Displaying 20 results from an estimated 10000 matches similar to: "Help with complicated regular expression"
2012 Oct 18
4
speeding read.table
R 2.15.1
OS X
Colleagues,
I am reading a 1 GB file into R using read.table. The file consists of 100 tables, each of which is headed by two lines of characters.
The first of these lines is:
TABLE NO. 1
The second is a list of column headers.
For example:
TABLE NO. 1
COL1 COL2 COL3 COL4 COL5 COL6 COL7 COL8 COL9 COL10
2018 Feb 13
3
Help with regular expressions
R 3.4.2
OS X
Colleagues
I would appreciate some help with regular expressions.
I have string that looks like:
" ITERATION ,THETA1 ,THETA2 ,THETA3 ,THETA4 ,THETA5 ,THETA6 ,THETA7 ,SIGMA(1,1) ,SIGMA(2,1) ,SIGMA(2,2)?
In the entries that
2012 Nov 28
3
Speeding reading of large file
R 2.15.1
OS X and Windows
Colleagues,
I have a file that looks that this:
TABLE NO. 1
PTID TIME AMT FORM PERIOD IPRED CWRES EVID CP PRED RES WRES
2.0010E+03 3.9375E-01 5.0000E+03 2.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 1.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00
2.0010E+03 8.9583E-01
2010 Feb 12
1
Identifying special characters in a text file
Colleagues
R 2.10.1 on a Mac
I read in textfiles using readLines, then I process those files, then I use R to execute another program. Occasionally those files contain characters other than letter / numbers / routine punctuation marks. For example, a bullet (option-8 on a Mac) triggers the problem.
Although R can read and process those characters, the other program cannot so I would like to
2011 Mar 29
2
Probing a function
R 2.12.2
Windows 7
Colleagues,
I just took advantage of the function:
readWindowsShortcut
in R.utils. It accomplished my goals and I was interested in learning its inner workings. So, I typed the function at the command line (without arguments or parentheses). R returned:
function (...)
UseMethod("readWindowsShortcut")
<environment: namespace:R.utils>
providing no
2018 Feb 13
0
Help with regular expressions
Hi Dennis,
How about:
# define the two values to search for
x<-2
y<-3
# create your search string and replacement string
repstring<-paste(x,y,sep=",")
newstring<-paste(x,y,sep=".")
# this is the string that you want to change
thetastring<-"SIGMA(2,3)"
sub(repstring,newstring,thetastring)
[1] "SIGMA(2.3)"
Use gsub if you want to change
2011 Apr 10
3
Adding margin text to lattice graphics
Colleagues
I am learning lattice graphics (R 2.12.2; OS X). Several days ago, I inquired about adding margin text to lattice graphics. Jim Price offered a useful reply, suggesting that I add:
page = function(page) grid.text('words', x = 0.5, y = 0.01)
to my call to the function. The entire function that he suggested was;
xyplot(1 ~ 1,
par.settings = list(layout.heights =
2023 Jan 16
3
Printing special characters
R 4.2.2
OS X
Colleagues
A file that I have read includes strings like this:
"EVENT ? 30 sec"
When I include the string in a graphic using:
mtext(STRING, ?)
it appears as:
"EVENT ... 30 sec"
Is there a simple work-around (short of reformatting all the strings, then using plotmath)?
Dennis
Dennis Fisher MD
P < (The "P Less Than" Company)
Phone / Fax:
2011 May 26
4
Applying "toupper" to only portions of text strings
Colleagues
Assume that I have a vector containing some text strings, some of which contain a particular character. I could like to apply "toupper" to the text before the character. For example (in this case, "|" is the particular character):
ORIGINAL:
TEXT <- c("aaaa", "bbb|cc", "|ddd")
AFTER APPLICATION OF toupper:
TEXT <-
2020 Oct 24
5
Package recommendations for outputting table with cell formatting
R 4.0.2
OS X
Colleagues
I have the unfortunate need to create a large number of tables (destined for a Word document). I need to color cells depending on the contents, e.g., blue if the value is < 0.5, red if the value is > 1.5.
If the output went initially to Excel, that would work; outputting directly to Word would be even better.
I expect that several packages can accomplish this. I
2011 Mar 25
2
Finding the common portion of strings
Colleagues
R: 2.12.2
OS X
I have a set of text objects in the form (I am showing 3 of what is more likely to be 20 or so):
OBJECTS <- c("abcSOMETHINGCOMMONegf", "xSOMETHINGCOMMONyz", "SOMETHINGCOMMONnme")
As you can see, all contain "SOMETHINGCOMMON" and the position varies. But, I don't know what that "SOMETHINGCOMMON" is.
