Featured Post

Top Questions People Ask About Pandas, NumPy, Matplotlib & Scikit-learn — Answered!

Image
 Whether you're a beginner or brushing up on your skills, these are the real-world questions Python learners ask most about key libraries in data science. Let’s dive in! 🐍 🐼 Pandas: Data Manipulation Made Easy 1. How do I handle missing data in a DataFrame? df.fillna( 0 ) # Replace NaNs with 0 df.dropna() # Remove rows with NaNs df.isna(). sum () # Count missing values per column 2. How can I merge or join two DataFrames? pd.merge(df1, df2, on= 'id' , how= 'inner' ) # inner, left, right, outer 3. What is the difference between loc[] and iloc[] ? loc[] uses labels (e.g., column names) iloc[] uses integer positions df.loc[ 0 , 'name' ] # label-based df.iloc[ 0 , 1 ] # index-based 4. How do I group data and perform aggregation? df.groupby( 'category' )[ 'sales' ]. sum () 5. How can I convert a column to datetime format? df[ 'date' ] = pd.to_datetime(df[ 'date' ]) ...

How to Run First Program in Python

When you are a first-time learner of Python, the below commands you can try on windows Python-interpreter. Python is a powerful and multipurpose language.

At the highest level, Python is an interpreted language. And you don't need declarations for:

  1. Variables
  2. Methods
  3. Parameters
  4. Functions

You don't need a compiler. During the run-time, the Python interpreter validates the code and shows-up errors.

How to Run First Program in Python.

$ python        ## Run the Python interpreter
Python 2.7.9 (default, Dec 30 2014, 03:41:42) [GCC 4.1.2 20080704 
(Red Hat 4.1.2-55)] on linux2Type "help", "copyright", 
"credits" or "license" for more information.
>>> a = 6       ## set a variable in this interpreter session
>>> a           ## entering an expression prints its value
6
>>> a + 2
8
>>> a = 'hi'    ## 'a' can hold a string just as well
>>> a'hi'
>>> len(a)      ## call the len() function on a string
2
>>> a + len(a)  ## try something that doesn't work
Traceback (most recent call last):
  File "", line 1, in 
TypeError: cannot concatenate 'str' and 'int' objects>>> 
a + str(len(a)) 
## probably what you really wanted
'hi2'
>>> foo         ## try something else that doesn't work
Traceback (most recent call last):
  File "", line 1, in 
NameError: name 'foo' is not defined
>>> ^D          ## type CTRL-d to exit 
(CTRL-z in Windows/DOS terminal)
Sources

Comments

Popular posts from this blog

SQL Query: 3 Methods for Calculating Cumulative SUM

5 SQL Queries That Popularly Used in Data Analysis

Big Data: Top Cloud Computing Interview Questions (1 of 4)