Sunday 26 June 2022

P#32 Reg expression

To find a pattern in a statement

match = re.search('love', 'i love you all')

if match:
    print('found love')
else:
    print('love Not found')

# found love

match = re.search('love', 'i leave you all')

if match:
    print('found love')
else:
    print('love Not found')

# love Not found

 ## . = any char but \n
match = re.search(r'..ve', 'i love you all') # found,
print(match)

To match email

 to check up Google Account
str = 'hello I am so& so i have account you@google.com'
match = re.search(r'\w+@\w+', str)
if match:
    print(match.group()) #you@google

match = re.search(r'[\w.-]+@[\w.-]+', str)
if match:
    print(match.group())  ## 'you@google.com'

To Validate IFSC code in banks

import re
def isValidIFSCode(str):
    # Regex to check valid IFSC Code.
    regex = "^[A-Z]{4}0[A-Z0-9]{6}$"  # 4 Alphabets,0, 
    # Compile the ReGex
    p = re.compile(regex)
    # If the string is empty
    # return false
    if (str == None):
        return False
    # Return if the string
    # matched the ReGex
    if (re.search(p, str)):
        return True
    else:
        return False
# Driver code
# Test Case 1:
str1 = "SBIN0125620"
print(isValidIFSCode(str1))

# Test Case 2:
str2 = "SBIN0125"
print(isValidIFSCode(str2))

# Test Case 3:
str3 = "1234SBIN012"
print(isValidIFSCode(str3))

# Test Case 4:
str4 = "SBIN7125620"
print(isValidIFSCode(str4))

# This code is contributed by avanitrachhadiya2155

"""
True
False
False
False
"""

Please Note:


# regex = "^[A-Z]{4}0[A-Z0-9]{6}$";
# Where: 
# ^ represents the starting of the string.
# [A-Z]{4} represents the first four characters should be upper case alphabets.
# 0 represents the fifth character should be 0.
# [A-Z0-9]{6} represents the next six characters usually numeric, but can also be alphabetic.
# $ represents the ending of the string.

To test Pin Code

import re

def isValidPinCode(pinCode):
    # Regex to check valid pin code
    # of India.
    regex = "^[1-9]{1}[0-9]{2}\\s{0,1}[0-9]{3}$";

    # Compile the ReGex
    p = re.compile(regex);

    # If the pin code is empty
    # return false
    if (pinCode == ''):
        return False;

    # Pattern class contains matcher() method
    # to find matching between given pin code
    # and regular expression.
    m = re.match(p, pinCode);

    # Return True if the pin code
    # matched the ReGex else False
    if m is None:
        return False
    else:
        return True



# check Driver code
if __name__ == "__main__":
    # Test case 1
    num1 = "625001";
    print(num1, ": ", isValidPinCode(num1));

    # Test case 2:
    num2 = "625 001";
    print(num2, ": ", isValidPinCode(num2));

    # Test case 3:
    num3 = "0625 001";
    print(num3, ": ", isValidPinCode(num3));

    # Test case 4:
    num4 = "6250001";
    print(num4, ": ", isValidPinCode(num4));

Result


"""
625001 :  True
625 001 :  True
0625 001 :  False
6250001 :  False
"""

To check PANCARD in India


# To Valiate pan Card

import re

def checkPanCard():
        import re


        def isValidPanCardNo(panCardNo):

            # PAN Card number
            regex = "[A-Z]{5}[0-9]{4}[A-Z]{1}"

            # Compile the ReGex
            p = re.compile(regex)

            # If the PAN Card number
            # is empty return false
            if(panCardNo == None):
                return False

            # Return if the PAN Card number
            # matched the ReGex
            if(re.search(p, panCardNo) and
            len(panCardNo) == 10):
                return True
            else:
                return False

