Files
Engine-Control-Algos/src/plot.py

382 lines
11 KiB
Python

# Copyright (C) 2026 Hector van der Aa <hector@h3cx.dev>
# Copyright (C) 2026 Association Exergie <association.exergie@gmail.com>
# SPDX-License-Identifier: GPL-3.0-or-later
from __future__ import annotations
import argparse
import sys
from bisect import bisect_left
from dataclasses import dataclass
from pathlib import Path
import matplotlib.pyplot as plt
import pandas as pd
from matplotlib.ticker import MultipleLocator
GP_COLUMNS = ("gp0_falling", "gp1_falling")
SPARK_COLUMNS = ("spark_1", "spark_2", "spark_3")
PULSE_STYLES = {
"gp0_falling": ("gp0 falling", "tab:green", 5.0, 0.18),
"gp1_falling": ("gp1 falling", "tab:red", 5.0, 0.18),
"spark_1": ("spark 1", "tab:blue", 2.4, 0.65),
"spark_2": ("spark 2", "tab:orange", 2.4, 0.65),
"spark_3": ("spark 3", "tab:purple", 2.4, 0.65),
}
@dataclass(frozen=True)
class EncoderPoint:
time_us: int
continuous_angle_deg: float
def read_csv(path: Path) -> pd.DataFrame:
df = pd.read_csv(path)
if "time_us" not in df.columns:
raise ValueError("missing column: time_us")
df["time_us"] = df["time_us"].astype("int64")
return df
def encoder_points(df: pd.DataFrame) -> list[EncoderPoint]:
required = {"time_us", "revolution_index", "crank_angle_deg"}
if not required <= set(df.columns):
return []
points: list[EncoderPoint] = []
angle_df = df.dropna(subset=["revolution_index", "crank_angle_deg"])
for row in angle_df.itertuples():
revolution_index = int(row.revolution_index)
if revolution_index < 0:
continue
continuous_angle = revolution_index * 360.0 + float(row.crank_angle_deg)
points.append(EncoderPoint(int(row.time_us), continuous_angle))
deduped: dict[int, EncoderPoint] = {}
for point in sorted(points, key=lambda item: item.time_us):
deduped[point.time_us] = point
return list(deduped.values())
def interpolate_angle(points: list[EncoderPoint], time_us: int) -> float | None:
if not points:
return None
times = [point.time_us for point in points]
index = bisect_left(times, time_us)
if index < len(points) and points[index].time_us == time_us:
return points[index].continuous_angle_deg
if index == 0 or index == len(points):
return None
before = points[index - 1]
after = points[index]
span = after.time_us - before.time_us
if span <= 0:
return before.continuous_angle_deg
fraction = (time_us - before.time_us) / span
return before.continuous_angle_deg + fraction * (
after.continuous_angle_deg - before.continuous_angle_deg
)
def iter_csv_paths(path: Path) -> list[Path]:
if path.is_dir():
return sorted(path.rglob("*.csv"))
return [path]
def has_angle_data(points: list[EncoderPoint]) -> bool:
return len(points) >= 2
def rpm_rows(df: pd.DataFrame) -> pd.DataFrame:
if "rpm_raw" not in df.columns or "rpm_lpf" not in df.columns:
return pd.DataFrame()
return df.dropna(subset=["rpm_raw", "rpm_lpf"])
def plot_time(df: pd.DataFrame, ax: plt.Axes) -> None:
rpm_df = rpm_rows(df)
if not rpm_df.empty:
time_s = rpm_df["time_us"] / 1_000_000.0
ax.plot(time_s, rpm_df["rpm_raw"], label="raw", linewidth=0.75, alpha=0.35)
ax.plot(time_s, rpm_df["rpm_lpf"], label="lpf", linewidth=1.4)
ax.set_xlabel("time (s)")
def plot_angle_overlay(df: pd.DataFrame, ax: plt.Axes) -> None:
rpm_df = rpm_rows(df)
if rpm_df.empty:
return
raw_label_used = False
