GPT-Image / code /evaluate.py
MaybeRichard's picture
Add training and evaluation code
3c366de verified
Raw
History Blame Contribute Delete
8.28 kB
#!/usr/bin/env python3
# -*- coding: utf-8 -*-
"""
Unified evaluation for ALL models (RETFound / ResNet / ViT).
Reads <run_dir>/test_pred.npz (y_true:(N,), y_prob:(N,C)) saved by every training
run, then computes the full classification metric suite and writes:
<run_dir>/metrics.json
<run_dir>/confusion_matrix.png (counts + row-normalized)
<run_dir>/roc.png (binary: 1 curve; multiclass: per-class OvR + macro/micro)
<run_dir>/pr.png (precision-recall, same layout)
Using one shared script guarantees identical metric definitions across the 3 models.
"""
import os, sys, json, argparse
import numpy as np
import matplotlib
matplotlib.use("Agg")
import matplotlib.pyplot as plt
from sklearn.metrics import (accuracy_score, balanced_accuracy_score, f1_score,
precision_score, recall_score, cohen_kappa_score,
matthews_corrcoef, roc_auc_score, average_precision_score,
roc_curve, precision_recall_curve, confusion_matrix,
classification_report)
def _safe(fn, *a, **k):
try:
return float(fn(*a, **k))
except Exception:
return None
def compute_metrics(y_true, y_prob):
y_true = np.asarray(y_true).astype(int)
y_prob = np.asarray(y_prob)
C = y_prob.shape[1]
y_pred = y_prob.argmax(1)
classes = list(range(C))
y_true_oh = np.eye(C)[y_true]
binary = (C == 2)
m = {"n_test": int(len(y_true)), "n_classes": C, "task": "binary" if binary else "multiclass"}
# ---- threshold-based (argmax) ----
m["accuracy"] = _safe(accuracy_score, y_true, y_pred)
m["balanced_accuracy"] = _safe(balanced_accuracy_score, y_true, y_pred)
m["precision_macro"] = _safe(precision_score, y_true, y_pred, average="macro", zero_division=0)
m["recall_macro"] = _safe(recall_score, y_true, y_pred, average="macro", zero_division=0)
m["f1_macro"] = _safe(f1_score, y_true, y_pred, average="macro", zero_division=0)
m["precision_weighted"] = _safe(precision_score, y_true, y_pred, average="weighted", zero_division=0)
m["recall_weighted"] = _safe(recall_score, y_true, y_pred, average="weighted", zero_division=0)
m["f1_weighted"] = _safe(f1_score, y_true, y_pred, average="weighted", zero_division=0)
m["cohen_kappa"] = _safe(cohen_kappa_score, y_true, y_pred)
m["quadratic_weighted_kappa"] = _safe(cohen_kappa_score, y_true, y_pred, weights="quadratic")
m["mcc"] = _safe(matthews_corrcoef, y_true, y_pred)
# ---- probability-based ----
if binary:
s = y_prob[:, 1]
m["auroc"] = _safe(roc_auc_score, y_true, s)
m["auprc"] = _safe(average_precision_score, y_true, s)
cm = confusion_matrix(y_true, y_pred, labels=classes)
tn, fp, fn, tp = cm.ravel()
m["sensitivity"] = float(tp / (tp + fn)) if (tp + fn) else None # recall of positive
m["specificity"] = float(tn / (tn + fp)) if (tn + fp) else None
m["precision_pos"] = float(tp / (tp + fp)) if (tp + fp) else None
m["f1_pos"] = _safe(f1_score, y_true, y_pred, pos_label=1, zero_division=0)
else:
m["auroc_macro_ovr"] = _safe(roc_auc_score, y_true_oh, y_prob, multi_class="ovr", average="macro")
m["auroc_weighted_ovr"] = _safe(roc_auc_score, y_true_oh, y_prob, multi_class="ovr", average="weighted")
m["auprc_macro"] = _safe(average_precision_score, y_true_oh, y_prob, average="macro")
per_auc = {}
for c in classes:
per_auc[str(c)] = _safe(roc_auc_score, (y_true == c).astype(int), y_prob[:, c])
m["auroc_per_class"] = per_auc
# per-class report (precision/recall/f1/support)
m["per_class"] = classification_report(y_true, y_pred, labels=classes,
output_dict=True, zero_division=0)
return m, y_true, y_pred, y_prob
def plot_confusion(y_true, y_pred, C, names, path):
