similar to: User R to create MySQL database and table

Dear colleague, I have two data frame which I tried to use dbWriteTable function with append=TRUE to write to the mysql database. The problem is that if I am run my R script directly then it is fine. Both data frame got written into the database. But when I tried to embed the script to be called as system("R --save < whatever.R") in my perl script, I saw very strange things. One

Hi, In perl, to get a substring matching a particular pattern can be implemented like the following example: $x = "AAAA.txt"; if ($x=~ /(.*?)\.txt/){ $prefix = $1; } So how to do the same thing in R? Can someone provide me the code sample? Thanks much in advance. -- Waverley @ Palo Alto

Hi, Can someone help as how to use R to program google search in the R code? I know that other languages can allow or have the google search API If someone can give me some links or sample code I would greatly appreciate. Thanks. -- Waverley @ Palo Alto

I use ROCR to plot multiple runs' performance. Using the sample code as example: # plot ROC curves for several cross-validation runs (dotted # in grey), overlaid by the vertical average curve and boxplots # showing the vertical spread around the average. data(ROCR.xval) pred <- prediction(ROCR.xval$predictions, ROCR.xval$labels) perf <- performance(pred,"tpr","fpr")

Hi, I am trying to write a RMySQL sql script inside R such that part of the SQL would be R list or vector. For example, I want to select * from Atable where ID would equal to a members of R list or vector of "1, 2, 3". Here the ID list was generated inside R and then try to feed to mysql to call to get additional data sets. Can someone on the list help? Thanks. -- Waverley @ Palo

Dear Colleagues, I am looking for a package or previous implemented R to subgroup and exaustively divide a vector of squence into 2 groups. For example: 1, 2, 3, 4 I want to have a group of 1, (2,3,4) (1,2), (3,4) (1,3), (2,4) (1,4), (2,3) (1,2,3), 4 (2,3), (1,4) ... Can someone help me as how to implement this? I get some imaginary problem when the sequence becomes large. Thanks much in

Hi, I have a matrix a = matrix (1:16, 4, 4) b = c (2,3) I want to find out which rows of a, where a[,1] equals any values of b? I know that if b is only one value, e.g, b=2, then what I want is a[a[,1] == 2,] But what about if it is not one value but a vector of values? Thanks much in advance. -- Waverley @ Palo Alto

Hi, I have a question of aov. e.g. aov.ex = aov(x~y) summary(aov.ex) The aov summary will print to the screen. How can I extract the aov result, in particular the values of Pr(>F) and F value into a vector so that I can use them for other use? Thanks. -- Waverley @ Palo Alto

Hi, I am using the function heatmap(stats) to draw a microarray heatmap, columns are samples and rows are gene features. I did a 2D clustering during the heatmap drawing. The features and samples indeed cluster into several blocks both vertically and horizontally. I can get the index of re-ordered rows and columns after the heatmap drawing by typing the the return variable of the heatmap

Hi, I have a question about ROCR package. I got the ROC curve plotted without any problem following the manual. However, I don't know to extract the values, e.g. y.values ( I think it is the area under the curve auc measure). The return is an object of class "performance" which have Slots and one of the slot is "y.values". I type the object and I can see them in

Hi, I understand for 1 d classifiers, you can use ROCR package. Is there a package you can plot ROC curve for 2d classifiers? One of my colleagues asked me about this. I have been quite puzzled, conceptually, how you can do the ROC curve for 2d classifiers. Can someone share his/her knowledge or experience? Thanks in advance. -- Waverley @ Palo Alto

Hi, I want to extract some of the substring via pattern recognition. But I don't know how to do it in R. In perl: my $url = "/pages-cell.net/deepan/sony/"; if($url =~ m/\/(.*)\//g) { my @result = $1; return @result; } How does the same work in R? Thanks much in advance -- Waverley @ Palo Alto

Hi, I tried to use boxplot function. I am following the ?boxplot and can change the whisker box width using lwd parameter. However, when outline=TRUE, the thickness of the circle of the outliers is not proportionally changed when I change the line width of the whisker box. There must be another parameter for that. Unfortunately I don't know. please help and thanks much in advance. --

Hi, I have one matrix derived from my function. It is as following: Browse[1]> each.uaa.data [,1] [,2] [1,] 33 152.3530 [2,] 33 264.7059 [3,] 51 583.3333 [4,] 33 323.3333 [5,] 50 292.549 [6,] 33 300 [7,] 56 104.1176 [8,] 52 246.6667 [9,] 53 242.5490 [10,] 33 212.9412 when I tried to get each.uaa.data[,2], it gave me a list, when I expect a vector so that

Hi, I have a question in regarding to how to perform power analysis and sample size estimation/projection using R? I know power.t.test. It works really well with only one feature analysis. I have a set of features which collectively can discriminate binary classes. I can do power.t.test for each one feature to get a distribution for the sample size estimation to achieve certain power and

Hi, when I assign a one row matrix to another variable, then somehow R automatically convert that varaible into a list. For example: > a = matrix (12, 3, 4) > b = a[1,] > b [1] 12 12 12 12 Is there a way to enable R automatically make b as a one row matrix , rather than explicitly assign like matrix (b, ncol=1). I have come across a couple of time, that when I try to check how many

Please help. I found the code in the archive. The author of this script says: "The first function (seROC) calculate the standard error of ROC curve, the second function (cROC) compare ROC curves." Can some one explain to me what are the na, nn and r parameters which are used as the input to the following two functions? Thanks much in advance. > From: Bernardo Rangel Tura >

Hi all, This is the data: > dput(head(dt1,20))structure(list(StationName = c("PALO ALTO CA / CAMBRIDGE #1", "PALO ALTO CA / CAMBRIDGE #1", "PALO ALTO CA / CAMBRIDGE #1", "PALO ALTO CA / CAMBRIDGE #1", "PALO ALTO CA / CAMBRIDGE #1", "PALO ALTO CA / CAMBRIDGE #1", "PALO ALTO CA / CAMBRIDGE #1", "PALO ALTO CA / CAMBRIDGE

?s 01:49 de 03/11/2023, roslinazairimah zakaria escreveu: > Hi all, > > This is the data: > >> dput(head(dt1,20))structure(list(StationName = c("PALO ALTO CA / CAMBRIDGE #1", > "PALO ALTO CA / CAMBRIDGE #1", "PALO ALTO CA / CAMBRIDGE #1", > "PALO ALTO CA / CAMBRIDGE #1", "PALO ALTO CA / CAMBRIDGE #1", > "PALO ALTO

Is this what you are after? library(tidyverse) library(lubridate) input <- structure(list(StationName = c("PALO ALTO CA / CAMBRIDGE #1", "PALO ALTO CA / CAMBRIDGE #1", "PALO ALTO CA / CAMBRIDGE #1", "PALO ALTO CA / CAMBRIDGE #1", "PALO ALTO CA / CAMBRIDGE #1", "PALO ALTO CA / CAMBRIDGE #1", "PALO ALTO CA / CAMBRIDGE