similar to: Maximizing values in subsetted dataframe

Displaying 20 results from an estimated 4000 matches similar to: "Maximizing values in subsetted dataframe"

2009 Apr 24
1
deleting rows provisionally
I have an object. I think it is a matrix, called 'answer2' str(answer2) int [1:1537, 1:2] 1 399 653 2 3 600 4 5 271 870 ... - attr(*, "dimnames")=List of 2 ..$ : chr [1:1537] "a4.1" "hirschsprung.399" "peritoneal.653" "abdomen.2" ... ..$ : chr [1:2] "row" "col" I want to delete rows that have the same entries.
2006 Jan 18
22
Creating multiple child objects from the same form
I''ve been digging into rails, but this one question has been a two day stumper. I''ve got a question/answer model that I''m trying to work out. Each question has multiple answers (they''re more like choices, it doesn''t matter whether they''re right or wrong), and I''d like to have the question creation form also have multiple fields in
2006 Mar 18
2
extraction - subsets
Hi everybody, let us assume i have the following matrixX and vectorY matrixX <- runif(100) dim(matrixX) <- c(10,10) vectorY <- as.matrix(as.character(seq(1,10))) if I define: subsample<-c("2") i can extract the rows from matriX based on the elements in vectorY which are listed in subsample matrixX[vectorY==subsample] if I define subsample with more than 1 element, such
2006 Oct 12
9
Newbie question: 28000+ files for 25000+ records?
Hi Obviously my question is, is that normal? To have so many files? I was indexing 6 string fields from 25000+ model records (all of the same model). The index appears to be working. I guess I was expecting a few hundred files after optimzing, not more files that records indexed. Please understand I am brand spanking new to Lucene, Ferret, and AaF. I was using acts_as_ferret with :fields
2010 Apr 21
1
Best subset of models for glm.nb()
Dear List, I am looking for a function that will find the best subset of negative binomial models. I have a large data set with 15 variables that I am interested in. I want an easy way to run all possible models and find a subset of the "best" models that I can then look at in more detail. I have found two functions that seem to provide what I am looking for, but am not sure which
2011 Feb 04
1
Quadratic regression: estimating the maximizing value
A bioligist colleague sent me the following data. x Y 3 1 7 5 14 8 24 0 (Yes, only four data points.) I don't know much about the application, but apparently there are good empirical reasons to use a quadratic model. The goal is to find the X value which maximizes the response Y, and to find a confidence interval for this X value. Finding the maximizing X value is pretty
2009 Aug 13
3
Finding minimum of time subset
Dear List, I have a data frame of data taken every few seconds. I would like to subset the data to retain only the data taken on the quarter hour, and as close to the quarter hour as possible. So far I have figured out how to subset the data to the quarter hour, but not how to keep only the minimum time for each quarter hour. For example:
2009 May 26
2
Problem with fractional seconds
Dear List, I am having problems converting a file with fractional seconds to class POSIXct. I have set my options to include digits.secs and my format to just time, but my output is the current date with my time lacking the fractions of a second. For example: options(digits.secs=3) t<-c("06:00:00.100","06:00:01.231") myt<-as.POSIXct(t,format="%H:%M:%S")
2009 Sep 28
2
Data formatting for matplot
Dear List, I am wanting to produce a multiple line plot, and know I can do it with matplot but can't get my data in the format I need. I have a dataframe with three columns; individuals ID, x, and y. I have tried split() but it gives me a list of matrices, which is closer but not quite what I need. For example: id<-rep(seq(1,5,1),length.out=100) x<-rnorm(100,5,1)
2009 Oct 09
4
Satellite ocean color palette?
Dear List, Is there a color palette avaliable similar to what is used in satellite ocean color imagery? I.e. a gradient with blue on one end and red on the other, with yellow in the middle? I have tried topo.colors(n) but that comes out more yellow on the end. I am looking for something similar to what is found on the CoastWatch web page:
2002 Apr 22
3
no output from perl script
Here is the first Perl script I've tried to write to run rsync. It seems to work, but I don't see the progress like I should. I apologize if it's sloppy, I should add that it's not only the first perl script I've written for rsync, it's the first perl script I've written at all. ___________________________ #!/usr/bin/perl -w print " This command will DELETE
2008 Sep 16
1
analyze subsample of dataframe
Hi there, I'm dealing with a pretty big dataset (~22,000 entries) with numerous entries for every day over a period of several years. I have a column "judy" (for Julian Day) with 0 beginning on Jan. 1st of every new year (I want to compare tendencies between years). However, in order to control for a leap year (2004), I simply need to subtract 1 from every judy value for the year
2013 Jan 18
0
repeat resampling with different subsample sizes
Hi, I'm trying to write a code (see below) to randomly resample measurements of one variable (say here the variable "counts" in the data frame "dat") with different resampled subsample sizes. The code works fine for a single resampled subsample size (in the code below = 10). I then tried to generalize this by writing a function with a loop, where in each loop the function
2003 Feb 12
1
Na/NaN error in subsampling script
R-help readers, I''m having a problem with an R script (see below), which regularly generates the error message, Error in start:(start + (sample.length - 1)) : NA/NaN argument , for which I am unsure of the cause. In essence, the script (below) generates the start and end points for random subsamples from along a vector (in reality a transect (of a given length,
2009 May 26
4
Creating multiple graphs based on one variable
Dear List, I would like to create several graphs of similar data. I have x and y values for several different individuals (in this case fish). I would like to plot the x and y values for each fish separately. I can do it using a for loop, but I think I should be using "apply". Please let me know what I am doing wrong, or if there is a "better" way to do this. What I have
2009 Mar 21
1
Goodness of fit for negative binomial model
Dear r list,   I am using glm.nb in the MASS package to fit negative binomial models to data on manta ray abundance, and AICctab in the bbmle package to compare model IC.  However, I need to test for the goodness of fit of the full model, and have not been able to find a Pearson's Chi Squared statistic in any of the output.  Am I missing it somewhere?  Is there a way to run the test using
2009 May 21
2
help with gsub and date pattern
Dear List, I am having a problem using gsub to remove dates from a date/time string. For example: x<-c("5/31/2009 12:34:00","6/1/2009 1:14:00") I would like to remove the date and have just the time. I have tried: gsub("[0-9+]/[0-9+]/[0-9+]","",x) and various versions. I think my problem is that the / is a special character and is telling it
2007 Oct 28
1
maximizing a function
See http://mayin.nfshost.com/ajayshah/KB/R/documents/mle/mle.html -- Ajay Shah http://www.mayin.org/ajayshah ajayshah at mayin.org http://ajayshahblog.blogspot.com <*(:-? - wizard who doesn't know the answer.
2010 Feb 19
1
r help date format changes with c() vs. rbind()
Dear List, I am having a problem with dates and I would like to understand what is going on. Below is an example. I can produce a date/time using as.POSIXct, but I am trying to combine two as.POSIXct objects and keep getting strange results. I thought I was using the wrong origin, but according to structure(0,class="Date") I am not (see below). In my example a is a simple date/time
2006 Mar 01
3
Optimization problem: selecting independent rows to maximize the mean
Dear R community, I have a dataframe with 500,000 rows and 102 columns. The rows represent spatial polygons, some of which overlap others (i.e., not all rows are independent of each other). Given a particular row, the first column contains a unique "RowID". The second column contains the "Variable" of interest. The remaining 100 columns ("Overlap1" ...