Efficient code

GOTO 1 Efficient code even if frowned upon by programming purists... 

GoTo 1 Highly efficient code for a manual search even though frowned upon by purists... 

Despite the availability of fast computers and efficient codes for accurate quantum chemistry calculations, it is not likely in the near future that we will be able to study chemical reactions in proteins taking all the proteins atoms into quantum mechanical calculations. Hybrid methods in which different parts of large molecular systems are treated by different theoretical levels of methods are likely to play a key role in such studies for the coming decade or more. The ONIOM method we have developed is a versatile hybrid method that allows combining different quantum mechanical methods as well as molecular mechanics method in multiple layers, some features of... 

A number of efficient codes are available for the solution of MINLPs. These include the AlphaECP, BARON, DICOPT, MINLP, and SBB solvers descriptions of these can be found on the http //www.gamsworld.org/minlp/solvers.htm web site. 

Type The designer should know what types of object can be held in a variable—that is, the expected behavior of the object to which it refers. In Self and bare Smalltalk, this is left to the design documentation in C++, Java, and Eiffel, it is exphcit and some aspects are checked by the compiler. Explicit typing is allowed in some research variants of Smalltalk because it makes it possible to compile more-efficient code other compilers try to deduce types by analyzing the code. 

In the past decade more efficient code and faster computers have allowed the use of electron-correlated methods of calculation and this has opened this area of theoretical chemistry to a wide range of research groups. The present sequel will be focused mainly on recent theoretical studies on a variety of oxidative processes involving oxygen atom transfer. We will include an extensive description of the very recent chemistry of peroxyni-trous acid (HO—ONO), dioxiranes, peracids and alkyl hydroperoxides. Since chemically realistic molecular systems can now be treated at an adequate level of electron-correlated... 

The task facing a literate programmer extends beyond that of a computer programmer. The literate programmer must strive not only to create correct and efficient code, but also a description of the theoretical concepts that lie behind the code. 

Such movement of code should be performed by the designer to produce more efficient code this gives the logic optimizer a better starting point to begin optimizations. 

Another common programming model is the data parallel model. In this model the parallelism is extracted from the parallel operations that can be performed on arrays of data. Even though this programming model was first introduced on SIMD machines it is a misconception to believe it to be tied to these types of machines. The data parallel model is directly supported by HPF [29]. The model is clearly of great generality and very elegant, but not all parallel algorithms can easily be expressed in HPF and also compiled into efficient code. However, as compilers continue to improve this situation is sure to improve. 

CEPA and CPF have the advantage of structural simplicity. From a programming point of view, they differ only in minor details—which are easily implementedfrom CI(SD) procedures for which very efficient codes are available. Efficiency is an important aspect this is demonstrated by applications of CEPA and CPF which are routinely performed for relatively large systems (i.e. number of basis functions and orbitals correlated). 

For systems of point dipoles or higher multipoles the difficulties which must be overcome to realize efficient codes are similar to those encountered... 

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