d

src/derivatives.py

@@ -39,7 +39,7 @@ def filter_data(file: Path) -> pd.DataFrame:
     previous_crank = -1
     last_cam = -1
     cam_flag = 0
-    crank_flag = 0
+    crank_flag = False
 
     for _, row in tqdm(df.iterrows(), total=len(df), desc="Derivative"):
         time_us: int = row["time_us"]
@@ -48,11 +48,17 @@ def filter_data(file: Path) -> pd.DataFrame:
         c1 = 0
         c2 = 0
         if crank==1:
-            rows.append({
-                "time_us": time_us,
-                "d1": time_us-c1,
-                "d2": (time_us-2*c1+c2)/(c1-c2),
-            })
+            d1 = tume_us-c1
+            d2 = d1-(c1-c2)
+            if crank_flag:
+                rows.append({
+                    "time_us": time_us,
+                    "d1": d1,
+                    "d2": d2,
+                    "ratio": d2/d1
+                })
+            else:
+                crank_flag = True
             c2=c1
             c1=time_us
         output = pd.DataFrame(rows)