        # Driver Code.


        # Test Case 1:
        str1 = "AFGHA2318J"
        print(isValidPanCardNo(str1),' ',str1)

        # Test Case 2:
        str2 = "23AFGHN18J"
        print(isValidPanCardNo(str2),str2)

        # Test Case 3:
        str3 = "AFGHA2318JM"
        print(isValidPanCardNo(str3),str3)

        # Test Case 4:
        str4 = "AFGHA23184"
        print(isValidPanCardNo(str4),str4)

        # Test Case 5:
        str5 = "AFGHA 23184"
        print(isValidPanCardNo(str5),str5)

checkPanCard()
"""
True   AFGHA2318J
False 23AFGHN18J
False AFGHA2318JM
False AFGHA23184
False AFGHA 23184
"""

P#31 Magic Methods

Magic or Dunder Methods

Methods having two prefix and suffix underscores in the method name.

Dunder here means “Double Under (Underscores)”

Sample Method:

# declare our test string class
class Str:

    # magic method to initiate object
    def __init__(self, string):
        self.string = string


# Driver Code
if __name__ == '__main__':
    # object creation
    s1 = Str('Hello Python')

    # print object location
    print(s1)

To print __ methods of int

print(dir(int))


# Result

"""
['__abs__', '__add__', '__and__', '__bool__', '__ceil__', '__class__',
 '__delattr__', '__dir__', '__divmod__', '__doc__', '__eq__', '__float__', 
 '__floor__', '__floordiv__', '__format__', '__ge__', '__getattribute__', 
 '__getnewargs__', '__gt__', '__hash__', '__index__', '__init__', '__init_subclass__',
  '__int__', '__invert__', '__le__', '__lshift__', '__lt__', '__mod__', '__mul__', 
  '__ne__', '__neg__', '__new__', '__or__', '__pos__', '__pow__', '__radd__', '__rand__',
  '__rdivmod__', '__reduce__', '__reduce_ex__', '__repr__', '__rfloordiv__', '__rlshift__',
  '__rmod__', '__rmul__', '__ror__', '__round__', '__rpow__', '__rrshift__', '__rshift__', '__rsub__', '__rtruediv__',
  '__rxor__', '__setattr__', '__sizeof__', '__str__', '__sub__', '__subclasshook__', '__truediv__',
  '__trunc__', '__xor__', 'as_integer_ratio', 'bit_length', 'conjugate', 'denominator', 'from_bytes', 'imag', 
  'numerator', 'real', 'to_bytes']
"""

Important Magic Methods

The following tables list important magic methods in Python 3.

Initialization and Construction	Description
__new__(cls, other)	To get called in an object's instantiation.
__init__(self, other)	To get called by the __new__ method.
__del__(self)	Destructor method.

Unary operators and functions	Description
__pos__(self)	To get called for unary positive e.g. +someobject.
__neg__(self)	To get called for unary negative e.g. -someobject.
__abs__(self)	To get called by built-in abs() function.
__invert__(self)	To get called for inversion using the ~ operator.
__round__(self,n)	To get called by built-in round() function.
__floor__(self)	To get called by built-in math.floor() function.
__ceil__(self)	To get called by built-in math.ceil() function.
__trunc__(self)	To get called by built-in math.trunc() function.

Augmented Assignment	Description
__iadd__(self, other)	To get called on addition with assignment e.g. a +=b.
__isub__(self, other)	To get called on subtraction with assignment e.g. a -=b.
__imul__(self, other)	To get called on multiplication with assignment e.g. a *=b.
__ifloordiv__(self, other)	To get called on integer division with assignment e.g. a //=b.
__idiv__(self, other)	To get called on division with assignment e.g. a /=b.
__itruediv__(self, other)	To get called on true division with assignment
__imod__(self, other)	To get called on modulo with assignment e.g. a%=b.
__ipow__(self, other)	To get called on exponentswith assignment e.g. a **=b.
__ilshift__(self, other)	To get called on left bitwise shift with assignment e.g. a<<=b.
__irshift__(self, other)	To get called on right bitwise shift with assignment e.g. a >>=b.
__iand__(self, other)	To get called on bitwise AND with assignment e.g. a&=b.
__ior__(self, other)	To get called on bitwise OR with assignment e.g. a\|=b.
__ixor__(self, other)	To get called on bitwise XOR with assignment e.g. a ^=b.

