Glob expressions are patterns used to match file names or paths. They are used to specify the files to be read by various file-handling functions, including those in Dask.
A glob expression typically consists of a combination of literal characters and special characters, which have different meanings. Here are some common special characters used in glob expressions:
*: matches any number of characters (including zero)?: matches any single character[abc]: matches any one of the specified characters (a, b, or c in this case)[a-z]: matches any character in the specified range (a to z in this case)For example, the glob expression *.txt matches all files in a directory that end with .txt, while the expression file?.txt matches files named file1.txt, file2.txt, and so on.
When using glob expressions in Dask, you can use them as arguments to file-handling functions, such as dask.bag.read_text or dask.dataframe.read_csv. For example, to read all text files in a directory with the file extension .txt, you can use the following code:
import dask.bag as dbmy_bag = db.read_text('/path/to/my/files/*.txt') |
This will read all text files in the /path/to/my/files directory that end with .txt and create a Dask bag containing the lines of all the files.