Reuse of iterator variables

IDFCNS-13
TitleDo not reuse iterator variables within a function.
PriorityStrongly recommended
DescriptionDo not reuse iterator variables within the same function. Limit the scope of an iterator variable to its for-loop. Prevents renaming all iterators when only the one for a specific loop must be renamed.
RationaleRobustness, readability

Avoid:

for iNode = 1 : numel(nodes)
    ...
end

for iNode = 1 : 2 : 11
    ...
end

Instead use:

for iNode = 1 : numel(nodes)
    ...
end

for iValue = 1 : 2 : 11
    ...
end