Provided by: libpdl-ccs-perl_1.23.12-1build1_amd64

**NAME**

PDL::CCS - Sparse N-dimensional PDLs with compressed column storage

**SYNOPSIS**

use PDL; use PDL::CCS; ## ... stuff happens ...

**DESCRIPTION**

PDL::CCS is now just a wrapper package which pulls in a number of submodules. See the documentation of the respective modules for details.ModulesPDL::CCS::Nd Perl class for representing large sparse N-dimensional numeric structures using sorted index vector-vectors and a flat vector of non-missing values. Supports a subset of the perl-side PDL API. PDL::CCS::Compat Backwards-compatibility module for Harwell-Boeing compressed row- or column-storage. PDL::CCS::Functions Some useful generic pure-perl functions for dealing directly with CCS-, CRS-, and index-encoded PDLs. PDL::CCS::Utils Low-level generic PDL::PP utilities for Harwell-Boeing encoding and decoding "pointers" along arbitrary dimensions of a sparse PDL given an index list. PDL::CCS::Ops Low-level generic PDL::PP utilities for blockwise alignment of pairs of sparse index- encoded PDLs, useful for implementing binary operations. PDL::CCS::Ufunc Various low-level ufunc (accumulator) utilities for index-encoded PDLs. PDL::CCS::MatrixOps Low-level generic PDL::PP utilities for matrix operations on index-encoded PDLs. PDL::CCS::IO::FastRaw PDL::IO::FastRaw wrappers for PDL::CCS::Nd objects.

**ACKNOWLEDGEMENTS**

Perl by Larry Wall. PDL by Karl Glazebrook, Tuomas J. Lukka, Christian Soeller, and others. Original inspiration and algorithms from the SVDLIBC C library by Douglas Rohde; which is itself based on SVDPACKC by Michael Berry, Theresa Do, Gavin O'Brien, Vijay Krishna and Sowmini Varadhan.

**KNOWN** **BUGS**

· PDL::CCS::Nd supports only a subset of the PDL API (i.e. is not really a PDL). · Binary operations via alignment only work correctly when missing values are annihilators. · Misleading module name: PDL::CCS::Nd objects actually use a native COO (full coordinate list) format rather than CRS (compressed row storage) or CCS (compressed column storage); see <https://en.wikipedia.org/wiki/Sparse_matrix#Coordinate_list_(COO)> for a discussion.

**AUTHOR**

Bryan Jurish <moocow@cpan.org>CopyrightPolicyCopyright (C) 2005-2018 by Bryan Jurish. All rights reserved. This package is free software, and entirely without warranty. You may redistribute it and/or modify it under the same terms as Perl itself.

**SEE** **ALSO**

perl(1),PDL(3perl),PDL::CCS::Nd(3perl),PDL::SVDLIBC(3perl), <https://en.wikipedia.org/wiki/Sparse_matrix>.