[R] Reading a large csv file row by row

appreciated! Best Wishes Yuchen Luo [[alternative HTML version deleted]] __ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide

Re: [R] Reading a csv file row by row

Hi, my friends. When a data file is large, loading the whole file into the memory all together is not feasible. A feasible way is to read one row, process it, store the result, and read the next row. In Fortran, by default, the 'read' command reads one line of a file, which is convenient, and

[R] How to manipulate the pointer of a file?

: $name [1] Tom $wife [1] Joy $no.kids [1] 9 -- My question is, how to manipulate the pointer of the file further? For example, what if I need the pointer to go back to the previous row? Best Wishes Yuchen Luo [[alternative HTML version deleted

[R] How to lower the 'miniFactor' when using nls( ) function?

' the only solution to the problem? What are the other options? Best Wishes Yuchen Luo [[alternative HTML version deleted]] __ [EMAIL PROTECTED] mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http

[R] nls.control( ) has no influence on nls( ) !

see is a separate command like 2). A more relevent question might be, is lower the 'minFactor' the only solution to the problem? What are the other options? Best Wishes Yuchen Luo [[alternative HTML version deleted]] __ R-help@stat.math.ethz.ch

[R] if within a function

Dear Friends. I found a puzzling phenomenon in R when you use 'if' within a function: # defining a function aaa aaa=function(a) {if (a==1) {aaa=1}; if (a!=1) {aaa=2} } # using the function: b=20 bbb=aaa(b) bbb [1] 2 typeof(bbb) [1] double c=1 ccc=aaa(c) ccc NULL typeof(ccc) [1] NULL

[R] set up a talbe with column name and write to the table row by row

Dear Friends. I tried to set up a table with column name and write to it row by row. I have 3 rows to write to the table: a1 - list(name=Fred, wife=Mary, no.children=3) a2 - list(name=Tom, wife=Joy, no.children=9) a3 - list(name=Paul, wife=Alic, no.children=5) When I write to it, the first

[R] Setting up a blank table with column names in the hard drive

front. How ever, I do not have the first loop of the program completed yet at that time. If I add a row that is meaningless, how may I delete it after all the loops are completed and all the meaningful rows are added to the table? Best Wishes Yuchen Luo [[alternative HTML version deleted

[R] Looping through a series of (csv) files

Wishes Yuchen Luo [[alternative HTML version deleted]] __ R-help@stat.math.ethz.ch mailing list 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

[R] Saving an expression to a file

the expression to a file? Best Wishes Yuchen Luo [[alternative HTML version deleted]] __ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html

[R] set up a blank csv file and write time series to it row by row

' but I do not know how many of them are going to come up. Examples are : bb1=c(1:10) bb2=c(101:110) How to write bb1 and bb2 to a csv file and how to set up blank csv file to accept such time series in the first place? Your help will be highly appreciated!!! Best Wishes! Yuchen Luo

[R] How to store the parameter estimated by nls( ) to a variable?

in every loop of my code and I need to store the estimated values for further use. I have checked both the online manual and several S-plus books but no example as such showed up. Your help will be highly appreciated! Best Wishes Yuchen Luo [[alternative HTML version deleted

Re: [R] How to store the parameter estimated by nls( ) to a variable?

Dear Professor Murdoch. Thank you so much Best Wishes Yuchen Luo On 8/12/07, Duncan Murdoch [EMAIL PROTECTED] wrote: Yuchen Luo wrote: Dear Colleagues. I believe this should be a problem encountered by many: nls( ) is a very useful and efficient function to use if we are just

[R] How to write to a table column by column?

other and I can easily compare their elements. ( If I use 'appened=TRUE', the second time series will be stored in the same column. ) Thank you for your tine and your help will be highly appreciated!! Best Yuchen Luo [[alternative HTML version deleted

[R] How to let the program know the end of a file is reached?

Dear collegues. I am using scan( ) to read from a table (a csv file). I am wondering how to let the program know that the end of the file is reached? Your help will be highly appreciated! Best Wishes Yuchen Luo [[alternative HTML version deleted

[R] How to signal the end of the table?

to articulate while (the end of the table has not been reached), or equivalently, how to signal the end of the table? Best Wishes Yuchen Luo [[alternative HTML version deleted]] __ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman

[R] 'singular gradient matrix’ when using nl s() and how to make the program skip nls( ) and run on

into a problem. I would still need the program to run the remaining 217 nls( )! Is there a way to make the program skip the problematic nls() and complete the ramaining nls()'s? Your help will be highly appreciated! Yuchen Luo [[alternative HTML version deleted

[R] 'initial value not feasible' in constrOptim

a fortran code to R and the function I want to replace is DBCPOL, which used 'the complex method described in Nelder and Mead (1965) and Gill et al. (1981). I believe contrOptim is better than it because it is newer, is it? Best Wishes Yuchen Luo [[alternative HTML version deleted

[R] What does it mean by initial value not available?

of the objective function is not well defined at the point of the initial value. 3. The initial value violate the constrain of ui %*% theta - ci = 0 But my situation does not belong to any of the above cases. I have attached my code bellow and could you please help me take a look? Best Wishes Yuchen Luo rm

Re: [R] What does it mean by initial value not available?

and 4th line) Please correct them as: sigmae=c(0.172239074,0.188209271,0.193703774,0.172659891,0.164427247,0.24602361,0.173555309,0.186701165,0.193150456, 0.1857315601) ss=c(56.49,56.39,56.55,57.49 ,57.37,55.02,56.02,54.35,54.09,54.67) Best Wishes Yuchen Luo On 9/9/07, Duncan Murdoch [EMAIL

[R] Are the error messages of ConstrOptim() consisten with each other?

=fit.error.grr, ui=ui,ci=ci) Error in f(theta, ...) : argument lambda1 is missing, with no default I only changed the parameters, how come the lambda1 that is not missing in the first 2 cases suddently become missing? For your convenience, I put the complete code below: Best Wishes Yuchen Luo

Re: [R] Are the error messages of ConstrOptim() consisten with each other?

(0.5,0.3,0.5)) cannot violate both ui%*%theta=ci and -ui%*%theta=-ci. 2. There is lambda1 available. The 0.3 in c(0.5,0.3,0.5) is lambda1. If you plug c(0.5,0.3,0.5) into fit.error and fit.error.grr by fit.error(0.5,0.3,0.5) fit.error.grr(0.5,0.3,0.5) It works. Best Wishes Yuchen Luo On 9/10/07