notebook-path-policy

Mathematica output files save automatically to the notebook directory by resolving bare filenames through NotebookDirectory[InputNotebook[]] first, applying a fallback policy to $packageDirectory if the notebook directory is invalid or missing.

Mathematica writes output files to the wrong directory when bare filenames lack a standardized resolution policy. Enforcing a NotebookDirectory-or-$packageDirectory fallback policy directs bare filename outputs to the correct deterministic location instead of unpredictable paths.

Explicit absolute paths receive the highest priority and override the NotebookDirectory fallback policy entirely. Providing an absolute path respects user intent by using that exact destination instead of resolving a directory based on the notebook or package location.

Deterministic file output routing in Mathematica notebooks is achieved by enforcing a fallback policy that selects NotebookDirectory for bare filenames, prioritizes absolute paths, and constructs output paths using OS-independent joining to prevent broken filesystem behavior.

Relative path handling in this workflow constructs output paths using OS-independent joining to ensure safe filesystem behavior across platforms. It treats relative outputs as intended for the resolved destination directory selected by the fallback policy.

Use $packageDirectory for output routing when NotebookDirectory[InputNotebook[]] does not exist or is not a valid directory. The fallback policy automatically selects $packageDirectory to ensure outputs still land in a safe, predictable package folder location.