Is there an
2009 Sep 23
2
Updating R for Linux
Colleagues,
Please forgive my ignorance of this topic. I am experienced with the
installation/use of R in OSX and Windows, much less so with Linux.
I just created a virtual machine of Ubuntu 9.0.4. Using the Synaptic
Package Manager, I installed R 2.8.1. I would like to obtain 2.9.x
and I am having trouble doing so using the tools available within
Ubuntu.
I tried
apt-get install
2018 Feb 22
2
Problem with geterrmessage()
Luke
Thanks ? I revised the code to:
ERRORMESSAGE <- try(source(USERSCRIPTFILE, local=T), silent=T)
print(ERRORMESSAGE) now returns:
$value
[1] 0
$visible
[1] FALSE
Not clear what to make of that.
Dennis
Dennis Fisher MD
P < (The "P Less Than" Company)
Phone / Fax: 1-866-PLessThan (1-866-753-7784)
www.PLessThan.com
> On Feb 22, 2018, at 12:45 PM, luke-tierney at
2005 Oct 18
6
Subsetting a list
Colleagues,
I have created a list in the following manner:
TEST <- list(c("A1", "A2"), c("B1", "B2"), c("C1", "C2"))
I now want to delete one element from the list, e.g., the third. The
command
TEST[[3]]
yields (as expected):
[1] "C1" "C2"
The command
TEST[[-3]]
yields:
Error:
2023 Mar 27
3
printing a data.frame without row numbers
R 4.2.3
OS X
Colleagues,
I am printing a large number of tables using the print command. A simple example is:
print(data.frame(COL1=1:5, COL2=10:6))
The result in this case is:
COL1 COL2
1 1 10
2 2 9
3 3 8
4 4 7
5 5 6
I would like to print the table WITHOUT the row numbers:
COL1 COL2
1 10
2 9
3 8
4 7
5 6
Is there any simple
2018 Feb 13
1
Help with regular expressions
You can either use positive lookahead/lookbehind - but support for that is a bit flaky. Or write a proper regex, and use
backreferences to keep what you need.
R > x <- "abc 1,1 ,1 1, x,y 2,3 "
R > gsub("(\\d),(\\d)", "\\1.\\2", x, perl = TRUE)
[1] "abc 1.1 ,1 1, x,y 2.3 "
B.
> On Feb 12, 2018, at 9:34 PM, Jim Lemon <drjimlemon at
2009 Sep 29
3
Deleting a column in a dataframe by name
Colleagues,
Hopefully a simple problem: I want to delete a column with a known
name from a dataframe. I could write:
FRAME <- FRAME[, names(FRAME) != NAMETODELETE]
or
FRAME <- FRAME[, !names(FRAME) %in% c(NAME1, NAME2, ETC)]
Is there some simpler means to accomplish this?
Dennis
Dennis Fisher MD
P < (The "P Less Than" Company)
Phone: 1-866-PLessThan (1-866-753-7784)
2008 Apr 11
3
strsplit and sapply
Colleagues,
I have some text:
TEXT <- c("a", "bb;ccc", "dddd;eeeee;ffffff")
I want to retrieve the portion of each element before the first
semicolon. I can split each element using strsplit:
SPLIT <- strsplit(TEXT, ";")
This yields:
> SPLIT
[[1]]
[1] "a"
[[2]]
[1] "bb" "ccc"
[[3]]
[1] "dddd"
2007 Sep 04
2
Recursive concatenation
Colleagues,
I want to create the following array:
"A1", "A2", "A3", "B1", "B2", "B3", "C1", "C2", "C3"
I recall that there is a trick using "c" or "paste" permitting me to
form all combinations of c("A", "B", "C") and 1:3. But, I can't
recall the
2009 Dec 04
3
Use of apply rather than a loop
Colleagues,
R 2.9.0 on all platforms
I have a dataset that contains three columns of interest: ID's, serial
elapsed times, and a marker. Representative data:
Subject Time Marker
1 100.5 0
1 101 0
1 102 1
1 103 0
1 105 0
For each subject, I would like to find the time associated with MARKER
== 1, then replace Time with Time - (Time[Marker == 1])
The result for this