# construct the dataframe
`TK-QUADRANT` <- c(9161,9162,9163,9164,10152,10154,10161,10163)
LAT <-
c(55.07496,55.07496,55.02495,55.02496,54.97496,54.92495,54.97496,54.92496)
LON <-
c(8.37477,8.458109,8.37477,8.45811,8.291435,8.291437,8.374774,8.374774)
df <- data.frame(`TK-QUADRANT`=`TK-QUADRANT`,LAT=LAT,LON=LON)
# group the data and calculate means by group
df$group <- floor(df$TK.QUADRANT/10)*10
out <- aggregate(df[c('LAT','LON')],by=list(df$group),mean)
print(out)
# see also:
#
https://livefreeordichotomize.com/2018/06/27/bringing-the-family-together-finding-the-center-of-geographic-points-in-r/
Rgds,
Robert
On 14/11/2018 11:13, sasa kosanic wrote:
?Dear Robert,
Thank? you for your very much for your reply. Please see attached pdf?
fille.
I hope now it is more clear what I am trying to do:
calculate new latitude and? longitude? of the centroids from the
existing cells...
as you can see from the attached pdf.? from Lat/ Long of
9161,9162,9163,9164 I need to calculate a single Lat/Long that could
be fore example called 9160
and then from lat/ long of 10152 and 10154 a? new single lat/long
called 10150 .
But guess I would need some kind of loop as this is just an example
table? and the the whole table is covering whole Germany.
Please let me know if it is still not clear what I am trying to do here.
Best wishes,
Sasha
On Wed, 14 Nov 2018 at 07:58, Robert David Burbidge
<robertburbidgedata at yahoo.co.uk
<mailto:robertburbidgedata at yahoo.co.uk>> wrote:
Hi Sasha,
Your attached table did not come through, please see the posting
guidelines:
"No binary attachments except for PS, PDF, and some image and archive
formats (others are automatically stripped off because they can
contain
malicious software). Files in other formats and larger ones should
rather be put on the web and have only their URLs posted. This way a
reader has the option to download them or not."
https://www.r-project.org/posting-guide.html It is not clear what you are trying to do. As a first step it looks like you want something like: ?>>>>>>>>>>>>>>>> lat <- c(9161,9162,9163,9164,10152,10154) floor(lat/10)*10 <<<<<<<<<<<<<<<< Please provide further details on what you are trying to do. Rgds, Robert On 13/11/2018 09:51, sasa kosanic wrote: > Dear All, I am pretty new to R and would appreciate a help how to > calculate centroids from the latitude and longitude of existing cells > (e.g. to get centroid for a new cell I would need to combine latitude > and 9161,9162,9163,9164 to 9160 or 10152, 10154 to 10150 etc.) Please > see attached table. Thank you very much! Best, Sasha -- Dr Sasha Kosanic Ecology Lab (Biology Department) Room M644 University of Konstanz Universit?tsstra?e 10 D-78464 Konstanz Phone: +49 7531 883321 & +49 (0)175 9172503 http://cms.uni-konstanz.de/vkleunen/ https://tinyurl.com/y8u5wyoj https://tinyurl.com/cgec6tu