need to convert list of dates to count no. of dates by week

[neowok]

Basically I have 2 columns each with a list of dates in no particular
order (and containing blank cells too), one planned date column and one
actual date column.

What I need to do is plot this on a graph, and since the number of
dates has no set limit and I dont want to have to plot maybe 100 dates
on the x axis, so i want to group them by week before plotting them,
i.e. 10 dates for week ending 10th jan, 25 dates for week ending 17th
jan etc

I have a pivot table that counts how many of each date occurs, i.e. 10
x 2nd jan, 7x 3rd jan etc etc but it does not split them into weeks.

im sure theres an easyish way of doing it so i can get the 2 lines on
the graph for no. of planned dates each week and no. of actual dates
each week, i just cant see it.

thanks

 

[Bob Phillips]

=SUMPRODUCT(--(A2:A200>=--"2006-01-04"),--(A2:A200<=--"2006-01-10"))

gives a count for the week in those dates

--

HTH

Bob Phillips

(remove nothere from the email address if mailing direct)

 

[neowok]

hmmm that would work if i have a smallish, set number of weeks and i
know what the weeks are, but this is a dynamic document where the date
range is subject to change daily

 

[Dave Peterson]

Is the date a row field?

How about rightclicking on it and choosing choose Group and show detail.

Then group by weeks.

If excel's weeks are different than yours, you could use add a new column in the
raw data and determine the week based on whatever rules you follow. Then use
that in the pivottable.

 

[neowok]

the dates are in 2 columns, i went to group but cant see how i could
group them by week (no options for this)

top few cells of one of the planned date column and 2 extra needed for
the graph may look something like this if it all works

Planned week ending numberof items
01-01-06 01-01-06 3
<blank cell> 08-01-06 2
<blank cell> 15-01-06 1
05-01-06 26-02-06 1
01-01-06
01-01-06
25-02-06
<blank cell>
<blank cell>
15-01-06
03-01-06
<blank cell>
etc etc

the graph could then be based on the week ending and number of items
column for the planned series, and then the same thing again for the
actual series.

I think i need to get an automated split of weeks in one column (B)
(ending on say sundays) and then in column C, the number of dates in
column A which falls during the week in column B

if not that then some other way of getting the same sort of result just
so I can draw the graph.

 

[Dave Peterson]

If your field has text or blanks, then you can't use that grouping.

Excel has a =weeknum() function that might be ok right out of the box.

=if(a2="","",weeknum(a2))
???

 

[neowok]

hm might be able to use severla more columns and use weeknum. i can use
a macro to copy the weeknum formula down for however many rows the
dates go, then maybe make a pivot table of that column giving me a
count of each weeknum, then somehow convert the weeknums into weeks
that i can use as x axis labels and base the chart off the pivottable
but without using a pivotchart. or something, but thats probly a bit
too complicated to work hehe ill have to fiddle with it on monday

 

[Dave Peterson]

Or instead of using the week number, use the date of the first day in the week
(or the Friday of that week or...)

 

[neowok]

hmmm i think that would work better. how would i get the date of th
friday in that week? because i would need those dates anyway as th
axis labels

 

[Bob Phillips]

=A1+(6-WEEKDAY(A1))

gets the Friday the date in A1

--

HTH

Bob Phillips

(remove nothere from the email address if mailing direct)

 

[neowok]

ok ive got 2 columns populated with planned dates and actual dates, al
converted to the friday of each week so i can get a count of how man
were planned/actual in a given week.

the major problem i have now is trying to plot the 2 series on the lin
graph. to get the counts of each date ive had to use 2 pivot tables
one that counts the dates in planned column and one counting the date
in the actual column.

2 problems with this are, i cant plot a graph from 2 different pivo
tables, and even if i could, the ranges of weeks do not match, i.e. th
2 pivot tables show

planned count actual count
6 jan 06 6 18 nov 05 24
20 jan 06 2 25 nov 05 13
27 jan 06 2 2 dec 05 37
3 feb 06 1 9 dec 05 12
16 dec 05 12
23 dec 05 10
20 jan 06 2

so as you can see, i somehow need to group up the dates from bot
planned and actual to use as the X axis catagories, and then plot the
series under the correct dates :confused

 

[Dave Peterson]

And depending on what should happen to the Saturday following that Friday:
=A1+6-MOD(A1,7)

 

[Dave Peterson]

I'm not sure if this fits, but if you made the planned/actual category a column
field in the pivottable, would it work ok?

 

[neowok]

thanks for replies.

i think i have a solution that works now using a few dummy columns wit
various formulas in to reduce it down to the required data for th
graph