Aleph-w

Aleph-w is a library of data structures and algorithms implemented in and for C++.

It contains the most popular data structures: single and double lists, special arrays (dynamic and of bits), many types of trees: multitrees, binary search trees, avl, red-black, randomized, treaps, splay and other interesting types.

Several types of hash tables are implemented: separated chaining, open addressing with linear probing and double function hash; this last one has a garbage collector mechanism that allows freeing deleted entries. Dynamic linear hash tables are implemented too.

The main algorithms on graphs are implemented and with good performance features. Network Flow (maximum and min cost), cut points, topological sort, spanning trees, min paths, etc. The graphs are generic in the sense that they can contain data independent of the algorithm.

The implementation details are not hidden. Each data structure claims how this is implemented. For example, the Aleph-w type DynList represents a dynamic list of items that is implemented with a single linked list. Consequently you directly know that you can not delete in O(1) an item given its address. At the contrary, the data type DynDlist, that represents a list implemented with a double linked list, allows to delete any item in O(1) given its address because the item contains enough context for the deletion.

Most of components of Aleph-w are designed with a minimalist pretension, according to the end to end argument (Saltzer et Al). For example, in the case of binary trees, we first model the binary node, which handles the data storage and link management. Next, we model the tree based on the idea of binary node, without to think in memory management. Finally we model the general binary tree, which manages memory and receives as template parameter the type of tree.

Almost every data structure supports functional programming primitives strongly inspired on the ML standard library: for_each(), all(), exists(), maps(), find_ptr(), foldl(), etc.

Building

Library

The following dependencies are mandatory (the Ubuntu packages names are given):

For having Imake you will need xutils-dev
GNU scientific library: libgsl0-dev
'GNU MP' bignum library: libgmp-dev
GNU MPFR library: libmpfr-dev

We recommend to compile Aleph-w with clang compiler. The Imakefiles are configured for using it, buy you can set another compiler such as gcc or icc.

If every dependency is correctly installed, then the following command sequence should build the library:

xmkmf
make depend
make libAleph.a

Examples

A lot of examples are located in Examples directory. They are demos intended to show the usage of a specific component of Aleph-w. They are not strictly maintained but their compilation is guaranteed on each master version. You are welcome to improve and eventually fix errors if you find them.

Only with debugging purposes, the examples use clang sanitizer. So, you should have clang installed or change the compiler by editing the Imakefile. In this case, you must remove the the -fsanitize=address,undefined compiler flag.

For building all the examples, execute:

xmkmf
make depend
make all

You could build a specific example:

make test-name

Tests

In order to execute the tests, which are optional and they are located in the Tests directory, you will need:

googletest https://github.com/google/googletest.
Ruby with the concurrent-ruby gem installed.
Version of llvm 6 or higher.
Ruby and the concurrent-ruby gem.

In order to execute the tests you must set two environment variables:

ALEPHW which must point to the directory where Aleph-w is.
GOOGLETEST which must point to the directory where googletest. The file gtest_main.a must be build which is expected to be found at the $GOOGLETEST/googletest/make/ directory.

The file test-list contains a list of each test. You can compile and execute each test by running all-test script.

In order to execute a specific test, you could use the run-test script. Some like as:

./run-test -f test-name

Use in projects

In order to use Aleph-w you simply must set your compiler for searching as include directory the site where Aleph-w is. Some times you could need to link libAleph.a.