Array question
in [Visual Basic]
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From: Alexandros Peropulous on 12 Aug 2010 05:13 Hello! I have documented my problem below. Can anybody help? Could it be done by CopyMemory? Private Sub Form_Load() Dim sngArr() As Single ReDim sngArr(1, 1) sngArr(0, 0) = -5 sngArr(0, 1) = -7 sngArr(1, 0) = -8 sngArr(1, 1) = -12 'Looks like this: ' -5 -7 ' -8 -12 Dim sngTest(1) As Single sngTest() = sngArr(1) 'I want to put -8 -12 into my sngTest array, but that's not working End Sub Thank you!
From: Mike S on 12 Aug 2010 06:26 On 8/12/2010 2:13 AM, Alexandros Peropulous wrote: > Hello! > > I have documented my problem below. > Can anybody help? Could it be done by CopyMemory? > > Private Sub Form_Load() > > Dim sngArr() As Single > ReDim sngArr(1, 1) > > sngArr(0, 0) = -5 > sngArr(0, 1) = -7 > > sngArr(1, 0) = -8 > sngArr(1, 1) = -12 > > 'Looks like this: > ' -5 -7 > ' -8 -12 > > Dim sngTest(1) As Single > sngTest() = sngArr(1) 'I want to put -8 -12 into my sngTest array, but > that's not working > > End Sub > > Thank you! Have you seen this yet? http://www.xtremevbtalk.com/archive/index.php/t-223190.html
From: Dee Earley on 12 Aug 2010 06:54 On 12/08/2010 10:13, Alexandros Peropulous wrote: > Hello! > > I have documented my problem below. > Can anybody help? Could it be done by CopyMemory? > > Private Sub Form_Load() > > Dim sngArr() As Single > ReDim sngArr(1, 1) > > sngArr(0, 0) = -5 > sngArr(0, 1) = -7 > > sngArr(1, 0) = -8 > sngArr(1, 1) = -12 > > 'Looks like this: > ' -5 -7 > ' -8 -12 > > Dim sngTest(1) As Single > sngTest() = sngArr(1) 'I want to put -8 -12 into my sngTest array, but > that's not working You can't do it via direct assignment. You MAY be able to do it with copymemory, but I can't remember which orientation the array is in memory. An alternative is to use an array of structures (Types) or an array of variants containing other arrays. This allows you to copy each main entry out of the main array as a whole. -- Dee Earley (dee.earley(a)icode.co.uk) i-Catcher Development Team iCode Systems (Replies direct to my email address will be ignored. Please reply to the group.)
From: dpb on 12 Aug 2010 09:50 Dee Earley wrote: > On 12/08/2010 10:13, Alexandros Peropulous wrote: >> Hello! >> >> I have documented my problem below. >> Can anybody help? Could it be done by CopyMemory? >> >> Private Sub Form_Load() >> >> Dim sngArr() As Single >> ReDim sngArr(1, 1) >> >> sngArr(0, 0) = -5 >> sngArr(0, 1) = -7 >> >> sngArr(1, 0) = -8 >> sngArr(1, 1) = -12 >> >> 'Looks like this: >> ' -5 -7 >> ' -8 -12 >> >> Dim sngTest(1) As Single >> sngTest() = sngArr(1) 'I want to put -8 -12 into my sngTest array, but >> that's not working > > You can't do it via direct assignment. > > You MAY be able to do it with copymemory, but I can't remember which > orientation the array is in memory. VB stores in column-major order. (So, the linear order of data in memor for sngArr is [-5 -8 -7 -12]) Hence the copy isn't contiguous elements. > An alternative is to use an array of structures (Types) or an array of > variants containing other arrays. Or, a language that supports array slices (such as Fortran or Matlab)... :) sngTest = sngArr(1,:) % Matlab syntax; Fortran is very similar --
From: Henning on 12 Aug 2010 11:02
"dpb" <none(a)non.net> skrev i meddelandet news:i40udv$v2e$1(a)news.eternal-september.org... > Dee Earley wrote: >> On 12/08/2010 10:13, Alexandros Peropulous wrote: >>> Hello! >>> >>> I have documented my problem below. >>> Can anybody help? Could it be done by CopyMemory? >>> >>> Private Sub Form_Load() >>> >>> Dim sngArr() As Single >>> ReDim sngArr(1, 1) >>> >>> sngArr(0, 0) = -5 >>> sngArr(0, 1) = -7 >>> >>> sngArr(1, 0) = -8 >>> sngArr(1, 1) = -12 >>> >>> 'Looks like this: >>> ' -5 -7 >>> ' -8 -12 >>> >>> Dim sngTest(1) As Single >>> sngTest() = sngArr(1) 'I want to put -8 -12 into my sngTest array, but >>> that's not working >> >> You can't do it via direct assignment. >> >> You MAY be able to do it with copymemory, but I can't remember which >> orientation the array is in memory. > > VB stores in column-major order. (So, the linear order of data in memor > for sngArr is [-5 -8 -7 -12]) > > Hence the copy isn't contiguous elements. > >> An alternative is to use an array of structures (Types) or an array of >> variants containing other arrays. > > Or, a language that supports array slices (such as Fortran or Matlab)... > :) > > sngTest = sngArr(1,:) % Matlab syntax; Fortran is very similar > > -- Or use the easy way out. sngTest(0) = sngArr(1,0) sngTest(1) = sngArr(1,1) If lots of elements. For i = 0 to NumElements sngTest(i) = sngArr(1,i) Next /Henning |