Technology

3 minutes read
To convert time to AM/PM format in pandas, you can use the dt.strftime() method on a datetime column in a pandas DataFrame. First, make sure that the time column is in datetime format by using the pd.to_datetime() function if needed. Then, you can apply the dt.strftime('%I:%M %p') function to convert the time to AM/PM format. This will format the time as hh:mm AM/PM.How to handle timezone when converting time to am/pm in pandas.
3 minutes read
One way to reduce the amount of RAM used by pandas is to load only the necessary columns from the dataset instead of loading the entire dataset. This can be done using the usecols parameter in the read_csv function. Additionally, you can convert columns with high memory usage, such as object data types, to more memory-efficient data types, such as category or numeric types.
3 minutes read
To normalize a JSON file using Pandas, you can start by loading the JSON file into a Pandas DataFrame using the pd.read_json() function. Next, you can use the json_normalize() function from the Pandas library to normalize the JSON data into a flat table structure.This function will recursively extract data from nested JSON objects and arrays, creating separate columns for each level of nesting. This will make it easier to work with the data and perform analysis on it.
3 minutes read
To split a pandas column into two separate columns, you can use the str.split() method along with the expand=True parameter. This will split the column values based on a specified delimiter and expand them into two separate columns. Additionally, you can use the str.get() method to access the individual split values and assign them to new columns. By following these steps, you can efficiently split a pandas column into two separate columns based on your specific requirements.
4 minutes read
To convert a list into a pandas dataframe, you can use the pd.DataFrame() constructor in pandas. Simply pass in the list as an argument to create a dataframe with the list elements as rows. You can also specify column names by passing a list of column names as the columns parameter. This will create a dataframe with the list elements as rows and the specified column names.
2 minutes read
To replace certain values with the mean in pandas, you can first calculate the mean of the column using the mean() function. Then use the replace() function to replace the specific values with the mean value. For example, if you want to replace all occurrences of a specific value "X" with the mean of the column, you can use df['column_name'].replace('X', df['column_name'].mean(), inplace=True).
4 minutes read
To append columns as additional rows in pandas, you can use the melt() function to reshape the DataFrame by converting the columns into rows. This function allows you to specify which columns you want to keep as identifiers and which columns you want to convert into rows.By using the melt() function, you can create a new DataFrame with the columns appended as additional rows. This can be useful for organizing data in a more readable format or preparing it for further analysis.
4 minutes read
Pandas provides extensive functionality for manipulating datetime objects. You can convert string representations of dates and times into datetime objects using the pd.to_datetime() function. Once you have a datetime object, you can access various attributes such as year, month, day, hour, minute, and second.Pandas also allows you to perform operations on datetime objects, such as adding or subtracting time intervals using the pd.DateOffset class.
4 minutes read
To query GraphQL in React with TypeScript, you typically use a library like Apollo Client. First, you need to set up an ApolloClient instance with the appropriate configurations, including the GraphQL endpoint URL. Then, you can use the useQuery hook provided by Apollo Client in your React component to fetch data from the GraphQL server.When using TypeScript, you can define the types of the data returned by the query using interfaces or type aliases.
5 minutes read
After a GraphQL mutation is performed, the cache can be updated in a couple of ways. One common approach is to use the update function provided by Apollo Client's useMutation hook or client.mutate method. Within this function, you can manually update the cache to reflect the changes made by the mutation.Alternatively, you can use the refetchQueries option in the mutation's configuration to automatically refetch specific queries after the mutation has completed.