cm = confusion_matrix(y_true, y_pred, labels=list(range(C)))
cmn = cm.astype(float) / cm.sum(1, keepdims=True).clip(min=1)
fig, axes = plt.subplots(1, 2, figsize=(6 * 2, 5))
for ax, mat, title, fmt in [(axes[0], cm, "Confusion (counts)", "d"),
(axes[1], cmn, "Confusion (row-normalized)", ".2f")]:
im = ax.imshow(mat, cmap="Blues", vmin=0, vmax=(cm.max() if fmt == "d" else 1))
ax.set_xticks(range(C)); ax.set_yticks(range(C))
ax.set_xticklabels(names, rotation=45, ha="right"); ax.set_yticklabels(names)
ax.set_xlabel("Predicted"); ax.set_ylabel("True"); ax.set_title(title)
for i in range(C):
for j in range(C):
v = mat[i, j]
ax.text(j, i, format(v, fmt), ha="center", va="center",
color="white" if v > (mat.max() * 0.6) else "black", fontsize=8)
fig.colorbar(im, ax=ax, fraction=0.046, pad=0.04)
fig.tight_layout(); fig.savefig(path, dpi=200, bbox_inches="tight"); plt.close(fig)
def plot_roc(y_true, y_prob, C, names, path):
fig, ax = plt.subplots(figsize=(6, 5))
if C == 2:
fpr, tpr, _ = roc_curve(y_true, y_prob[:, 1])
auc = roc_auc_score(y_true, y_prob[:, 1])
ax.plot(fpr, tpr, label=f"ROC (AUC={auc:.3f})")
else:
y_oh = np.eye(C)[y_true]
for c in range(C):
try:
fpr, tpr, _ = roc_curve(y_oh[:, c], y_prob[:, c])
auc = roc_auc_score(y_oh[:, c], y_prob[:, c])
ax.plot(fpr, tpr, label=f"{names[c]} (AUC={auc:.3f})", lw=1)
except Exception:
pass
try:
macro = roc_auc_score(y_oh, y_prob, multi_class="ovr", average="macro")
ax.plot([], [], " ", label=f"macro-AUC={macro:.3f}")
except Exception:
pass
ax.plot([0, 1], [0, 1], "k--", lw=0.8)
ax.set_xlabel("False Positive Rate"); ax.set_ylabel("True Positive Rate")
ax.set_title("ROC"); ax.legend(fontsize=8, loc="lower right")
fig.tight_layout(); fig.savefig(path, dpi=200, bbox_inches="tight"); plt.close(fig)
def plot_pr(y_true, y_prob, C, names, path):
fig, ax = plt.subplots(figsize=(6, 5))
if C == 2:
prec, rec, _ = precision_recall_curve(y_true, y_prob[:, 1])
ap = average_precision_score(y_true, y_prob[:, 1])
ax.plot(rec, prec, label=f"PR (AP={ap:.3f})")
else:
y_oh = np.eye(C)[y_true]
for c in range(C):
try:
prec, rec, _ = precision_recall_curve(y_oh[:, c], y_prob[:, c])
ap = average_precision_score(y_oh[:, c], y_prob[:, c])
ax.plot(rec, prec, label=f"{names[c]} (AP={ap:.3f})", lw=1)
except Exception:
pass
ax.set_xlabel("Recall"); ax.set_ylabel("Precision")
ax.set_title("Precision-Recall"); ax.legend(fontsize=8, loc="lower left")
fig.tight_layout(); fig.savefig(path, dpi=200, bbox_inches="tight"); plt.close(fig)
def main():
ap = argparse.ArgumentParser()
ap.add_argument("--run_dir", required=True)
ap.add_argument("--class_names", default="")
args = ap.parse_args()
npz = os.path.join(args.run_dir, "test_pred.npz")
if not os.path.isfile(npz):
print(f"[evaluate] missing {npz}", file=sys.stderr); sys.exit(1)
d = np.load(npz)
y_true, y_prob = d["y_true"], d["y_prob"]
C = y_prob.shape[1]
names = args.class_names.split(",") if args.class_names else [str(i) for i in range(C)]
if len(names) != C:
names = [str(i) for i in range(C)]
metrics, y_true, y_pred, y_prob = compute_metrics(y_true, y_prob)
with open(os.path.join(args.run_dir, "metrics.json"), "w") as f:
json.dump(metrics, f, indent=2)
plot_confusion(y_true, y_pred, C, names, os.path.join(args.run_dir, "confusion_matrix.png"))
plot_roc(y_true, y_prob, C, names, os.path.join(args.run_dir, "roc.png"))
plot_pr(y_true, y_prob, C, names, os.path.join(args.run_dir, "pr.png"))
key = "auroc" if C == 2 else "auroc_macro_ovr"
print(f"[evaluate] {args.run_dir} acc={metrics['accuracy']:.4f} "
f"{key}={metrics.get(key)} f1_macro={metrics['f1_macro']:.4f} "
f"qwk={metrics['quadratic_weighted_kappa']}")
if __name__ == "__main__":
main()