2.3.4 Structure Element: Loop

The Loop element indicates that the contained structure and/or operations should be repeated a certain number of times. Loop elements can be nested in order to populate a multi-dimensional array. Loops can be set up in four different ways, which can be combined as needed:

• fixed length
• read the number of elements that was previously specified in the file (see Example 1 below, with NWAVES)
• read until a stop value is encountered (see Example 2 below)
• read until an end-of-file is encountered (see Example 2 below).

The Loop element has the following attributes:

Attribute Name	Description	Required
loopVariable	Name of a local variable that stores the value of the loop index (iteration)	no
start	The starting value for the loop index. This can be an integer or the name of a parameter whose value had been set previously	yes
end	The ending value for the loop index. This can be an integer or the name of a parameter whose value had been set previously	yes
incr	The increment value for the loop index. This can be an integer or the name of a parameter whose value had been set previously	yes
check	Value to be checked as part of the stop condition	no
operator	The relational operator to be used. Must be GT (greater than), LT (less than), or EQ (equal to)	no
checkValue	The value to check against. This can be the name of a parameter whose value has been set previously	no
stopOnEof	True/False. If an end-of-file is encountered, a value of ``True'' will throw an exception but the method returns normally; set to ``True'' if an EOF is expected	no
doOnce	True/False. ``True'' means that, even if the checkValue fails, execute the loop once	no

The Loop element must contain one or more structure elements such as Condition or another Loop, or one or more operation elements such as Separator, SetValue, SetSize, SetDims, or AddValue in any order.

$\parbox{6.3in}{\textcolor{blue} {\textbf{Example 1 \hrulefill}}\\ \... ...before reading the values of WSCSTP and WSCFAC \\ \textcolor{blue}{\hrulefill}}$

$\parbox{6.3in}{\textcolor{blue} {\textbf{Example 2 \hrulefill}}\\ \... ...hese operator conditions is met, the Loop ends \\ \textcolor{blue}{\hrulefill}}$

Another example, with a portion of an input file, is given in Section 3.3.