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diff --git a/doc/IGE335/Section2.01.tex b/doc/IGE335/Section2.01.tex new file mode 100644 index 0000000..d726634 --- /dev/null +++ b/doc/IGE335/Section2.01.tex @@ -0,0 +1,98 @@ +\subsection{Data organization}\label{sect:DataOrg} + +The structure of the input data is independent of the physical or computational +characteristics of the host system. The physical characteristics of the input +data is a collection of sequential records. These characters are by necessity +{\sc ascii} characters. The logical organization of an input deck is in the form +of a sequential structure of input variables presented in free format. This +structure must be located in the first 120 columns of each record in the input +stream. Characters located in column 121 and $\le$ 132 can be used to identify the +records and are treated as comments. An input variable can be defined in one of +two ways. + +\begin{itemize} + +\item As a set of consecutive characters containing no blanks; it will be +considered by DRAGON automatically as being an either an integer, a real or a +character variable depending on the format of the input variable. + +\item As a set of characters enclosed between quotation marks ({\tt '}). In +this case, the input variable is always considered to be a character variable. + +\end{itemize} + + +The only separator allowed between two input variables is a single or a set of +blanks (not enclosed between quotation marks). A single input variable cannot +span two records. Comments can be included in the input deck in one of the +following ways: + + +\begin{itemize} + +\item characters in column 121 and $\le$ 132 on each record are considered to be +comments; + +\item all the information following the `{\tt ;}' keyword on a record are not +considered by the generalized driver; + +\item each record starting with the characters `{\tt *}' is considered to be +commented out; + +\item all the characters on a given record inserted between `{\tt (*}' and `{\tt +'*)}' are considered to be commented out. + +\end{itemize} + + +This users guide was written using the following conventions: + +\begin{itemize} + +\item An input structure represents a set of input variables. It is identified +by a name in boldface surrounded by parenthesis. For example, the complete +DRAGON input deck is represented by the structure \dstr{DRAGON}; + +\item A standard DRAGON data structure represents a set records and directory +stored in a hierarchical format on a direct access +XSM file or in memory via a linked list.\cite{DragonDataStructures} It is +identified by a name in small capital letter. +For example, the data structure \dds{asmpij} contains the multigroup collision +probability matrices generated by the \moc{ASM:} module of DRAGON; + +\item The variables presented using the typewriter font are character +variables used as keywords. For example \moc{GEO:} is the keyword required to +activate the geometry reading module of DRAGON. + +\item The variables in italics are user defined variables. When indexed and +surrounded by parenthesis they denote arrays. If they are in lower case they +represent either integer type (starting with {\it i} to {\it n}) or real type +(starting with {\it a} to {\it h} or {\it o} to {\it z}) variables. If they are +in upper case they represent character type variables. For example, {\it iprint} +must be replaced in the input deck by an integer variable, ({\it +energy}(igroup), igroup=1,{\it ngroup}+1) states that a vector containing {\it +ngroup}+1 real elements is to be read while {\it FILE} must be replaced by a +character variable, its maximum size being generally specified. +No character variable can exceed 72 characters in length. + +\item The variables or structures surrounded by single square brackets `$[\;]$' +are optional. + +\item The variables or structures surrounded by double square brackets +`$[[\;]]$' are also optional. However, they can be repeated as many times +as required. + +\item The variables or structures surrounded by braces and separated by vertical +bars `$\{\; |\; |\; \}$' represents various calculation options available +in DRAGON. Only one of these options is permitted. + +\end{itemize} + +When a fixed default value is specified for an optional parameter in a +structure, it can be modified only locally and is reset to the original default +value each time the module is called. When a floating default value is specified +for a variable, it is saved and can be used in later calls to this module. In +DRAGON, almost every default value is a floating value, with the exception of +the parameter \dusa{iprint}, which is set to 1 and is used to control the amount +of information printed in the module. Departure from this general rule will be +indicated in the following sections. |
