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PLinOpt: C++ routines handling linear, bilinear & trilinear programs

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Authors: Jean-Guillaume Dumas, Bruno Grenet, Clément Pernet, Alexandre Sedoglavic

• J-G. Dumas, C. Pernet, A. Sedoglavic; Strassen's algorithm is not optimally accurate, ISSAC 2024, Raleigh, NC USA, pp. 254-263.
• J-G. Dumas, B. Grenet; In-place accumulation of fast multiplication formulae, ISSAC 2024, Raleigh, NC USA, pp. 16-25.

Requirements:

• C++, pkg-config
• LinBox, dev: headers & library (LinBox version ≥ 1.7.0; givaro version ≥ 4.2.0)

Installation:

• Requires some distribution packages like: sudo apt install git make g++ pkg-config liblinbox-dev (sometimes also sudo apt install libntl-dev libiml-dev libflint-dev).
• Then just run make, in order to produce the following executable programs
• See also bin/auto-docker.run
• make check, will run correctness programs on the examples files in the data directory

From matrices to programs:

bin/optimizer	produces a small program computing a linear transformation
bin/sparsifier	factors an MxN matrix into a sparser one, times an NxN matrix
bin/factorizer	factors an MxN matrix into a sparser MxK, times an KxN matrix
bin/inplacer	produces an in-place program from a linear transformation
bin/trilplacer	produces an in-place program from a trilinear transformation

Optimizing programs:

bin/compacter	rewrites a simple program using less variables
bin/transpozer	transposes a program, via Tellegen's transposition principle

Tools:

bin/matrix-transpose	transposes a matrix from an SMS file
bin/sms2pretty	pretty prints a matrix from a file
bin/PMchecker	asserts correctness of program, with respect to a matrix
bin/MMchecker	asserts correctness of trilinear program for matrix-multiplication

Matrix Syntax: SMS format (numbering from 1 to m), see Sparse Integer Matrix Collection

Starts with	m	n	'R'
then	i	j	value
ends with	0	0	0

• data directory contains example matrices in this format

Program Syntax:

• Line by line
• Operators are: :=, +, -, *, /, ;
• Each line not containing := is ignored
• Everything after ';' is ignored
• Everything not an operator, nor spaces, is a variable:
  • Constant variables start by c
  • Input variables start by i
  • Output variables start by o
• Program must start by loading each input variable into a temporary t1:=i1

Examples:

• ./bin/sms2pretty data/Lw.sms data/Rw.sms data/Pw.sms: pretty print HM representation of Strassen-Winograd's fast 2x2 multiplication algorithm
• ./bin/matrix-transpose data/Pw.sms: the transposed matrix
• ./bin/MMchecker data/Lw.sms data/Rw.sms data/Pw.sms: probabilistically checking Strassen-Winograd's matrix-multiplication algorithm
• ./bin/MMchecker data/Lo.sms data/Ro.sms data/Po.sms 32 3 1013: probabilistically checking matrix-multiplication algorithm using 32 bits random elements and 1013 as a placeholder for sqrt(3)
• ./bin/optimizer data/cyclic.sms: a program computing that matrix-vector product
• ./bin/optimizer data/Rr.sms -q 3: a program computing that matrix-vector product modulo 3
• ./bin/transpozer data/test.prg: a program computing the transposed program
• ./bin/compacter data/test.prg: a more compact program
• ./bin/optimizer -D data/Pi.sms: a program computing that matrix-vector product
• ./bin/optimizer data/Li.sms | ./bin/compacter -s: a compact program computing that matrix-vector product
• ./bin/matrix-transpose data/Pi.sms | ./bin/optimizer -K | ./bin/transpozer: a program computing that matrix-vector product
• ./bin/sparsifier -c 4 data/Lr.sms: a factorization of that matrix into a sparser one (also with many 1s) by an alternate change of basis (CoB) 4x4 matrix
• ./bin/factorizer -k 6 data/Lr.sms: a factorization of that matrix into a 7x6 sparser one by a 6x4 matrix
• ./bin/inplacer data/Lw.sms: in-place matrix-vector accumulating multiplication
• ./bin/trilplacer data/Lw.sms data/Rw.sms data/Pw.sms: in-place version of Strassen-Winograd's fast 2x2 accumulating multiplication
• ./bin/trilplacer data/Lk.sms data/Rk.sms data/Pk.sms -e: in-place version of Karatsuba's fast accumulating polynomial multiplication
• ./bin/optimizer -q 17 data/Lo.sms | ./bin/compacter -s | ./bin/PMchecker -q 17 -M data/Lo.sms: creates a program for Lo.sms modulo 17, compacts it with less variables, then checks consistency