Code Bits

Search our repository of helpful code snippets for data processing and analysis (using Python/Pandas and SQL)

Add new column to Pandas dataframe with default value Break a long line into multiple lines in Python Change order of columns in a Pandas dataframe Concatenate two arrays (lists) in Python Convert column in Pandas dataframe to a list Convert strings to lower and uppercase in Python Convert to number to float, int, and string in Python Count the frequency a value occurs in Pandas dataframe Create a new column in Pandas dataframe Create a pivot table from a Pandas dataframe Create and run a function in Python Drop duplicate rows in Pandas based on column value Dropping rows/columns from a Pandas dataframe Extract month and year from column in Pandas, create new column Find and replace characters in Pandas dataframe columns Generate a for loop in Python Generate current time in python Get row and column count for Pandas dataframe Get the mean and median from a Pandas column in Python If and else statements in Python Importing data from MongoDB into Python (Pandas) Iterating over rows in Pandas dataframe Merge two dataframes together in Pandas Open a browser URL using Python Read data from csv to Pandas Rename columns in a Pandas dataframe Replace all NaN values with 0's in a column of Pandas dataframe Return the number of columns in a Pandas dataframe Select Pandas dataframe rows between two dates Select rows from a Pandas DataFrame based on values in a column Slice a string in python (right, left, mid equivalents) Sort a dataframe in Pandas based on multiple columns Web scraping with python using Beautiful Soup Insert multiple rows in a single SQL query Finding duplicate values in a SQL table Create a case statement in SQL Concatenate multiple columns in SQL Select data from SQL table based on multiple conditions Correlating stocks using Python and visualizing correlation coefficients Count the # of unique records in a table using SQL Introduction to time series forecasting with FB Prophet Convert a list of Python dictionaries to a Pandas dataframe Check whether a Python string contains another string Remove NaN values from a Pandas series Concatenate Pandas dataframes (like a union function in SQL) Search pandas column with string contains and does not contain Create Pandas dataframe with random numbers Remove duplicate columns by name in Pandas Dynamically update a plot in iPython notebook Count distinct in Pandas aggregation Pandas rolling mean in dataframe Sort a Python dictionary by value or key Check if a list is empty in Python Access the index of a Python for loop Slice notation in Python Iterate over dictionaries in Python Time delay in Python script (sleep) Create a bar chart in Python with Matplotlib Create a scatter plot in Python with Matplotlib Create a scatter plot in Python with Seaborn Introduction to Linear Regression using Python Simulating future stock prices using Monte Carlo methods in Python

Complete list of references:

Pandas

• Add new column to Pandas dataframe with default value
• Change order of columns in a Pandas dataframe
• Convert column in Pandas dataframe to a list
• Count the frequency a value occurs in Pandas dataframe
• Create a new column in Pandas dataframe
• Create a pivot table from a Pandas dataframe
• Drop duplicate rows in Pandas based on column value
• Dropping rows/columns from a Pandas dataframe
• Extract month and year from column in Pandas, create new column
• Find and replace characters in Pandas dataframe columns
• Get row and column count for Pandas dataframe
• Get the mean and median from a Pandas column in Python
• Iterating over rows in Pandas dataframe
• Merge two dataframes together in Pandas
• Read data from csv to Pandas
• Rename columns in a Pandas dataframe
• Replace all NaN values with 0's in a column of Pandas dataframe
• Return the number of columns in a Pandas dataframe
• Select Pandas dataframe rows between two dates
• Select rows from a Pandas DataFrame based on values in a column
• Sort a dataframe in Pandas based on multiple columns
• Remove NaN values from a Pandas series
• Concatenate Pandas dataframes (like a union function in SQL)
• Search pandas column with string contains and does not contain
• Create Pandas dataframe with random numbers
• Remove duplicate columns by name in Pandas
• Dynamically update a plot in iPython notebook
• Count distinct in Pandas aggregation
• Pandas rolling mean in dataframe

Python (non-Pandas)

• Break a long line into multiple lines in Python
• Concatenate two arrays (lists) in Python
• Convert strings to lower and uppercase in Python
• Convert to number to float, int, and string in Python
• Create and run a function in Python
• Generate a for loop in Python
• Generate current time in python
• If and else statements in Python
• Importing data from MongoDB into Python (Pandas)
• Open a browser URL using Python
• Slice a string in python (right, left, mid equivalents)
• Web scraping with python using Beautiful Soup
• Correlating stocks using Python and visualizing correlation coefficients
• Introduction to time series forecasting with FB Prophet
• Convert a list of Python dictionaries to a Pandas dataframe
• Check whether a Python string contains another string
• Sort a Python dictionary by value or key
• Check if a list is empty in Python
• Access the index of a Python for loop
• Slice notation in Python
• Iterate over dictionaries in Python
• Time delay in Python script (sleep)
• Create a bar chart in Python with Matplotlib
• Create a scatter plot in Python with Matplotlib
• Create a scatter plot in Python with Seaborn
• Introduction to Linear Regression using Python
• Simulating future stock prices using Monte Carlo methods in Python

SQL

• Insert multiple rows in a single SQL query
• Finding duplicate values in a SQL table
• Create a case statement in SQL
• Concatenate multiple columns in SQL
• Select data from SQL table based on multiple conditions
• Count the # of unique records in a table using SQL

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