Type Conversion Magic Methods	Description
__int__(self)	To get called by built-int int() method to convert a type to an int.
__float__(self)	To get called by built-int float() method to convert a type to float.
__complex__(self)	To get called by built-int complex() method to convert a type to complex.
__oct__(self)	To get called by built-int oct() method to convert a type to octal.
__hex__(self)	To get called by built-int hex() method to convert a type to hexadecimal.
__index__(self)	To get called on type conversion to an int when the object is used in a slice expression.
__trunc__(self)	To get called from math.trunc() method.

String Magic Methods	Description
__str__(self)	To get called by built-int str() method to return a string representation of a type.
__repr__(self)	To get called by built-int repr() method to return a machine readable representation of a type.
__unicode__(self)	To get called by built-int unicode() method to return an unicode string of a type.
__format__(self, formatstr)	To get called by built-int string.format() method to return a new style of string.
__hash__(self)	To get called by built-int hash() method to return an integer.
__nonzero__(self)	To get called by built-int bool() method to return True or False.
__dir__(self)	To get called by built-int dir() method to return a list of attributes of a class.
__sizeof__(self)	To get called by built-int sys.getsizeof() method to return the size of an object.

Attribute Magic Methods	Description
__getattr__(self, name)	Is called when the accessing attribute of a class that does not exist.
__setattr__(self, name, value)	Is called when assigning a value to the attribute of a class.
__delattr__(self, name)	Is called when deleting an attribute of a class.

Operator Magic Methods	Description
__add__(self, other)	To get called on add operation using + operator
__sub__(self, other)	To get called on subtraction operation using - operator.
__mul__(self, other)	To get called on multiplication operation using * operator.
__floordiv__(self, other)	To get called on floor division operation using // operator.
__truediv__(self, other)	To get called on division operation using / operator.
__mod__(self, other)	To get called on modulo operation using % operator.
__pow__(self, other[, modulo])	To get called on calculating the power using ** operator.
__lt__(self, other)	To get called on comparison using < operator.
__le__(self, other)	To get called on comparison using <= operator.
__eq__(self, other)	To get called on comparison using == operator.
__ne__(self, other)	To get called on comparison using != operator.
__ge__(self, other)	To get called on comparison using >= operator.

P#30 H/W Internals and Profiling

To know System Information through Python

# Know system Information
# pip install wmi

import wmi

computer = wmi.WMI()
our_system = computer.Win32_ComputerSystem()[0]

print(f"Manufacturer: {our_system.Manufacturer}")
print(f"Model: {our_system. Model}")
print(f"Name: {our_system.Name}")
print(f"NumberOfProcessors: {our_system.NumberOfProcessors}")
print(f"SystemType: {our_system.SystemType}")
print(f"SystemFamily: {our_system.SystemFamily}")
""" Output from my system:
Manufacturer: Dell Inc.

Model: Vostro 3888

Name: MECH1

NumberOfProcessors: 1

SystemType: x64-based PC

SystemFamily: Vostro
"""

Simple System info Python program using platform

# importing module
import platform

# dictionary
info = {}

# platform details
platform_details = platform.platform()

# adding it to dictionary
info["platform details"] = platform_details

# system name
system_name = platform.system()

# adding it to dictionary
info["system name"] = system_name

# processor name
processor_name = platform.processor()

# adding it to dictionary
info["processor name"] = processor_name

# architectural detail
architecture_details = platform.architecture()

# adding it to dictionary
info["architectural detail"] = architecture_details

# printing the details
for i, j in info.items():
   print(i, " - ", j)

"""
platform details  -  Windows-10-10.0.19043-SP0
system name  -  Windows
processor name  -  Intel64 Family 6 Model 165 Stepping 3, GenuineIntel
architectural detail  -  ('64bit', 'WindowsPE')

