[libreoffice-users] [CALC] Automatic sheet generation

Hi,

This is my first message to that list, and I am a newbie with calc.

What I want to do is to extrapolate a sheet from an existing sheet, and
later do some calculation on the new sheet. The existing sheet is a
simple x/y graph with x on the A1, some values in A2 to An, and the
other rows, the value of x in the first cell, and the value of y for
the value corresponding to A2 to An in the following cells. This
give a chart with one x/y curve for each cell between A2 to An. This
work fine. The sheet look like:

x    -20     -10     0      10       20
0      0       0     0       0        0
1                                    0.1  
2                           0.2
3                  0.23
4            0.34                    0.15
5      0.4                  0.3
...

The new sheet will represent the values of x at A2 to An, that for
different values of y. In other words, the first sheet is y=f(x) for
different and constant n, the new sheet will be x=f(n) for different
and constant y.

n     0.1     0.2     0.3     0.4     0.5
20      1
10              2
0                       5
...

First I must have a way to search for the nearest 2 values of y in the
table, and from them do a calculation to extrapolate the value of x for
y. It must also know the value of n.

It is 2 cases, if the value of y = y_new sheet, no calculation is
needed, is the value of y != y_new sheet, I must make a simple
calculation to determine the value of x from the 2 nearest values of y.
(I have enough points, so I can assume it is a straight line between
the 2 values).

What I cannot figure out, is how to go trough the existing sheet with a
formula that will find the 2 nearest values of y and apply a function
on these values, or output directly the value if an exact match is
found. And from that build a new sheet.

Another issue is the original data comes from a csv file, that is
synchronized to the original sheet. The csv file is generated by
engauge, and between 2 runs, the numbers of rows and columns in that
file will change. That imply the new sheet must also be able to be
synchronized with the old one, and that even if the numbers of rows and
columns are changing. Is it possible to do that?


Can you explain me how to do this, or provide me a link to some
documentation describing a similar issue?

Cheers,
Dominique

-- 
To unsubscribe e-mail to: users+unsubscribe@global.libreoffice.org
Problems? http://www.libreoffice.org/get-help/mailing-lists/how-to-unsubscribe/
Posting guidelines + more: http://wiki.documentfoundation.org/Netiquette
List archive: http://listarchives.libreoffice.org/global/users/
All messages sent to this list will be publicly archived and cannot be deleted