Create app.py

app.py

@@ -0,0 +1,56 @@
+import gradio as gr
+
+def calculate_tvm(initial_investment, annual_revenue, annual_opex, tax_rate, years, discount_rate):
+    # Convert percentages to decimals
+    i = discount_rate / 100
+    t_rate = tax_rate / 100
+    
+    annual_cash_flow = (annual_revenue - annual_opex) * (1 - t_rate)
+    
+    # Calculate NPV
+    npv = -initial_investment
+    for t in range(1, int(years) + 1):
+        npv += annual_cash_flow / ((1 + i) ** t)
+    
+    # Calculate Simple Payback Period
+    if annual_cash_flow > 0:
+        payback = initial_investment / annual_cash_flow
+    else:
+        payback = float('inf')
+        
+    return (
+        f"Resulting NPV: ${round(npv, 2):,}",
+        f"Annual After-Tax Cash Flow: ${round(annual_cash_flow, 2):,}",
+        f"Simple Payback Period: {round(payback, 2)} years"
+    )
+
+# Define the Interface
+with gr.Blocks(theme=gr.themes.Soft()) as demo:
+    gr.Markdown("# 🧪 Chemical Engineering TVM Calculator")
+    gr.Markdown("Evaluate the economic viability of process equipment or plant expansions.")
+    
+    with gr.Row():
+        with gr.Column():
+            inv = gr.Number(label="Initial Investment ($)", value=1000000)
+            rev = gr.Number(label="Annual Revenue ($)", value=500000)
+            opex = gr.Number(label="Annual OPEX ($)", value=150000)
+        with gr.Column():
+            tax = gr.Slider(0, 50, value=21, label="Tax Rate (%)")
+            years = gr.Slider(1, 30, value=10, step=1, label="Project Life (Years)")
+            disc = gr.Slider(0, 20, value=10, label="Discount Rate / MARR (%)")
+            
+    btn = gr.Button("Calculate Economic Viability", variant="primary")
+    
+    with gr.Row():
+        out_npv = gr.Textbox(label="Net Present Value (NPV)")
+        out_cash = gr.Textbox(label="Annual Cash Flow")
+        out_payback = gr.Textbox(label="Payback Period")
+
+    btn.click(
+        fn=calculate_tvm, 
+        inputs=[inv, rev, opex, tax, years, disc], 
+        outputs=[out_npv, out_cash, out_payback]
+    )
+
+if __name__ == "__main__":
+    demo.launch()