored as-is)
initial_design[n_C+n_L+1 : +n_S]     → GS0_L1 … GS{n_S-1}_L1
initial_design[…+n_S : +n_S]         → GS0_L2 … GS{n_S-1}_L2

Length = n_C + n_L + 1 + 2×n_S.

T1 / duty units: GS#_T1 values are stored as-is from sweep_table.csv (no rescaling). They look like normalized duty ratios (~0–1), not absolute switch-on times in seconds. We have not verified whether the implied switching period matches Level-2’s 5 µs base (GS{i}_T1 = duty × 5e-6 s in rewritten netlists). That ambiguity does not affect comparability within this dataset: every March 2022 sample was generated under the same underlying sweep convention.

Empirical scan (first sweep row per folder, GS0_T1; all GS#_T1 identical per row in 4,607 / 4,607 folders):

Stat	Value
min / median / max (GS0_T1)	0.000178 / 0.503 / 0.990
folders with GS0_T1 ∈ [0.1, 0.9]	4,570
folders with GS0_T1 < 1e-4 (seconds-like)	0
folders with GS0_T1 outside [0.05, 1.0]	11

On each Data graph, the shared duty appears as initial_design[n_C+n_L], switching_parameters[0], and input_feature[S#][0] — not a separate T1_shared field.

node_name ↔ edge_index ↔ initial_design

node_name[i] is the string label for integer node i in edge_index. Component values align by designator suffix, not list position:

k = int("C0"[1:])  # → 0
c0_design = g.initial_design[k]
c0_feat   = g.input_feature[g.node_name.index("C0")][0]
# c0_design == c0_feat

switching_parameters has length 1 + 2×n_S: [T1_duty, GS0_L1…, GS0_L2…] (switching_parameters[0] = shared duty).

WL hashes (provenance)

field	definition
iso_topo_hash	networkx.weisfeiler_lehman_graph_hash on connectivity graph; switch nodes labeled S
sw_topo_hash	same, but switches relabeled S_{L1}{L2} from the sweep row before hashing

Same definitions as notebooks/march2022/verify_march2022_dataset.ipynb (state-augmented WL for switch assignment).

Fields on each Data

Present: edge_index, num_nodes, node_type, node_name, bipartite, input_feature, initial_design, switching_parameters, DcGain, Voltage_Ripple, metric_success, zero_dc_gain, large_ripple, split, sample_index, folder_key, family, group, iso_topo_hash, sw_topo_hash, color_map.

Absent (no ngSpice / no waveforms): V_sw, I_sw, V_r0_full, ngspice_run_success, waveform_success, simulation_success, sw_pre_n, sw_post_n, rewrite_netlist_str, raw_file.

Splits

Global shuffle (SHUFFLE_SEED=523), then 7:2:1 train/val/test (same ratio as dataset_configs/sampling.py).

split	graphs
train	1,208,102
val	345,171
test	172,587
total	1,725,860

Build wall times and full metric_success / large_ripple tallies: see Build summary under Metric provenance.

Repository layout (Hub)

graphs/
├── train.pt
├── val.pt
├── test.pt
└── large_ripple.json
level0_metric_success_tree.png
level0_metric_success_tree.pdf
metric_success.md
README.md

Load example

import torch

graphs = torch.load("artifacts/march2022_level0/graphs/train.pt", weights_only=False)
g = graphs[0]

print(g.family, g.folder_key, g.num_nodes)
print(int(g.metric_success), float(g.DcGain), float(g.Voltage_Ripple))
print(g.initial_design.shape, g.switching_parameters.shape)

# name → index
i = g.node_name.index("C0")
print(g.node_name[i], g.input_feature[i])

Training with PyG

Graphs are undirected; edge_index stores both orientations. Use data.edge_index as-is in PyG layers.

Because graphs vary in size, use a custom collate or batch size 1 unless you pad initial_design / node features explicitly.