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Nick Hodge Nick Hodge is offline
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Default Pls confirm 2007 chart redraw is up to 10 times slower than 20

David

I was not defending the speed, far from it. The charting in this release
has undergone radical change and was not 'fully cooked' when a line had to
be drawn in the sand to release it. I suspect service packs will address
some major issues, but the real 'upgrade' will probably happen in v.next

Memory usage has gradually been improved over versions where more of the
'pool' can be used and 2007 is no different here. 2007 is also the first
version to allow multi-threaded calculations using multiple processors.

VLOOKUP does not have to be sorted if you need an exact match, just use
FALSE as the last parameter. This finds only an exact match, irrespective of
sort or returns #N/A

--
HTH
Nick Hodge
Microsoft MVP - Excel
Southampton, England
DTHIS
www.nickhodge.co.uk


"David Com" wrote in message
...
Nick,

I am only a hobby user, so I am sure there will be far more demanding
users
than me. I use Excel to research ideas for my hobby, and charts help me
visualise what is going on.

As an example, I have 27K rows, and about 30 columns of raw data. A macro
then creates another 30 rows. I may then sum various columns. I then
create a
new column with:

average (d2:d101)

and fill down the 27K rows, and display this single column as a chart.
Excel2007 is VERY slow. Excel 2000 does it fine, and much faster.
Obviously
the average calculation could be optimised, but I want a tool that is easy
to
use, without having to think too hard (and possibly make mistakes).

I believe I am using about 2 million cells, so if we assume 20bytes/cell,
that gives 40MB. That doesn't sound excessive.

If I open a chart (as above), it's slow to open in 2007. I can't right
click
the chart (or if I can the delay is about 20 secs). Sometimes (I don't
know
what I have done) I get a menu flash on the screen for about 1/2 sec, and
it's gone again. It's impossible to use! I would describe it as "Not fit
for
purpose".

I often like to delete sheets and move other sheets in to replace them.
Excel 2007 won't allow this. It allows the command but then complains that
the source (or is it destination) had too many rows or columns. WHY!

I accept your comment about databases. However Excel is good for a quick
experiment & chart. A database requires too much planning.

I have done a bit of reading in the last day, and have discovered that
Excel
2000 is only supposed to be able to have about 80MB of cells. My PC has
about
700MB, but Excel 2000 appeared to be using it all. Is this correct? (I
just
kept filling cells with 1, and then looked at the Task Manager). Excel
2007
seemed to have similar limits (just more rows, and less columns). Both
seemed
to allow about 33 milion cells.

Am I correct in assuming it is max row X max column which determines
memory
use?

There are some scenarios where Excel 2000 does really struggle, and I had
hoped 2007 would solve all my problems. I was hoping that with 1 million
rows/16K columns, it would need much better internal algorithms. From what
you are saying, it sounds like that wasn't possible. Is my best option to
simply buy more RAM and/or a faster PC? My experiments suggest Excel 2003
won't help me.

For my hobby, it's disappointing, but I'm sure I can find workarounds.
However, serious professional users may be rather more upset.

Most users have no idea how things like vlookup work, so they won't
understand when the performance is poor. However, I think Microsoft could
have helped themselves by adding an option which uses a sorted list, but
requires an exact match. It would be a simply tweak to the existing
algorithm, but allow users to use sorted lists more easily (I always want
exact matches. I know you can do it using two sorted vlookups, but it
should
not be necessary!)

David