iaeste-python

Intro to Jupyter

Goto Anaconda Prompt
Enter 'jupyter notebook'
It opens Jupyter Notebook which uses localhost

What is Jupter Notebook

Jupyter is similar IDE like VSCode

Intro to Python

Substitution of variables in Strings

Since Python doesn't have substitution of variables, we need to use a function called format() to redefine variables in a string

eg.

s='{name} has {n} messages'
s=s.format(name='Nikesh',n=37)
print(s)

Text-wrapping and indentation

By importing textwrap we can limit area spanned by a string in the console and we can provide initial indentation as well as subsequent indentation

eg.

s='Hello World'
print(textwrap.fill(s,1))    #Wraps the text 
print(textwrap.fill(s,1,initial_indent='  - '))   #Adds ' - ' at the start of each line
print(textwrap.fill(s,1,subsequent_indent='  - '))    #Adds ' - ' after every line except the first one

Replacing HTML/XML entities such as &entity; / &#code; with corresponding text Alternatively, you need to produce the text but escape certain characters (<,>,& etc)

So this basically converts the text to its HTML form

s = 'Elements are written as "<tag>text</tag>".'  #allocation starts from right to left
import html
print(s)
print(html.escape(s))
print(html.escape(s,quote=False)) #Disabling escape of quotes

Rounding off

This is done with the help of round(x,y) where x is the integer/float and y is the decimal points to be rounded off to given power of 10

round(1.27,1)
round(-1.27,1)
round(1.2563,3)
a=12456
round(a,-3) #prints 12000 which is rounding  off to 10e3

Many time format is used for precision formatting

x=1.23456789
format(x,'0.3f')
'value is {:0.3f}'.format(x)

Converting integers to binary, octal, hexadecimal

The program below converts to decimal, binary and so on

x=12345
bin(x)  #Converts to binary - Prints  '0b11000000111001'
oct(x)  #Converts to Octal  - Prints  '0o30071'
hex(x)  #Converts to Hexadecimal  - Prints  '0x3039'

The program below does the same as above but removes the initial

format(x,'b') #Prints 11000000111001
format(x,'o') #Prints 30071
format(x,'x') #Prints 3039

Below the binary contains negative sign

x=-1234
format(x,'b')

Working with Linux

Level of work

hadoop

Horton

VMWare

Windows OS

We use WinSCP to create a channel between the OS and server

Some Important commands

hadoop fs -mkdir /bingo ^the one which processses data ^file system ^directory name
hadoop fs -ls / ^lists the system
hadoop fs -copyFromLocal /root/Test/4300.txt /bingo

or

hadoop fs cp /root/Test/4300.txt /bingo
hadoop fs -cat /bingo/4300.txt ^categorizes
cd java-files
sh java-compile.sh WordCount.java
hadoop fs WordCOunt.jar org.apache.hadoop.examples.WordCount /bingo/4300.txt /testout
hadoop fs -cat /testout/part-r-00000
hadoop fs -get /testout/part* /root/xyz

nikeplusdash / iaeste-python