lpf_label_used = False
for revolution in sorted(rpm_df["revolution_index"].dropna().astype(int).unique()):
if revolution < 0:
continue
rev_df = rpm_df[rpm_df["revolution_index"].astype(int) == revolution]
ax.plot(
rev_df["crank_angle_deg"],
rev_df["rpm_raw"],
color="0.55",
linewidth=0.5,
alpha=0.12,
label="raw" if not raw_label_used else None,
)
ax.plot(
rev_df["crank_angle_deg"],
rev_df["rpm_lpf"],
linewidth=0.8,
alpha=0.28,
label="lpf per rev" if not lpf_label_used else None,
)
raw_label_used = True
lpf_label_used = True
ax.set_xlim(0, 360)
ax.set_xlabel("crank angle (deg)")
def plot_angle_continuous(df: pd.DataFrame, ax: plt.Axes) -> None:
rpm_df = rpm_rows(df)
if rpm_df.empty:
return
angle_df = rpm_df.dropna(subset=["revolution_index", "crank_angle_deg"])
angle_df = angle_df[angle_df["revolution_index"].astype(int) >= 0]
if angle_df.empty:
return
continuous_angle = (
angle_df["revolution_index"].astype(float) * 360.0
+ angle_df["crank_angle_deg"].astype(float)
)
ax.plot(continuous_angle, angle_df["rpm_raw"], label="raw", linewidth=0.75, alpha=0.35)
ax.plot(continuous_angle, angle_df["rpm_lpf"], label="lpf", linewidth=1.4)
max_angle = float(continuous_angle.max())
turn_angle = 0.0
while turn_angle <= max_angle:
ax.axvline(turn_angle, color="0.7", linewidth=0.5, alpha=0.35)
turn_angle += 360.0
ax.set_xlim(0, max_angle)
ax.xaxis.set_major_locator(MultipleLocator(360.0))
ax.xaxis.set_minor_locator(MultipleLocator(180.0))
ax.set_xlabel("continuous crank angle (deg)")
def selected_pulse_columns(
df: pd.DataFrame,
gp_mode: str,
spark_columns: list[str],
) -> list[str]:
columns: list[str] = []
if gp_mode in {"gp0", "both"} and "gp0_falling" in df.columns:
columns.append("gp0_falling")
if gp_mode in {"gp1", "both"} and "gp1_falling" in df.columns:
columns.append("gp1_falling")
columns.extend(column for column in spark_columns if column in df.columns)
return columns
def pulse_x_value(
row: pd.Series,
*,
x_axis: str,
points: list[EncoderPoint],
) -> float | None:
time_us = int(row["time_us"])
if x_axis == "time":
return time_us / 1_000_000.0
continuous_angle = interpolate_angle(points, time_us)
if continuous_angle is None:
return None
if x_axis in {"angle", "angle-overlay"}:
return continuous_angle % 360.0
return continuous_angle
def plot_pulse_bars(
df: pd.DataFrame,
ax: plt.Axes,
*,
x_axis: str,
gp_mode: str,
spark_columns: list[str],
points: list[EncoderPoint],
) -> None:
for column in selected_pulse_columns(df, gp_mode, spark_columns):
label, color, linewidth, alpha = PULSE_STYLES[column]
pulse_df = df.loc[df[column].fillna(0).astype(int) == 1]
plotted_label = False
for _, row in pulse_df.iterrows():
x_value = pulse_x_value(row, x_axis=x_axis, points=points)
if x_value is None:
continue
ax.axvline(
x_value,
color=color,
alpha=alpha,
linewidth=linewidth,
label=label if not plotted_label else None,
)
plotted_label = True
def plot_file(
csv_path: Path,
output: Path | None,
*,
x_axis: str,
gp_mode: str,
spark_columns: list[str],
) -> bool:
try:
df = read_csv(csv_path)
except (OSError, ValueError) as exc:
print(f"Could not read {csv_path}: {exc}", file=sys.stderr)
return False
points = encoder_points(df)
if x_axis.startswith("angle") and not has_angle_data(points):
