Merge pull request #2950 from NitkarshChourasia/master

1 File Handle

Author: geekcomputers

1 File handle/File handle binary/.env

@@ -0,0 +1 @@
+STUDENTS_RECORD_FILE= "student_records.pkl"

1 File handle/File handle binary/Deleting record in a binary file.py

@@ -27,3 +27,7 @@ def update():
 
 
 update()
+
+# ! Instead of AB use WB?
+# ! It may have memory limits while updating large files but it would be good
+# ! Few lakhs records would be fine and wouln't create any much of a significant issues

1 File handle/File handle binary/Update a binary file2.py

@@ -0,0 +1,44 @@
+import logging
+import os
+import pickle
+
+from dotenv import load_dotenv
+
+base = os.path.dirname(__file__)
+load_dotenv(os.path.join(base, ".env"))
+
+logging.basicConfig(level=logging.INFO, format="%(levelname)s: %(message)s")
+student_record = os.getenv("STUDENTS_RECORD_FILE")
+
+
+def b_read():
+    # Opening a file & loading it
+    if not os.path.exists(student_record):
+        logging.warning("File not found")
+        return
+
+    with open(student_record, "rb") as F:
+        student = pickle.load(F)
+        logging.info("File opened successfully")
+        logging.info("Records in the file are:")
+        for i in student:
+            logging.info(i)
+
+
+def b_modify():
+    # Deleting the Roll no. entered by user
+    if not os.path.exists(student_record):
+        logging.warning("File not found")
+        return
+    roll_no = int(input("Enter the Roll No. to be deleted: "))
+    student = 0
+    with open(student_record, "rb") as F:
+        student = pickle.load(F)
+
+    with open(student_record, "wb") as F:
+        rec = [i for i in student if i[0] != roll_no]
+        pickle.dump(rec, F)
+
+
+b_read()
+b_modify()

1 File handle/File handle binary/delete.py

@@ -1,68 +1,66 @@
 """Amit is a monitor of class XII-A and he stored the record of all
-the students of his class in a file named “class.dat”.
+the students of his class in a file named “student_records.pkl”.
 Structure of record is [roll number, name, percentage]. His computer
 teacher has assigned the following duty to Amit
 
 Write a function remcount( ) to count the number of students who need
  remedial class (student who scored less than 40 percent)
+and find the top students of the class.
 
-
+We have to find weak students and bright students.
 """
-# also find no. of children who got top marks
+
+## Find bright students and weak students
+
+from dotenv import load_dotenv
+import os
+
+base = os.path.dirname(__file__)
+load_dotenv(os.path.join(base, ".env"))
+student_record = os.getenv("STUDENTS_RECORD_FILE")
 
 import pickle
+import logging
+
+# Define logger with info
+# import polar
 
-list = [
-    [1, "Ramya", 30],
-    [2, "vaishnavi", 60],
-    [3, "anuya", 40],
-    [4, "kamala", 30],
-    [5, "anuraag", 10],
-    [6, "Reshi", 77],
-    [7, "Biancaa.R", 100],
-    [8, "sandhya", 65],
-]
 
-with open("class.dat", "ab") as F:
-    pickle.dump(list, F)
-    F.close()
+## ! Unoptimised rehne de abhi ke liye
 
 
 def remcount():
-    with open("class.dat", "rb") as F:
+    with open(student_record, "rb") as F:
         val = pickle.load(F)
         count = 0
+        weak_students = []
 
-        for i in val:
-            if i[2] <= 40:
-                print(f"{i} eligible for remedial")
+        for student in val:
+            if student[2] <= 40:
+                print(f"{student} eligible for remedial")
+                weak_students.append(student)
                 count += 1
-        print(f"the total number of students are {count}")
+        print(f"the total number of weak students are {count}")
+        print(f"The weak students are {weak_students}")
 
-
-remcount()
+        # ! highest marks is the key here first marks
 
 
 def firstmark():
-    with open("class.dat", "rb") as F:
+    with open(student_record, "rb") as F:
         val = pickle.load(F)
         count = 0
         main = [i[2] for i in val]
 
         top = max(main)
         print(top, "is the first mark")
 
-        F.seek(0)
         for i in val:
             if top == i[2]:
                 print(f"{i}\ncongrats")
                 count += 1
-
-        print("the total number of students who secured top marks are", count)
+        print("The total number of students who secured top marks are", count)
 
