?"while"

You don't want a for loop. You need a while loop.

--------------------------------------

Jonathan P. Daily

Technician - USGS Leetown Science Center

11649 Leetown Road

Kearneysville WV, 25430

(304) 724-4480

"Is the room still a room when its empty? Does the room,

the thing itself have purpose? Or do we, what's the word... imbue it."

- Jubal Early, Firefly

[hidden email] wrote on 03/15/2011 10:14:21 AM:

> [image removed]

>

> [R] indeterminate for loop

>

> lm609

>

> to:

>

> r-help

>

> 03/15/2011 10:16 AM

>

> Sent by:

>

>

[hidden email]
>

> Hello,

>

> I have written a 'for' loop which on the first run makes nearest

neighbour

> calculations for my dataset 'A' in relation to dataset 'B', then based

on

> these results, some of the rows from A are moved into dataset B, and the

> calculation is repeated on the remaining rows in A. Therefore a smaller

and

> smaller amount of data is analysed as the loop proceeds, since A is

losing

> rows each time. The results of the calculation change as less data is

used,

> but not in a predictable way, therefore the end point of the loop is

> indeterminate.

>

> The script is long and the datasets big, but a simplified example where

'A'

> and 'B' are datasets, and the function 'ndist2' calculates 'x' is...

>

> for (i in 1:100)

> {

> C <- data.frame(ndist2(B,A))

> C1 <- subset(C, x = min(C$x))

> B <- rbind(B, C1)

> A <- subset(C, x > min(C$x))

> }

>

> So eventually A runs out.

>

> Currently, I let the loop run until a warning comes up which effectively

> says no more data, and at this point it is finished.

>

> What I would now like to do is place this loop inside another loop in

order

> to run through multiple datasets, but I can't do this when the script

> produces a warning message at the end of each dataset.

>

> Is there any way I can overcome this problem?

>

> Thanks for your help,

> Louise

>

> ______________________________________________

>

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>

https://stat.ethz.ch/mailman/listinfo/r-help> PLEASE do read the posting guide

http://www.R-project.org/posting-guide.html> and provide commented, minimal, self-contained, reproducible code.

______________________________________________

[hidden email] mailing list

https://stat.ethz.ch/mailman/listinfo/r-helpPLEASE do read the posting guide

http://www.R-project.org/posting-guide.htmland provide commented, minimal, self-contained, reproducible code.