FCFS with err handeling and docs

Author: coderatul

cpu_sheduling.py

@@ -1,7 +1,7 @@
 import copy
 import prettytable
-at_prcs_mapping = {} # arrivaltime : processess mapping
-bt_at_mapping = {} # burst time : arrival time mapping
+at_prcs_mapping = {} # arrivaltime : [processess]
+bt_at_mapping = {} # burst time : [processess]
 
 class CpuSheduling():
     def __init__(self, name:list = [], arrival_time:list = [], burst_time:list = [], time_quantum= None) -> None:
@@ -10,6 +10,18 @@ def __init__(self, name:list = [], arrival_time:list = [], burst_time:list = [],
         self.burst_time = burst_time
         self.time_quantum = time_quantum
 
+        # checking if every process has a arrival time and burst time
+        if len(self.process) != len(self.arrival_time):
+            raise ValueError("Number of process(s) don't match number of arrival time(s) or vice versa")
+        if len(self.process) != len(self.burst_time):
+            raise ValueError("Number of process(s) don't match number of burst time(s) or vice versa")
+        
+        # checking if arrival time and burst time are of integer or float type
+        if not all(isinstance(at, (int, float)) for at in self.arrival_time):
+            raise ValueError("arrival time can only have integer/float value(s)")
+        if not all(isinstance(bt, (int, float)) for bt in self.burst_time):
+            raise ValueError("burst time can only have integer/float value(s)")
+
         # displaying processess, arival time and burst time in a tabular format
         print(10*"-","given process data",10*"-")
         table = prettytable.PrettyTable()
@@ -19,7 +31,9 @@ def __init__(self, name:list = [], arrival_time:list = [], burst_time:list = [],
         print(table)
         print()
 
+    
     def unique_at(self)->list:
+        """ returns unique arrival time in ascending order"""
         unique_at = []
         for at in self.arrival_time:
             if at not in unique_at:
@@ -28,6 +42,7 @@ def unique_at(self)->list:
         return unique_at
 
     def at_mapping(self)-> dict:
+        """ returns mapping of arrival time and processess as a dictionary"""
         for index, at in enumerate(self.arrival_time):
             if at not in at_prcs_mapping:
                 at_prcs_mapping[at] = [self.process[index]]
@@ -36,6 +51,7 @@ def at_mapping(self)-> dict:
         return at_prcs_mapping
 
     def bt_mapping(self)->dict:
+        """ returns mapping of burst time and arrival time as a dictionary"""
         for index, at in enumerate(self.arrival_time):
             if at not in bt_at_mapping:
                 bt_at_mapping[at] = [self.burst_time[index]]
@@ -44,13 +60,15 @@ def bt_mapping(self)->dict:
         return bt_at_mapping
 
     def final_data(self,mapping:dict)->list:
+        """ returns a list of processess in the order of their arrival time or burst time"""
         listed_data = []
         for prcs in self.unique_at():
             listed_data.append(mapping[prcs])
         data = [process for sublist in listed_data for process in sublist]
         return data
 
-    def correction(self,arrival_time:list, ct:list)->list:
+    def check_halt(self,arrival_time:list, ct:list)->list:
+        """ returns index and value if any halt is present in the process order"""
         correction_index = 0
         correction_value = 0
 
@@ -64,9 +82,9 @@ def fcfs(self):
         """
         first come first serve short term shdeuling
         """
-        execution_order = self.final_data(self.at_mapping())
-        process_ord = copy.deepcopy(execution_order)
-        bt_ord = self.final_data(self.bt_mapping())
+        execution_order = self.final_data(self.at_mapping()) # process order
+        process_ord = copy.deepcopy(execution_order) # process order for printing if correction is required
+        bt_ord = self.final_data(self.bt_mapping()) # burst time in the order of arrival time
 
         # calculating completion time of each process 
         ct = []
@@ -77,12 +95,10 @@ def fcfs(self):
                 temp = j
             ct.append(temp)    
 
-        at = sorted(self.arrival_time)
-        print(at, ct)
-        
+        at = sorted(self.arrival_time) # sorted arrival time
+        crrction_val, crrction_index = self.check_halt(at, ct) # correction value and index
 
-        crrction_val, crrction_index = self.correction(at, ct)
-        print(crrction_val, crrction_index)
+        # inserting halt for correction
         if crrction_val == 0:
             pass
         else:
@@ -92,6 +108,7 @@ def fcfs(self):
             ct[crrction_index] += crrction_val
             crrction_index += 1
 
+        # printing process order
         print("fcfs order: ",end="")
         for process in process_ord:
             if process == process_ord[-1]:
@@ -142,7 +159,7 @@ def rr(self):
 
 if __name__ == "__main__":
     prcs =["P1","P2","P3","P4"] #process
-    at = [0,1,5,6] # arrival time
+    at = [0,1,5,12] # arrival time
     bt = [2,2,3,4] # burst time
     shedule = CpuSheduling(prcs,at,bt) 
     shedule.fcfs()