Process finished with exit code 0
"""

Hardware Information using PSUTIL

import psutil

#Physical cores
print(f"Number of physical cores: {psutil.cpu_count(logical=False)}")
#Logical cores
print(f"Number of logical cores: {psutil.cpu_count(logical=True)}")

#Current frequency
print(f"Current CPU frequency: {psutil.cpu_freq().current}")
#Min frequency
print(f"Min CPU frequency: {psutil.cpu_freq().min}")
#Max frequency
print(f"Max CPU frequency: {psutil.cpu_freq().max}")
# cpu util
#System-wide CPU utilization
print(f"Current CPU utilization: {psutil.cpu_percent(interval=1)}")
#System-wide per-CPU utilization
print(f"Current per-CPU utilization: {psutil.cpu_percent(interval=1, percpu=True)}")

#ram details
#Total RAM
print(f"Total RAM installed: {round(psutil.virtual_memory().total/1000000000, 2)} GB")
#Available RAM
print(f"Available RAM: {round(psutil.virtual_memory().available/1000000000, 2)} GB")
#Used RAM
print(f"Used RAM: {round(psutil.virtual_memory().used/1000000000, 2)} GB")
#RAM usage
print(f"RAM usage: {psutil.virtual_memory().percent}%")

Results


"""
Number of physical cores: 4
Number of logical cores: 8
Current CPU frequency: 3600.0
Min CPU frequency: 0.0
Max CPU frequency: 3600.0
Current CPU utilization: 4.2
Current per-CPU utilization: [15.7, 0.0, 25.0, 0.0, 4.5, 0.0, 1.5, 1.6]
Total RAM installed: 8.33 GB
Available RAM: 1.58 GB
Used RAM: 6.75 GB
RAM usage: 81.0%
"""

Disk and N/W Information using Python

# Disk Usage

import psutil
import platform
from datetime import datetime

def get_size(bytes, suffix="B"):
    """
    Scale bytes to its proper format
    e.g:
        1253656 => '1.20MB'
        1253656678 => '1.17GB'
    """
    factor = 1024
    for unit in ["", "K", "M", "G", "T", "P"]:
        if bytes < factor:
            return f"{bytes:.2f}{unit}{suffix}"
        bytes /= factor

# Disk Information
print("="*40, "Disk Information", "="*40)
print("Partitions and Usage:")
# get all disk partitions
partitions = psutil.disk_partitions()
for partition in partitions:
    print(f"=== Device: {partition.device} ===")
    print(f"  Mountpoint: {partition.mountpoint}")
    print(f"  File system type: {partition.fstype}")
    try:
        partition_usage = psutil.disk_usage(partition.mountpoint)
    except PermissionError:
        # this can be catched due to the disk that
        # isn't ready
        continue
    print(f"  Total Size: {get_size(partition_usage.total)}")
    print(f"  Used: {get_size(partition_usage.used)}")
    print(f"  Free: {get_size(partition_usage.free)}")
    print(f"  Percentage: {partition_usage.percent}%")
# get IO statistics since boot
disk_io = psutil.disk_io_counters()
print(f"Total read: {get_size(disk_io.read_bytes)}")
print(f"Total write: {get_size(disk_io.write_bytes)}")

