## First Steps Towards Experimental Design in Evaluating Layout Layout Algorithms: Wire Length versus Wire Crossing in Linear Placement Optimization (1998)

Venue: | October), CBL, CS Dept., NCSU, Box 7550 |

Citations: | 2 - 2 self |

### BibTeX

@TECHREPORT{Ghosh98firststeps,

author = {Debabrata Ghosh and Franc Brglez and Matthias Stallmann},

title = {First Steps Towards Experimental Design in Evaluating Layout Layout Algorithms: Wire Length versus Wire Crossing in Linear Placement Optimization},

institution = {October), CBL, CS Dept., NCSU, Box 7550},

year = {1998}

}

### OpenURL

### Abstract

. This report introduces an experimental design that discovers a new relationship between a cell placement for minimized wire crossing in bipartite (two-layer) graphs and a cell placement in linear arrangement, optimized for minimum total wire length as measured after rectilinear routing in a single channel. We introduce hypercrossing, a new crossing model for graphs, and demonstrate that the total wire length in the channel, as measured after routing, has a positive linear correlation with the total hypercrossing, and a coefficient of correlation of near 100%. While heuristics to directly minimize total hypercrossing are yet to be invented, our experiments show that the minimization of total (regular) wire crossing leads to placements with significantly reduced wire length and wiring area. A methodology and new datasets are now available to determine, with statistical significance, which of the two cost function classes will yield a better placement in general: costs based on the mode...

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