search for: raghuraman

guRus! I have a function f = exp(x^2-y+(1/z)) Also, x can take values from 1 to 37, y from 2 to 20 and Z from -13 to 51. How can I find the maximum of f using any of the optimization functions please? Is there a way to store the possible values of x, y and Z in a single variable like in a List or in a multi-dimensional array? Thanks for your help Raghu [[alternative HTML version deleted]]

I''ve seen a number of posts where someone says, "What happens if you just run dispatch.fcgi directly?" Every time I do it, I get a "500: internal server error" message. I was just curious if that''s what''s expected running it directly. I assume so, because my apps all work fine, but that''s always bugged me. Pat

Hello I have a data frame like this: dput(states) structure(list(Date = c("24/07/2012", "25/07/2012", "26/07/2012", "27/07/2012", "28/07/2012", "24/07/2012", "25/07/2012", "26/07/2012", "27/07/2012", "28/07/2012"), State = c(1L, 1L, 1L, 1L, 1L, -1L, -1L, -1L, 1L, -1L)), .Names = c("Date",

Is there a option to make validates_uniqueness_of Case Sensitive, if so what is it, if not then how to do it without writing my own function. Regards Suraj

Dear R-Gurus I have a data frame (from CSV file) which has its first column called Date. The Date is in the format mm/dd/yyyy. I was trying to get the weekday for these dates and I tried using wday() and day.of.week() functions and both of them gave me precisely the wrong answers. I think the issue lies in the proper formatting of dates. The class of this column is a factor class and hence I

GuRus How do I use the write function (or write.table or write.csv) to achieve the following please? age=c(32,37,39) names=c("john","peter","jake") I would like create in a directory 3 files each named as john.csv,peter.csv and jake.csv and each file have data from the age vector. That is jon.csv will contain 32, peter.csv will contain 37 and jake.csv will contain

My Application runs fine when run on webrick, but throws up database error when run from apache. this is the copy of the FULL TRACE i get /usr/local/lib/ruby/site_ruby/1.8/oci8.rb:131:in `create'' /usr/local/lib/ruby/site_ruby/1.8/oci8.rb:131:in `initialize'' /usr/local/lib/ruby/gems/1.8/gems/activerecord-1.13.2/lib/active_record/connection_adapters/oci_adapter.rb:515:in

Hi I have say a large vector of 3500 digits. Initially the digits are 0s and 1s. I need to check for a rule to change some of the 0s to -1s in this vector. But once I change a 0 to -1 then I need to start applying the rule to change the next 0 only after I see the next 1 in the vector. Say for example x = (0,0,0,0,0,0,0,1,0,0,1,1,0,0,1,0,0,0,1) I need to traverse from the 9th element to the last

guRus I have say a dataframe, d and I wish to do the following: 1) For each row, I want to take one particular value of the row and multiply it by 2. How do I do it. Say the data frame is as below: OPEN HIGH LOW CLOSE 1931.2 1931.2 1931.2 1931.2 0 0 0 999.05 0 0 0 1052.5 0 0 0 987.8 0 0 0 925.6 0 0 0 866 0 0 0 1400.2 0 0 0 754.5 0 0 0 702.6 0 0 0 653.25 0 0 0 348 0 0 0 801 866.55 866.55

I have two files with dates and prices in each. The number of rows in each of them will differ. How do I create a new file which contains data from both these files? Cbind and merge are not helpful. For cbind because the rows are not the same replication occurs. Also if I have similar data how do I write a vlookup kind of function? I am giving an example below: Say Price1 file contains the

Is there a way by which i can associate a complex query with a Model class without using a VIEW, so that i can access all the names of the columns returned by the query.

Hi, I know that to make a dropdown box automatically submit when you change the value, you do this: <select ..... onchange="this.form.submit();"> BUT i''ve got an ajax form, and if i do the above trick, it simply reloads the ajax partial into the whole screen, rather than into the div where it is meant to go. I''ve already got it all working so that if you click

Hi I have a sorted array ( in ascending order) and I want to find the subscript of a number in the array which is the the next highest number to a given number. For example,if I have 67 as a given number and if I have a vector x=c(23,36,45,62,79,103,109), then how do I get the subscript 5 from x (to get 79 which is the next highest to 67) without using a for loop? Thx -- 'Raghu'

Hi all, I am using the Ganymed-SSH2 Java library to access openssh. I have enabled Keyboard Interactive authentication. After successfully returning the correct answer for the first challenge ( "[Password:]" ) the openssh server issues another challenge. The second time, the prompt is empty! The name, instruction are also empty. In addition the number of prompts variable is 0. I am not

Dear guRus Say I have a price vector, P which is P = c(20,50,40,50) for four consecutive days. My initial equity is say $100 and I re-invest the profits made in each transaction so my equity curve increases. If I go Long on day 1, short and short on day 2, long and long on day 3 and finally short on day 4, how do I calculate the total profits using R? Basically I stay invested at all times. I

Hi I wish to read a file from my local directory from inside a function. I am passing the filename as the argument but this does not work. Say for example function(dat) { dat1=read.csv("D:\\dat.csv",header=TRUE) } If I call funtion(dat) I get the following error. 'Intuitively' i understand this is a mistake but how do I overcome this and how can I read a file name passed as an

I know the following may sound too basic but I thought the mailing list is for the benefit of all levels of people. I ran a simple if statement on two numeric vectors (news1o and s2o) which are of equal length. I have done an str on both of them for your kind perusal below. I am trying to compare the numbers in both and initiate a new vector s as 1 or 0 depending on if the elements in the arrays

Hello I have a vector a =(-2,0,0,0,1,0,0,3,0,0,-4) I want to replace all zeros into previous non-zero state. So for instance the above vector should be converted into: a= (-2,-2,-2,-2,1,1,1,3,3,3,-4) I tried many things and finally concluded that probably(?) rollapply may be the best way? I tried f= function(x){ ifelse(x==0,Lag(x),x) } And then, rollappy(a,1,f) and that

When I just run a for loop it works. But if I am going to run a for loop every time for large vectors I might as well use C or any other language. The reason R is powerful is becasue it can handle large vectors without each element being manipulated? Please let me know where I am wrong. for(i in 1:length(news1o)){ + if(news1o[i]>s2o[i]) + s[i]<-1 + else + s[i]<--1 + } --

...ine of NAs (Peter Ehlers) > 34. Re: define stuff to be only usable in the same file > (Jessica Streicher) > 35. estimation of NA by predict command (eliza botto) > 36. Re: fill 0-row data.frame with 1 line of NAs (Brian Diggs) > 37. Help with vectors and rollapply (Raghuraman Ramachandran) > 38. Re: multiple comparisons with generalised least squares (Ariel) > 39. RGL 3D curvilinear shapes (PatGauthier) > 40. Re: estimation of NA by predict command (arun) > 41. Re: Count of elements in coulmns of a matrix (arun) > 42. Re: Help with vectors...