# N/w
# Network information
print("="*40, "Network Information", "="*40)
# get all network interfaces (virtual and physical)
if_addrs = psutil.net_if_addrs()
for interface_name, interface_addresses in if_addrs.items():
    for address in interface_addresses:
        print(f"=== Interface: {interface_name} ===")
        if str(address.family) == 'AddressFamily.AF_INET':
            print(f"  IP Address: {address.address}")
            print(f"  Netmask: {address.netmask}")
            print(f"  Broadcast IP: {address.broadcast}")
        elif str(address.family) == 'AddressFamily.AF_PACKET':
            print(f"  MAC Address: {address.address}")
            print(f"  Netmask: {address.netmask}")
            print(f"  Broadcast MAC: {address.broadcast}")
# get IO statistics since boot
net_io = psutil.net_io_counters()
print(f"Total Bytes Sent: {get_size(net_io.bytes_sent)}")
print(f"Total Bytes Received: {get_size(net_io.bytes_recv)}")

Result:


"""
======================================== Disk Information ========================================
Partitions and Usage:
=== Device: C:\ ===
  Mountpoint: C:\
  File system type: NTFS
  Total Size: 194.70GB
  Used: 111.24GB
  Free: 83.46GB
  Percentage: 57.1%
=== Device: D:\ ===
  Mountpoint: D:\
  File system type: NTFS
  Total Size: 736.20GB
  Used: 4.03GB
  Free: 732.16GB
  Percentage: 0.5%
Total read: 61.63GB
Total write: 46.68GB
======================================== Network Information ========================================
=== Interface: Local Area Connection* 11 ===
=== Interface: Local Area Connection* 11 ===
  IP Address: 169.254.62.94
  Netmask: 255.255.0.0
  Broadcast IP: None
=== Interface: Local Area Connection* 11 ===
=== Interface: Local Area Connection* 12 ===
=== Interface: Local Area Connection* 12 ===
  IP Address: 169.254.72.255
  Netmask: 255.255.0.0
  Broadcast IP: None
=== Interface: Local Area Connection* 12 ===
=== Interface: Ethernet ===
=== Interface: Ethernet ===
  IP Address: 172.20.24.131
  Netmask: 255.255.0.0
  Broadcast IP: None
=== Interface: Ethernet ===
=== Interface: Wi-Fi 2 ===
=== Interface: Wi-Fi 2 ===
  IP Address: 172.20.29.139
  Netmask: 255.255.0.0
  Broadcast IP: None
=== Interface: Wi-Fi 2 ===
=== Interface: Loopback Pseudo-Interface 1 ===
  IP Address: 127.0.0.1
  Netmask: 255.0.0.0
  Broadcast IP: None
=== Interface: Loopback Pseudo-Interface 1 ===
Total Bytes Sent: 366.06MB
Total Bytes Received: 4.38GB
"""

Measuring Running Time in Python #1

import timeit
time_test = timeit.repeat('[x**0.5 for x in range(1000)]', number=10000)
print(time_test)

Result:

"""
[1.415492, 1.3847563, 1.3762589999999997, 1.3683869, 1.3789484000000005]
"""

# importing cProfile
import cProfile

cProfile.run("10 + 10")

"""
   3 function calls in 0.000 seconds

   Ordered by: standard name

   ncalls  tottime  percall  cumtime  percall filename:lineno(function)
        1    0.000    0.000    0.000    0.000 <string>:1(<module>)
        1    0.000    0.000    0.000    0.000 {built-in method builtins.exec}
        1    0.000    0.000    0.000    0.000 {method 'disable' of '_lsprof.Profiler' objects}
"""

Function Profiling code and the corresponding output

# Function Profiling
import cProfile

def f():
   print("Hello Python World Profiling")
cProfile.run('f()')

         5 function calls in 0.000 seconds

   Ordered by: standard name

   ncalls  tottime  percall  cumtime  percall filename:lineno(function)
        1    0.000    0.000    0.000    0.000 <string>:1(<module>)
        1    0.000    0.000    0.000    0.000 ex1-scit.py:252(f)
        1    0.000    0.000    0.000    0.000 {built-in method builtins.exec}
        1    0.000    0.000    0.000    0.000 {built-in method builtins.print}
        1    0.000    0.000    0.000    0.000 {method 'disable' of '_lsprof.Profiler' objects}