print(f"Could not plot crank angle for {csv_path}: missing angle columns", file=sys.stderr)
return False
fig, ax = plt.subplots(figsize=(12, 5))
if x_axis in {"angle", "angle-overlay"}:
plot_angle_overlay(df, ax)
elif x_axis == "angle-continuous":
plot_angle_continuous(df, ax)
else:
plot_time(df, ax)
plot_pulse_bars(
df,
ax,
x_axis=x_axis,
gp_mode=gp_mode,
spark_columns=spark_columns,
points=points,
)
ax.set_ylabel("RPM")
ax.set_title(str(csv_path))
ax.grid(alpha=0.25)
if x_axis == "angle-continuous":
ax.grid(which="minor", axis="x", alpha=0.15, linewidth=0.6)
ax.legend()
fig.tight_layout()
if output is not None:
output.parent.mkdir(parents=True, exist_ok=True)
fig.savefig(output, dpi=160)
print(f"Wrote {output}")
plt.close(fig)
else:
plt.show()
plt.close(fig)
return True
def output_path_for(csv_path: Path, output: Path | None, multiple: bool) -> Path | None:
if output is None:
return None
if not multiple:
return output
return output / f"{csv_path.stem}.png"
def parse_spark_columns(value: str) -> list[str]:
if value == "none":
return []
if value == "all":
return list(SPARK_COLUMNS)
columns = [column.strip() for column in value.split(",") if column.strip()]
if not columns:
raise argparse.ArgumentTypeError("must specify at least one spark column")
invalid = sorted(set(columns) - set(SPARK_COLUMNS))
if invalid:
valid = ", ".join(("none", "all", *SPARK_COLUMNS))
raise argparse.ArgumentTypeError(
f"invalid spark column(s): {', '.join(invalid)}; choose from {valid}"
)
deduped: list[str] = []
for column in columns:
if column not in deduped:
deduped.append(column)
return deduped
def parse_args() -> argparse.Namespace:
parser = argparse.ArgumentParser(description="Plot algo1 RPM output CSV files.")
parser.add_argument("csv_path", type=Path, help="Algo1 CSV file or directory of CSV files.")
parser.add_argument("-o", "--output", type=Path, help="Optional image output path or directory.")
parser.add_argument(
"--x",
choices=("time", "angle", "angle-overlay", "angle-continuous"),
default="time",
help="Plot RPM against time, overlaid 0-360 crank angle, or continuous crank angle.",
)
parser.add_argument(
"--gp",
choices=("none", "gp0", "gp1", "both"),
default="both",
help="Overlay GP falling events as vertical bars.",
)
parser.add_argument(
"--sparks",
type=parse_spark_columns,
default="all",
help="Overlay spark events: none, all, one spark, or a comma-separated subset.",
)
return parser.parse_args()
def main() -> int:
args = parse_args()
if not args.csv_path.exists():
print(f"Path does not exist: {args.csv_path}", file=sys.stderr)
return 1
csv_paths = iter_csv_paths(args.csv_path)
if not csv_paths:
print(f"No CSV files found under {args.csv_path}", file=sys.stderr)
return 1
multiple = len(csv_paths) > 1
if multiple and args.output is not None and args.output.suffix:
print("When plotting a directory, --output must be a directory.", file=sys.stderr)
return 1
spark_columns = (
args.sparks if isinstance(args.sparks, list) else parse_spark_columns(args.sparks)
)
failures = 0
for csv_path in csv_paths:
output = output_path_for(csv_path, args.output, multiple)
if not plot_file(
csv_path,
output,
x_axis=args.x,
gp_mode=args.gp,
spark_columns=spark_columns,
):
failures += 1
return 1 if failures else 0
if __name__ == "__main__":
sys.exit(main())