A directory structure organizes related source artifacts and project data into predictable folders. As a project grows, separate folders for related files make code easier to read, maintain, and navigate. section 1.1.1
Create a portable data directory
Use pathlib to create a directory, verify it exists, and construct paths without hard-coding platform-specific separators: from pathlib import Path data_folder = Path("data") data_folder.mkdir() assert data_folder.exists() for subject_id in [123, 124, 125]: filepath = data_folder / f"subject_{subject_id}.dat" with open(filepath, "w") as file: file.write(f"Data for subject {subject_id}") The / operation works across Windows and macOS, unlike manually written paths such as data\\subject_123.dat. section 11.4.1
A useful directory workflow separates discovery, organization, and access:
- Create missing nested folders with mkdir(parents=True, exist_ok=True). section 11.4.3
- Find related files with glob, retrieve their names with name, and move them by renaming each path to a target path. section 11.4.3
- For files inside subdirectories, use parent for the directory, stem for the filename without its extension, and suffix for the extension. section 11.5.1
Listing 11.16 Moving files to a target folder
subject_ids = [123, 124, 125]
data_folder = Path("data")
for subject_id in subject_ids:
subject_folder = Path(f"subjects/subject_{subject_id}")
subject_folder.mkdir(parents=True, exist_ok=True) #1
for subject_file in data_folder.glob(f"*{subject_id}*"):
filename = subject_file.name #2
target_path = subject_folder / filename #3
_ = subject_file.rename(target_path)
print(f"Moving {filename} to {target_path}")
# output the following lines:
Moving subject_123.config to subjects/subject_123/subject_123.config
Moving subject_123.dat to subjects/subject_123/subject_123.dat
Moving subject_123.txt to subjects/subject_123/subject_123.txt
Moving subject_124.config to subjects/subject_124/subject_124.config
Moving subject_124.dat to subjects/subject_124/subject_124.dat
Moving subject_124.txt to subjects/subject_124/subject_124.txt
Moving subject_125.dat to subjects/subject_125/subject_125.dat
Moving subject_125.config to subjects/subject_125/subject_125.config
Moving subject_125.txt to subjects/subject_125/subject_125.txt
The worked listing groups each participant's configuration, data, and text files under subjects/subject_ID folders and prints the resulting moves. section 11.4.3
A well-structured project keeps related artifacts together while preserving consistent layouts across files. Regularly checking names, imports, file placement, and folder organization supports readable and maintainable code. section 1.1.1
