Re: [R] Comparison of aggregate in R and group by in mysql

2008-01-26 Thread jim holtman
ui's suggestion and use a relational database system to handle the huge > data. > > > > > Date: Sat, 26 Jan 2008 20:40:51 -0500 > > > From: [EMAIL PROTECTED] > > To: [EMAIL PROTECTED] > > Subject: Re: [R] Comparison of aggregate in R and group by in mys

Re: [R] Comparison of aggregate in R and group by in mysql

2008-01-26 Thread zhihuali
40:51 -0500 > From: [EMAIL PROTECTED] > To: [EMAIL PROTECTED] > Subject: Re: [R] Comparison of aggregate in R and group by in mysql > CC: [EMAIL PROTECTED] > > I think with your data you will be computing a matrix that is 7049 x > 11704. This will require about 700MB of memor

Re: [R] Comparison of aggregate in R and group by in mysql

2008-01-26 Thread jim holtman
an)) > (I killed it after 30 minutes) > > > > > Date: Sat, 26 Jan 2008 19:55:51 -0500 > > From: [EMAIL PROTECTED] > > To: [EMAIL PROTECTED] > > Subject: Re: [R] Comparison of aggregate in R and group by in mysql > > CC: [EMAIL PROTECTED] > > > > >

Re: [R] Comparison of aggregate in R and group by in mysql

2008-01-26 Thread zhihuali
55:51 -0500 > From: [EMAIL PROTECTED] > To: [EMAIL PROTECTED] > Subject: Re: [R] Comparison of aggregate in R and group by in mysql > CC: [EMAIL PROTECTED] > > How large is your dataframe? How much memory do you have on your > system? Are you paging? Here is a test I ran wit

Re: [R] Comparison of aggregate in R and group by in mysql

2008-01-26 Thread jim holtman
How large is your dataframe? How much memory do you have on your system? Are you paging? Here is a test I ran with a data frame with 1,000,000 entries and it seems to be fast: > n <- 100 > x <- data.frame(A=sample(LETTERS,n,TRUE), B=sample(letters[1:4],n,TRUE), + C=sample(LETTERS[1:4],

Re: [R] Comparison of aggregate in R and group by in mysql

2008-01-26 Thread Gabor Grothendieck
How does the it compare if you read it into R and then do your aggregate with sqldf: library(sqldf) # example using builtin data set CO2 CO2agg <- sqldf("select Plant, Type, Treatment, avg(conc) from CO2 group by Plant, Type, Treatment") # or using your data: Xagg <- sqldf("select Group, Age, T

Re: [R] Comparison of aggregate in R and group by in mysql

2008-01-26 Thread Wensui Liu
huali, if i were you, i will create a view on the MySql server to aggregate the data first and then use R to pull the data through this created view. This is not only applicable to R but also a general guideline in similar situation. Per my understanding and experience, R is able to do data manipul