Free hexene molecular structure software for linux

Memory Structures Library (MemSL) is a complete data structures/collection classes library with memory tracing, memory debugging, entry/exit tracing, exception handling, definable memory handlers, built-in thread support, and much more.

The project supports single, double, and circular linked lists, AVL balanced and threaded binary trees, dynamic hashing tables, stacks, queues and dequeues (using arrays or linked lists), sets (Pascal implementation, with union, difference, intersection, etc.), bags, tables and dictionaries, priority heaps, priority search queue, and more.

Molecular Workbench project is a piece of free, open-source modeling software specifically designed for use in education. Powered by a set of real-time molecular simulation engines that compute and visualize the motion of particles interacting through force fields, in both 2D and 3D, it provides a simulation platform for teaching and learning science.
Many abstract concepts in physics, chemistry and biology can be dynamically visualized, and virtual experiments based on molecular simulations can be designed, limited only to your imagination.
The MW software consists of:
- a set of model builders, simulators and their associated scripting environments.
- a word processor for creating hypertext.
- an authoring system for constructing your own graphical user interfaces for your own simulations.
- an embedded-assessment system that allows you to design your own questions and collects student data.
- a special browser for you to deliver and for the users to access stuff created using the above sub-systems.
- Web services for collaboration among authors, students and teachers.
All these sub-systems are seamlessly integrated behind an easy-to-use graphical user interface. The customizability of models through the authoring system allows you to design user interfaces appropriate to your audience, without having to get them involved in the complexity of the modeling engines.

GNOME Structured File Library is a utility library for reading and writing structured file formats. Support for MS OLE2 streams is complete, as is zip import.
There is also support for document metadata and some initial work on decompressing VBA streams in OLE files for future conversion to other languages.
This library replaces libole2 and is used in gnumeric, mrproject, abiword, libwv2, koffice. It is also part of the AAF format.
Enhancements:
- This release reverts jump to dynamic types, as they arent thread-safe.
- A compilation glitch on Windows has been fixed.
- Problems building without gconf macros installed are avoided.
- Configure breakage with --without-gnome has been fixed.

GraphViz::Data::Structure can visualise data structures.

SYNOPSIS

use GraphViz::Data::Structure;

my $gvds = GraphViz:Data::Structure->new($data_structure);
print $gvds->graph()->as_png;

This module makes it easy to visualise data structures, even recursive or circular ones.
It is provided as an alternative to GraphViz::Data::Grapher. Differences:

GraphViz::Data::Structure handles structures of arbitrary depth and complexity, automatically following links using a standard graph traversal algorithm.
GraphViz::Data::Grapher creates graphics of indiividual substructures (arrays, scalars, hashes) which keep the substructure type and data together; GraphViz::Data::Structure does this by shape alone.
GraphViz::Data::Structure encapsulates object info (if any) directly into the node being used to represent the class.
GraphViz::Data::Grapher colors its graphs; GraphViz::Data::Structure doesnt by default.
GraphViz::Data:Structure can parse out globs and CODE references (almost as well as the debugger does).

Image::MetaData::JPEG::Structures is a Perl module that describes the structure of a JPEG file; it is an appendix to the main manual page of the Image::MetaData::JPEG module, which the reader should refer to for further details and the general scope.

THE STRUCTURE OF JPEG PICTURES

The JPEG (Joint Photographic Experts Group) ISO standard is a lossy image compression mechanism developed before 1990, designed for compressing colour or gray-scale photo-realistic images (it performs poorly on line-art drawings). The JPEG mechanism is designed to exploit known limitations of the human eye, in particular the fact that colour changes are perceived less accurately than changes in brightness.

Note that although the "baseline" JPEG format is patent-free, there are patents associated with some optional features, namely arithmetic coding and hierarchical storage. For this reason, these optional features are never used on the Web (good job, patent fans ...). JPEG refers only to a class of compression algorithms, not to a specific file format. In order to produce files with embedded JPEG streams, a number of file format (semi-)standards have been adapted or devised, some of which are listed in the format section. The structure of a well formed JPEG file can be described by the following pseudo production rules (for sake of simplicity, some additional constraints between tables and SOF segments are neglected).

