Hi,
If we need to allow for special (i.e. irregular) grid or tick
placements, I think we we need to add to the suite of
chart:interval-major attributes. In we had a
chart:axis-type="date" kind of axis we would need to define the
interaction with these attributes anyway.
Even in the presence of chart:axis-type="date" we would need
additional tick placement attributes since one can as well argue
for ticks at the mid-month position as at the first of the month
position.
Andreas
On 17-10-14 07:09 AM, Regina Henschel
wrote:
Hi Andreas,
shouldn't this go to ?
An essential additional feature of a "date"-scale is, that it
allows a major grid in month, so that each grid line can be on the
1st of the month, independent of the length of the month. Thereby
still each month has its own amount of days.
Kind regards
Regina
Andreas J. Guelzow schrieb:
Hi,
I think I finally understand the problem chart:axis-type="date"
is
suppsed to address:
Some charts, for example the chart:bar class, have an axis that
is
predefined to be either a categories axis (i.e. category labels
are
evenly spaced and the corresponding values are shown at these
evenly
spaced locations) or a value axis (i.e. values are shown at
their
relative locations).
For example for a barchart with x-values that are dates (years
), e.g.
1950,1980, 2000, 2010, with a category type axis the 4 bars
would be
evenly spaced as if at values 1,2,3,4 with these points on the x
axis
labelled 1950,1980, 2000, 2010. If we had the same chart type
but with a
value type x-axis the bars would not be evenly spaced since the
difference between 1950 and 1980 will be three times as large as
the
difference between 2000 and 2010.
I believe Regina's suggestion is to obtain the second chart by
labelling
flagging the second axis as chart:axis-type="date".
To me all of this has nothing to do with dates. These values
1950,1980,
2000, 2010 simply differ from other categories like a,b,3,d that
they
are all numbers and so can be interpreted as relative locations
on the
x-axis.
So since there is nothing special about dates being involved
(except
that apparently Excel allows the second type of chart only for
date
values) I believe we should not make this date specific, but
simply flag
axis with their type (if it differs from their default type),
e.g.
chart:axis-type="values" or chart:axis-type="categories" or
chart:axis-type="value-preference" where the last type means
that if all
values/categories given are numbers then the axis behaves like a
value
axes (placing items in their relative position) and like a
categories
axis otherwise.
Andreas
--
Andreas J. Guelzow, PhD FTICA
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Registrar & Director of Enrolment Services
Professor of Mathematical & Computing Sciences
Direct: +1 780 479 9290
Toll-Free: +1 866 479 5200
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--
Andreas J. Guelzow,
PhD FTICA
Registrar
& Director of Enrolment Services
Professor
of Mathematical & Computing
Sciences
Direct:
+1 780 479 9290
Toll-Free: +1 866 479 5200
concordia.ab.ca
