@@ -90,7 +90,7 @@ than or equal to *net_size_threshold*. The default value for this parameter is 3
****Pending clarification #3: How does hMETIS with nparts = 500 and a nonempty .fix file create so many standard-cell clusters (soft macros)? What explains the variation in cluster area, given that hMETIS is run with UBfactor = 5?*** For example, the Ariane example data shown in Circuit Training’s [test_data](https://github.com/google-research/circuit_training/tree/main/circuit_training/environment/test_data/ariane) has 799 soft macros, although in practice Ariane synthesizes to only approximately (100K +/- 20K) standard cells along with its 133 hard macros. Furthermore, in the Circuit Training data, it is easy to see that all hard macros have identical dimensions 19.26(h) x 29.355(w), but that the 799 soft macros have dimensions in the range \[0.008 , 14.46\](h) x 10.18(w), implying areas that vary across a ~1500X range.
****Update to Pending clarification #3:*** We are glad to see grouping ([clustering](https://github.com/google-research/circuit_training/tree/main/circuit_training/grouping)) added to the Circuit Training GitHub. The new scripts refer to (x,y) coordinates of nodes in the netlist, which leads to further pending clarifications (noted [here](https://github.com/google-research/circuit_training/issues/25)). The solution space for how the input to hypergraph clustering is obtained has expanded. A first level of options is whether (A) a non-physical synthesis tool (e.g., Genus, DesignCompiler or Yosys), or (B) a physical synthesis tool (e.g., Genus iSpatial or DesignCompiler Topological (Yosys cannot perform physical synthesis)), is used to obtain the netlist from starting RTL and constraints. In the regime of (B), to our understanding the commercial physical synthesis tools are invoked with a starting .def that includes macro placement. Thus, we plan to also enable a second level of sub-options for determining this macro placement: (B.1) use the auto-macro placement result from the physical synthesis tool, and (B.2) use a human PD expert (or, OpenROAD RTL-MP) macro placement.
*[June 13]***Update to Pending clarification #3:*** We are glad to see [grouping (clustering)](https://github.com/google-research/circuit_training/tree/main/circuit_training/grouping) added to the Circuit Training GitHub. The new scripts refer to (x,y) coordinates of nodes in the netlist, which leads to further pending clarifications (noted [here](https://github.com/google-research/circuit_training/issues/25)). The solution space for how the input to hypergraph clustering is obtained has expanded. A first level of options is whether **(A) a non-physical synthesis tool** (e.g., Genus, DesignCompiler or Yosys), or **(B) a physical synthesis tool** (e.g., Genus iSpatial or DesignCompiler Topological (Yosys cannot perform physical synthesis)), is used to obtain the netlist from starting RTL and constraints. In the regime of (B), to our understanding the commercial physical synthesis tools are invoked with a starting .def that includes macro placement. Thus, we plan to also enable a second level of sub-options for determining this macro placement: **(B.1)** use the auto-macro placement result from the physical synthesis tool, and **(B.2)** use a human PD expert (or, [OpenROAD RTL-MP](https://github.com/The-OpenROAD-Project/OpenROAD/tree/master/src/mpl2)) macro placement.
## **III. Our Implementation of Hypergraph Clustering.**