JPEG --> (SOI)(misc)*(image)?(EOI)
(image) --> (hierarch.)|(non-hier.)
(hierarch.) --> (DHP)(frame)+
(frame) --> (misc)*(EXP)?(non-hier.)
(non-hier.) --> (SOF)(scan)+
(scan) --> (misc)*(SOS)(data)*(ECS)(DNL)?
(data) --> (ECS)(RST)
(misc) --> (DQT)|(DHT)|(DAC)|(DRI)|(COM)|(APP)

(SOI) = Start Of Image
(EOI) = End Of Image
(SOF) = Start Of Frame header (10 types)
(SOS) = Start Of Scan header
(ECS) = Entropy Coded Segment (row data, not a real segment)
(DNL) = Define Number of Lines segment
(DHP) = Define Hierarchical P??? segment
(EXP) = EXPansion segment
(RST) = ReSTart segment (8 types)
(DQT) = Define Quantisation Table
(DHT) = Define Huffman coding Table
(DAC) = Define Arithmetic coding Table
(DRI) = Define Restart Interval
(COM) = COMment segment
(APP) = APPlication segment

This package does not check that a JPEG file is really correct; it accepts a looser syntax, were segments and ECS blocks are just contiguous (basically, because it does not need to display the image!). All meta-data information is concentrated in the (COM*) and (APP) Segments, exception made for some records in the (SOF*) segment (e.g. image dimensions).

Reference: B< "Digital compression and coding of continuous-tone still
images: requirements and guidelines", CCITT recommend. T.81, 1992,
The International Telegraph and Telephone Consultative Committee,
standard ISO/IEC IS 10918-1 or ITU-T Recommendation T.81 >.
Also: B< "The JPEG still picture compression standard", G.K.Wallace,
1991, IEEE Transactions on Consumer Electronics >.

Struct::Compare is a recursive diff for perl structures.

SYNOPSIS

use Struct::Compare;
my $is_different = compare($ref1, $ref2);

Compares two values of any type and structure and returns true if they are the same. It does a deep comparison of the structures, so a hash of a hash of a whatever will be compared correctly.

This is especially useful for writing unit tests for your modules!

PUBLIC FUNCTIONS

$bool = compare($var1, $var2)

Recursively compares $var1 to $var2, returning false if either structure is different than the other at any point. If both are undefined, it returns true as well, because that is considered equal.

Ghemical is a computational chemistry software package released under the GNU GPL. It means that full source code of the package is available, and users are free to study and modify the package. Ghemical is written in C++.
Ghemical project has a graphical user interface (which is based on GNOME), and it supports both quantum-mechanics (semi-empirical and ab initio) models and molecular mechanics models (there is an experimental Tripos 5.2-like force field for organic molecules). Also a tool for reduced protein models [1] is included. Geometry optimization, molecular dynamics and a large set of visualization tools are currently available.
Ghemical relies on external code to provide the quantum-mechanical calculations. Semi-empirical methods MNDO, MINDO/3, AM1 and PM3 come from the MOPAC7 package (Public Domain), and are included in the source distribution.
The MPQC package (GNU GPL) is used to provide ab initio methods: the methods based on Hartree-Fock theory are currently supported with basis sets ranging from STO-3G to 6-31G**.
The MPQC code is not included in the source distribution. In order to use the MPQC-based ab initio methods in Ghemical, you must first compile and install the MPQC program for your system, and then compile Ghemical using some specific settings that link the programs together; see the INSTALL file for more information. Ghemical also contains the OpenBabel package for import and export of many different file formats (as well as other tasks).
Installation
Once you have downloaded the latest release, you should extract all files from your archive file using "tar -zxvvf ghemical-1.00.tgz" or equivalently "gunzip ghemical-1.00.tgz; tar -xvvf ghemical-1.00.tar". After that please read the "INSTALL"-file you just extracted to get additional information.
Enhancements:
- bug fixes