Sorting and searching
From OpenOffice.org Wiki
Neither OpenOffice.org Basic nor the API provide methods or functions for sorting arrays or searching within arrays.
It is quite common to sort almost sorted arrays, for example the list of style names belonging to a style family. Thus, I have found the shell sort to be the fastest for most uses in OpenOffice.org:
[oobas]
sub subShellSort(mArray)
dim n as integer, h as integer, i as integer, j as integer, t as string, Ub as integer, LB as integer Lb = lBound(mArray) Ub = uBound(mArray)
' compute largest increment n = Ub - Lb + 1 h = 1 if n > 14 then
do while h < n
h = 3 * h + 1
loop
h = h \ 3
h = h \ 3
end if do while h > 0 ' sort by insertion in increments of h
for i = Lb + h to Ub
t = mArray(i)
for j = i - h to Lb step -h
if strComp(mArray(j), t, 0) < 1 then exit for
mArray(j + h) = mArray(j)
next j
mArray(j + h) = t
next i
h = h \ 3
loop end sub Based on a routine available from [here].
Searching in a sorted list is compartively efficient with a binary search:
[oobas]
function fnBinarySearch(a, v)
nLeft = 0
nRight = uBound(a)
nLen = len(v)
while nLeft <= nRight
nMid = int((nLeft + nRight)/2)
if left(a(nMid), nLen) = v then
fnBinarySearch = nMid
exit function
elseif v < a(nMid) then
nRight = nMid - 1
else
nLeft = nMid + 1
end if
wend fnBinarySearch = -1 end function
