Update app.py

app.py

@@ -6,7 +6,7 @@ import io
 st.set_page_config(page_title="Excel → Management Insights", layout="wide")
 
 st.title("📊 Excel → Interactive Management Dashboard")
-st.caption("Rule: PASS if Grade ≥ C | FAIL if below C (C- / D / F)")
+st.caption("PASS if Grade ≥ C | FAIL if C- / D / F")
 
 # -----------------------------
 # Grade logic
@@ -15,7 +15,6 @@ def grade_pass_fail(g):
     if pd.isna(g):
         return "Unknown"
     g = str(g).strip().upper()
-
     if g.startswith(("D", "E", "F")):
         return "Fail"
     if g.startswith("C"):
@@ -46,28 +45,29 @@ def ensure_sno(df):
 
 
 # -----------------------------
-# Upload section (SAFE)
+# Upload section (CORRECT)
 # -----------------------------
 uploaded = st.file_uploader("Upload Excel (.xlsx)", type=["xlsx"])
 
+file_bytes = None  # ✅ ALWAYS defined
+
 if uploaded is None:
     st.info("Upload an Excel file to begin.")
     st.stop()
 
-load_clicked = st.button("✅ Load file")
+if st.button("✅ Load file"):
+    try:
+        file_bytes = uploaded.read()
+    except Exception as e:
+        st.error(f"Failed to read file: {e}")
+        st.stop()
 
-if not load_clicked:
+# ⛔ Stop if button not clicked or file not read
+if file_bytes is None:
     st.warning("Click **Load file** after uploading.")
     st.stop()
 
-# -------- DEFINE file_bytes ONCE --------
-try:
-    file_bytes = uploaded.read()
-except Exception as e:
-    st.error(f"Failed to read uploaded file: {e}")
-    st.stop()
-
-if file_bytes is None or file_bytes == b"":
+if file_bytes == b"":
     st.error("Uploaded file is empty.")
     st.stop()
 
@@ -104,22 +104,13 @@ df["PassFail"] = df["Grade"].apply(grade_pass_fail)
 df["Pass"] = df["PassFail"] == "Pass"
 df["Fail"] = df["PassFail"] == "Fail"
 
-# -----------------------------
-# Sidebar
-# -----------------------------
-view = st.sidebar.radio(
-    "Perspective",
-    ["Executive", "Risk", "Student", "Export"],
-    index=0
-)
-
 # -----------------------------
 # KPIs
 # -----------------------------
 c1, c2, c3, c4 = st.columns(4)
 c1.metric("Students", len(df))
-c2.metric("Pass", df["Pass"].sum())
-c3.metric("Fail", df["Fail"].sum())
+c2.metric("Pass", int(df["Pass"].sum()))
+c3.metric("Fail", int(df["Fail"].sum()))
 c4.metric("Pass Rate", f"{df['Pass'].mean()*100:.1f}%")
 
 st.divider()
@@ -127,6 +118,8 @@ st.divider()
 # -----------------------------
 # Views
 # -----------------------------
+view = st.sidebar.radio("View", ["Executive", "Risk", "Student", "Export"])
+
 if view == "Executive":
     g = df["Grade"].value_counts().reset_index()
     g.columns = ["Grade", "Count"]
@@ -146,4 +139,4 @@ elif view == "Student":
 
 else:
     csv = df.to_csv(index=False).encode("utf-8")
-    st.download_button("⬇️ Download CSV", csv, "analysis_for_powerbi.csv", "text/csv")
+    st.download_button("⬇️ Download CSV for Power BI", csv, "analysis_for_powerbi.csv", "text/csv")