Update app.py

app.py

@@ -1,7 +1,7 @@
 import gradio as gr
 import math
 
-def calculate_coffee_temp(cooling_time_min, initial_temperature_C, ambient_temperature_C, volume_coffee_ml, diameter_mug_mm):
+def calculate_cooling_time(initial_temperature_C, ambient_temperature_C, volume_coffee_ml, diameter_mug_mm, desired_temperature_C):
     # Constants
     specific_heat_water_J_per_g_C = 4.186  # in J/g°C
     thermal_conductivity_ceramic_W_per_m_K = 1  # in W/m·K
@@ -30,24 +30,28 @@ def calculate_coffee_temp(cooling_time_min, initial_temperature_C, ambient_tempe
     # Estimate the cooling constant
     cooling_constant = (thermal_conductivity_ceramic_W_per_m_K * surface_area_coffee_m2 * delta_temperature_C) / (specific_heat_water_J_per_g_C * mass_coffee_g)
 
-    # Convert time to seconds
-    cooling_time_s = cooling_time_min * 60  # convert minutes to seconds
+    # Check if the desired temperature is less than the initial temperature
+    if desired_temperature_C >= initial_temperature_C:
+        return "Desired temperature must be less than initial temperature"
 
-    # Calculate the temperature of the coffee after the specified time
-    temperature_C = ambient_temperature_C + (initial_temperature_C - ambient_temperature_C) * math.exp(-cooling_constant * cooling_time_s)
+    # Rearrange the temperature equation to solve for time
+    cooling_time_s = -math.log((desired_temperature_C - ambient_temperature_C) / (initial_temperature_C - ambient_temperature_C)) / cooling_constant
 
-    return temperature_C
+    # Convert the cooling time from seconds to minutes
+    cooling_time_min = cooling_time_s / 60
+
+    return cooling_time_min
 
 iface = gr.Interface(
-    fn=calculate_coffee_temp, 
+    fn=calculate_cooling_time, 
     inputs=[
-        gr.inputs.Number(label="Cooling time (minutes)"),
         gr.inputs.Number(label="Initial temperature of coffee (C)"),
         gr.inputs.Number(label="Ambient temperature (C)"),
         gr.inputs.Number(label="Volume of coffee (ml)"),
-        gr.inputs.Number(label="Diameter of mug (mm)")
+        gr.inputs.Number(label="Diameter of mug (mm)"),
+        gr.inputs.Number(label="Desired temperature (C)")
     ], 
-    outputs=gr.outputs.Textbox(label="Estimated coffee temperature (C)"),
+    outputs=gr.outputs.Textbox(label="Estimated cooling time (minutes)"),
 )
 
 iface.launch()