Update Current_K6517B_Simple_Backend_v10.py

df error fix

Author: prathameshnium

Keithley_6517B/Pyroelectricity/Backends/Current_K6517B_Simple_Backend_v10.py

@@ -1,11 +1,9 @@
 #-------------------------------------------------------------------------------
 # Name:        Keithley 6517B electrometer
-# Purpose:
-#
-# Author:     Prathamesh K Deshmukh
-#
+# Purpose:     Current Measurement Backend
+# Author:      Prathamesh K Deshmukh
 # Created:     03-03-2024
-# updates: V1.3
+# Updates:     V1.3 (Fixed DataFrame saving bug)
 #-------------------------------------------------------------------------------
 
 import time
@@ -14,57 +12,45 @@
 import pyvisa
 from pymeasure.instruments.keithley import Keithley6517B
 
-
-I=[]
-t=[]
-#rm = pyvisa.ResourceManager()
-#keithley = rm.open_resource("GPIB::1")
+I = []
+t = []
 
 try:
-
+    # Initialize Instrument
     keithley = Keithley6517B("GPIB0::27::INSTR")
     time.sleep(0.5)
 
-    #keithley.apply_current()  # Sets up to source current
-    #keithley.current_range = 10e-3  # Sets the source current range to 10 mA
-    #keithley.compliance_voltage = 10  # Sets the compliance voltage to 10 V
-    #keithley.enable_source()  # Enables the source output
+    # Setup Measurement
     keithley.measure_current()
     time.sleep(0.5)
 
-
-    #data_columns = ["Timestamp", "Current (A)"]
-    #data_df = pd.DataFrame(columns=data_columns)
+    print("Starting measurement... Press Ctrl+C to stop.")
     start_time = time.time()
 
     while True:
         elapsed_time = time.time() - start_time
-        #timestamp = time.strftime("%Y-%m-%d %H:%M:%S")
         current = keithley.current  # Read current in Amps
-        #data_df = data_df.append({"Timestamp": elapsed_time, "Current (A)": current}, ignore_index=True)
+        
+        # Store data in lists
         t.append(elapsed_time)
         I.append(current)
-        print("Time: " +str(elapsed_time)+"\t\t\t|\t\t\t Current: "+str(current)+" A")
-
+        
+        print("Time: " + str(elapsed_time) + "\t\t\t|\t\t\t Current: " + str(current) + " A")
         time.sleep(2)
-    print("Measurement stopped...")
-
-    data_df.to_csv("demo_data.dat", index=False)
-    print(f"Data saved to file : demo_data.dat")
-
-
-
-
-except Exception as e:
-    print(f"error with keithley : {e}")
 
 except KeyboardInterrupt:
-    time.sleep(0.5)
+    # Graceful Exit on Ctrl+C
+    print("\nMeasurement stopped by User.")
+    
+    # --- FIX IS HERE: Define data_df before using it ---
+    data_df = pd.DataFrame({"Timestamp": t, "Current (A)": I})
+    data_df.to_csv("demo_data.dat", index=False)
+    print(f"Data saved to file: demo_data.dat")
 
-    keithley.clear()
-    #keithley.reset()
+    # Shutdown Sequence
     time.sleep(0.5)
+    keithley.shutdown()  # Ramps current to 0 and disables output
+    print("Keithley closed.")
 
-    keithley.shutdown()  # Ramps the current to 0 mA and disables output
-    print("\n\nkeithley closed")
-    print("\n Measurement stopped by User ")
+except Exception as e:
+    print(f"Error with Keithley: {e}")