How to Print R Variables in Middle of String

How to print R variables in middle of String

The problem is that R does not evaluate any expression withing the quotes - it is just printing the string you defined. There are multiple ways around it. For example, you can use the sprintf function (untested because you do not provide a reproducible example):

   cat(sprintf("<set name=\"%s\" value=\"%f\" ></set>\n", df$timeStamp, df$Price))

R variable inside a string

variable2 <- paste0("I am argument:",variable1,"text continue")

Insert variable within character string

It seems this is what you are after.

for (i in 1 : length(file.list)) {
  file.name.variable <-  file.list[i]

  url <- paste0("https://accounts.profunds.com/etfdata/ByFund/", 
                   file.name.variable, "-historical_nav.csv")

  destfile <- paste0("C:/R Projects/Data/etf_aum/",
                          file.name.variable, "csv")

  download.file(url, destfile, mode="wb")
}

printing dates in the middle of a string in R

Try this:

paste0("http://www.stevel.com/log/?xid=2275644&dd=", Sys.Date() - 6:0)

giving this character vector:

[1] "http://www.stevel.com/log/?xid=2275644&dd=2015-01-15"
[2] "http://www.stevel.com/log/?xid=2275644&dd=2015-01-16"
[3] "http://www.stevel.com/log/?xid=2275644&dd=2015-01-17"
[4] "http://www.stevel.com/log/?xid=2275644&dd=2015-01-18"
[5] "http://www.stevel.com/log/?xid=2275644&dd=2015-01-19"
[6] "http://www.stevel.com/log/?xid=2275644&dd=2015-01-20"
[7] "http://www.stevel.com/log/?xid=2275644&dd=2015-01-21"

If you wanted to cat them out on 7 successive lines of the R console rather than output a character vector then if v is the character vector above then any of the following will do:

for(e in v) cat(e, "\n", sep = "")

cat(paste(paste0(v, "\n"), collapse = ""))

cat(paste(v, collapse = "\n"), "\n", sep = "")

or if its not a problem to have an extra space at the end of some lines then sep="" in the first and third above could be omitted. Alternately the gsubfn package has a cat0 function which is the same same as cat except the default sep is "".

In this case the loop seems substantially clearer than the non-loop solutions below it.

Print values for multiple variables on the same line from within a for-loop

Try out cat and sprintf in your for loop.

eg.

cat(sprintf("\"%f\" \"%f\"\n", df$r, df$interest))

See here

Format print statement

This will get you partway there:

x <- c(aa1,bb,cc)

options(useFancyQuotes = FALSE)
cat(paste(dQuote(x), collapse="   "), "\n")
# "abcdefghijklmnopqrstuvwxyz"   "10"   "222" 

I say "partway" because the code above doesn't take care of line-wrapping: if you hand it a very long vector of characters strings, they will all be cat'd to a single very long non-wrapping line...

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Edited to show one method of wrapping the lines:

You can get line-wrapping by using a combination of strwrap() (thanks @mnel) and gsub(), :

xs <- c(x,x,x,x)

cat(gsub("\" \"", "\"   \"", 
    strwrap(paste(dQuote(xs), collapse=" "), 70)), sep="\n")
# "abcdefghijklmnopqrstuvwxyz"   "10"   "222"   "abcdefghijklmnopqrstuvwxyz"
# "10"   "222"   "abcdefghijklmnopqrstuvwxyz"   "10"   "222"
# "abcdefghijklmnopqrstuvwxyz"   "10"   "222"

(The call to gsub() is needed if more than one space is needed between the vector elements, because strwrap() destroys whitespace in the input.)

Print raw string from variable? (not getting the answers)

I had a similar problem and stumbled upon this question, and know thanks to Nick Olson-Harris' answer that the solution lies with changing the string.

Two ways of solving it:

1. Get the path you want using native python functions, e.g.:

   test = os.getcwd() # In case the path in question is your current directory
   print(repr(test))
   

   This makes it platform independent and it now works with .encode. If this is an option for you, it's the more elegant solution.

2. If your string is not a path, define it in a way compatible with python strings, in this case by escaping your backslashes:

   test = 'C:\\Windows\\Users\\alexb\\'
   print(repr(test))
   

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