ASAP (Annotating Single-cell data matrix by Approximate Pseudo-bulk projection) in R

The goal of ASAP framework:

1. Cell topic annotation should be reasonably fast enough to be integrated with a typical analysis pipeline.

2. The whole algorithm should be accessible to users with modest computing resources (e.g., low memory footprint).

3. Batch adjustment and follow-up analysis should render intuitive (causal) interpretations.