What a lot of work when you can just krige the poygon directly! Try polygon kriging with my absolutely free, public domain, kriging game which works with any data set in a suitable format. This Windows based program provides he kriging equations and weights for the solution, so you can see how things work. Download from http://geoecosse.bizland.co/softwares along with tutorial data sets.
Isobel --- Pierre Goovaerts <[EMAIL PROTECTED]> wrote: > Dear Lorenz, > > The easiest way to proceed would be to discretize > your polygon > using a grid, use stochastic simulation to simulate > values within > the polygon, and estimate the block value as the > arithmetical average > of these simulated point values. > > The advantage is that you can empirically estimate > the variance of > your block estimate from the distribution of > simulated block values. > > It would be fairly easy to implement this procedure > using gslib > simulation routines. You just need to make sure that > only the > grid nodes within the boundaries of the polygon are > being simulated > (you can not just simulate a rectangular grid and a > posteriori > eliminate the values simulated outside the limits). > This requires > a "if statement" inside sgsim or sisim to skip any > grid node > falling outside the boundarie (just define a grid of > indicator values > that would be one if inside and zero if outside the > limits of > the polygon, and read this grid at the beginning of > the simulation). > > Best regards, > > Pierre > <><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><> > > Dr. Pierre Goovaerts > President of PGeostat, LLC > Chief Scientist with Biomedware Inc. > 710 Ridgemont Lane > Ann Arbor, Michigan, 48103-1535, U.S.A. > > E-mail: [EMAIL PROTECTED] > Phone: (734) 668-9900 > Fax: (734) 668-7788 > http://alumni.engin.umich.edu/~goovaert/ > > <><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><> > > On Fri, 20 Feb 2004, Lorenz Dobler wrote: > > > hello list, > > > > i would like to assign the principles of > block-kriging to user defined > > (=irregular) polygons. some questions about it: > > > > 1. what do you think about this idea ? > > 2. is there any software that can do this allready > ? > > 3. does anyone of you have practical experiences > with this approach ? > > 4. is there a realistic possibility to change > existing gslib libraries to do > > kriging with irregular polygons instead of regular > blocks (problem: finding > > center [of gravity] for each irregular polygon and > defining appropriate > > search neigbourhood !!) ? > > > > hope someone can help > > > > kind regards > > > > Lenz Dobler > > > > Universität Münster > > Institut für Geoinformatik > > Robert-Koch-Strasse 26-28 > > D-48149 Münster > > > > Tel.: 0251/83-30089 > > Fax: 0251/83-39763 > > email: [EMAIL PROTECTED] > > > > > > -- > > * To post a message to the list, send it to > [EMAIL PROTECTED] > > * As a general service to the users, please > remember to post a summary of any useful responses > to your questions. > > * To unsubscribe, send an email to > [EMAIL PROTECTED] with no subject and "unsubscribe > ai-geostats" followed by "end" on the next line in > the message body. DO NOT SEND Subscribe/Unsubscribe > requests to the list > > * Support to the list is provided at > http://www.ai-geostats.org > > > > > > > -- > * To post a message to the list, send it to > > * As a general service to the users, please remember > to post a summary of any useful responses to your > questions. > * To unsubscribe, send an email to [EMAIL PROTECTED] > with no subject and "unsubscribe ai-geostats" > followed by "end" on the next line in the message > body. DO NOT SEND Subscribe/Unsubscribe requests to > the list > * Support to the list is provided at http://www.ai-geostats.org ___________________________________________________________ Yahoo! Messenger - Communicate instantly..."Ping" your friends today! Download Messenger Now http://uk.messenger.yahoo.com/download/index.html -- * To post a message to the list, send it to [EMAIL PROTECTED] * As a general service to the users, please remember to post a summary of any useful responses to your questions. * To unsubscribe, send an email to [EMAIL PROTECTED] with no subject and "unsubscribe ai-geostats" followed by "end" on the next line in the message body. DO NOT SEND Subscribe/Unsubscribe requests to the list * Support to the list is provided at http://www.ai-geostats.org
