Hi everyone,
I am hoping someone can help with my attempted use of the expression
function. I have a long series of text and variable to paste together
including a degree symbol. The text is to be placed on my scatter plot
using the mtext function.
Using expression like this:
changetext = expression(paste("Change from ",mini," to ",
maxi, ":",
diff ,degree,"C",collapse=""))
does not evaluate my user defined variables - mini,maxi, and diff -
just printing them out as words
Using expression like this:
changetext = paste("Change from ",mini," to ", maxi,
":", diff
,expression(degree,"C"),collapse="")
prints the text twice and does not evaluate the degree symbol.
I have tried to place the expression alone in a variable and then run the paste:
degsym = expression(degree,"C")
changetext = paste("Change from ",mini," to ", maxi,
":", diff
,degsym,collapse="")
giving me the same result as the second option
Is there any way I can use the expression function as in the first
example but still have R evaluate my user defined variables?
Thanks!
Sheri
Hi everyone,
I am hoping someone can help with my attempted use of the expression
function. I have a long series of text and variable to paste together
including a degree symbol. The text is to be placed on my scatter plot
using the mtext function.
Using expression like this:
changetext = expression(paste("Change from ",mini," to ",
maxi, ":",
diff ,degree,"C",collapse=""))
does not evaluate my user defined variables - mini,maxi, and diff -
just printing them out as words
Using expression like this:
changetext = paste("Change from ",mini," to ", maxi,
":", diff
,expression(degree,"C"),collapse="")
prints the text twice and does not evaluate the degree symbol.
I have tried to place the expression alone in a variable and then run the paste:
degsym = expression(degree,"C")
changetext = paste("Change from ",mini," to ", maxi,
":", diff
,degsym,collapse="")
giving me the same result as the second option
Is there any way I can use the expression function as in the first
example but still have R evaluate my user defined variables?
Thanks!
Sheri
---
Sheri O'Connor
M.Sc Candidate
Department of Biology
Lakehead University - Thunder Bay/Orillia
500 University Avenue
Orillia, ON L3V 0B9
On 10.10.2013 21:40, Sheri wrote:> Hi everyone, > > I am hoping someone can help with my attempted use of the expression > function. I have a long series of text and variable to paste together > including a degree symbol. The text is to be placed on my scatter plot > using the mtext function. > > Using expression like this: > > changetext = expression(paste("Change from ",mini," to ", maxi, ":", > diff ,degree,"C",collapse="")) > > does not evaluate my user defined variables - mini,maxi, and diff - > just printing them out as words > > Using expression like this: > > changetext = paste("Change from ",mini," to ", maxi, ":", diff > ,expression(degree,"C"),collapse="") > > prints the text twice and does not evaluate the degree symbol. > > I have tried to place the expression alone in a variable and then run the paste: > > degsym = expression(degree,"C") > changetext = paste("Change from ",mini," to ", maxi, ":", diff > ,degsym,collapse="") > > giving me the same result as the second option > > Is there any way I can use the expression function as in the first > example but still have R evaluate my user defined variables? > > Thanks! > SheriI'd rather use substitute for substitution of the symbols and get: plot(1, main = substitute("Change from " * mini * " to " * maxi * ": " * diff * degree * "C", list(mini=mini, maxi=maxi,diff=diff))) Best, Uwe Ligges