 
+remcount()
 firstmark()
-
-with open("class.dat", "rb") as F:
-    val = pickle.load(F)
-    print(val)

1 File handle/File handle binary/question 1 (elegible for remedial, top marks).py

@@ -1,22 +1,22 @@
-import pickle
-
-
-def binary_read():
-    with open("studrec.dat", "rb") as b:
-        stud = pickle.load(b)
-        print(stud)
-
-        # prints the whole record in nested list format
-        print("contents of binary file")
-
-        for ch in stud:
-            print(ch)  # prints one of the chosen rec in list
-
-            rno = ch[0]
-            rname = ch[1]  # due to unpacking the val not printed in list format
-            rmark = ch[2]
-
-            print(rno, rname, rmark, end="\t")
-
-
-binary_read()
+import pickle
+
+
+def binary_read():
+    with open("studrec.dat", "rb") as b:
+        stud = pickle.load(b)
+        print(stud)
+
+        # prints the whole record in nested list format
+        print("contents of binary file")
+
+        for ch in stud:
+            print(ch)  # prints one of the chosen rec in list
+
+            rno = ch[0]
+            rname = ch[1]  # due to unpacking the val not printed in list format
+            rmark = ch[2]
+
+            print(rno, rname, rmark, end="\t")
+
+
+binary_read()

1 File handle/File handle binary/File handle binary read (record in non list form).py renamed to 1 File handle/File handle binary/read.py

@@ -1,20 +1,21 @@
 # binary file to search a given record
 
 import pickle
+from dotenv import load_dotenv
 
 
-def binary_search():
-    with open("studrec.dat", "rb") as F:
+def search():
+    with open("student_records.pkl", "rb") as F:
         # your file path will be different
-        search = 0
+        search = True
         rno = int(input("Enter the roll number of the student"))
 
         for i in pickle.load(F):
             if i[0] == rno:
                 print(f"Record found successfully\n{i}")
-                search = 1
+                search = False
 
-        if search == 0:
+        if search:
             print("Sorry! record not found")
 
 

1 File handle/File handle binary/search record in binary file.py

@@ -0,0 +1,32 @@
+# Updating records in a binary file
+# ! Have a .env file please
+import pickle
+import os
+from dotenv import load_dotenv
+
+base = os.path.dirname(__file__)
+load_dotenv(os.path.join(base, ".env"))
+student_record = os.getenv("STUDENTS_RECORD_FILE")
+
+
+def update():
+    with open(student_record, "rb") as F:
+        S = pickle.load(F)
+        found = False
+        rno = int(input("enter the roll number you want to update"))
+
+        for i in S:
+            if rno == i[0]:
+                print(f"the currrent name is {i[1]}")
+                i[1] = input("enter the new name")
+                found = True
+                break
+
+        if found:
+            print("Record not found")
+
+        with open(student_record, "wb") as F:
+            pickle.dump(S, F)
+
+
+update()

1 File handle/File handle binary/update2.py

@@ -0,0 +1 @@
+STUDENTS_RECORD_FILE= "student_records.pkl"

file_handle/File handle binary/.env

@@ -0,0 +1,40 @@
+# updating records in a binary file
+
+import pickle
+import os
+
+base = os.path.dirname(__file__)
+from dotenv import load_dotenv
+
+load_dotenv(os.path.join(base, ".env"))
+student_record = os.getenv("STUDENTS_RECORD_FILE")
+
+## ! Understand how pandas works internally
+
+
+def update():
+    with open(student_record, "rb") as File:
+        value = pickle.load(File)
+        found = False
+        roll = int(input("Enter the roll number of the record"))
+
+        for i in value:
+            if roll == i[0]:
+                print(f"current name {i[1]}")
+                print(f"current marks {i[2]}")
+                i[1] = input("Enter the new name")
+                i[2] = int(input("Enter the new marks"))
+                found = True
+
+        if not found:
+            print("Record not found")
+
+    with open(student_record, "wb") as File:
+        pickle.dump(value, File)
+
+
+update()
+
+# ! Instead of AB use WB?
+# ! It may have memory limits while updating large files but it would be good
+# ! Few lakhs records would be fine and wouldn't create any much of a significant issues