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Formatting numbers for display

6 messages · Dennis Fisher, arun, David Winsemius +2 more

Dennis Fisher
# 
Colleagues

R 2.15.1
OS X

I have a lengthy script that generates a positive number that I display in a graphic using text.  The range of possible values is quite large and I am looking for an efficient means to format.  
	1.  If the number is large (e.g., > 10^7), I want to display only the integer portion.
	2.  If it is less than 10^7 but > 1, I want to display 8 characters, e.g., 
		12345.78
		1234.678
		123.5678
	3.  If it is less than 1, I want to display at least three significant digits, e.g.
		0.123
		0.0123
		0.00123
		0.000123
If there are any inconsistencies in my proposal, I apologize.

I can accomplish this by brute force with conditionals, -ceiling(log10(VALUE)), round.  However, I expect that there is a more efficient approach, possibly using sprint.

For the "dput"-ers, use the following as potential input:
VALUES	<- c(123456789, 12345678, 1234567.9, 123456.89, 12345.789, 1234.6789, 123.56789, 12.456789, 1.3456789, 0.123456789, 0.0123456789, 0.00123456789)

Thanks for any thoughts.

Dennis

Dennis Fisher MD
P < (The "P Less Than" Company)
Phone: 1-866-PLessThan (1-866-753-7784)
Fax: 1-866-PLessThan (1-866-753-7784)
www.PLessThan.com
arun
# 
Hi,

For your first condition, this could be used:
gsub("(\\d)[.].*","\\1",498888888.85)
[1] "498888888"
Second condition:
formatC(4333.78889,width=8,format="f",digits=2,flag="0")
#[1] "04333.79"
?formatC(884333.78889,width=8,format="f",digits=2,flag="0")
#[1] "884333.79"
Third condition:
sprintf("%.3f",0.0123556)
#[1] "0.012"

#You can create a function similar to this. (This still have some bugs).

?fun1<-function(x)
?ifelse(x>10^7,gsub("\\d)[.].*","\\1",x),ifelse(x<10^7 & x>1,formatC(x,width=8,format="f",digits=2,flag="0"),sprintf("%.3f",x))
?)
fun1(488.85)
#[1] "00488.85"
?fun1(0.1233555)
#[1] "0.123"


fun1(VALUES)
# [1] "123456789"? "12345678"?? "1234567.90" "123456.89"? "12345.79"? 
?#[6] "01234.68"?? "00123.57"?? "00012.46"?? "00001.35"?? "0.123"???? 
#[11] "0.012"????? "0.001"??? 


A.K.



----- Original Message -----
From: Dennis Fisher <fisher at plessthan.com>
To: r-help at stat.math.ethz.ch
Cc: 
Sent: Thursday, August 2, 2012 10:34 PM
Subject: [R] Formatting numbers for display

Colleagues

R 2.15.1
OS X

I have a lengthy script that generates a positive number that I display in a graphic using text.? The range of possible values is quite large and I am looking for an efficient means to format.? 
??? 1.? If the number is large (e.g., > 10^7), I want to display only the integer portion.
??? 2.? If it is less than 10^7 but > 1, I want to display 8 characters, e.g., 
??? ??? 12345.78
??? ??? 1234.678
??? ??? 123.5678
??? 3.? If it is less than 1, I want to display at least three significant digits, e.g.
??? ??? 0.123
??? ??? 0.0123
??? ??? 0.00123
??? ??? 0.000123
If there are any inconsistencies in my proposal, I apologize.

I can accomplish this by brute force with conditionals, -ceiling(log10(VALUE)), round.? However, I expect that there is a more efficient approach, possibly using sprint.

For the "dput"-ers, use the following as potential input:
VALUES??? <- c(123456789, 12345678, 1234567.9, 123456.89, 12345.789, 1234.6789, 123.56789, 12.456789, 1.3456789, 0.123456789, 0.0123456789, 0.00123456789)

Thanks for any thoughts.

Dennis

Dennis Fisher MD
P < (The "P Less Than" Company)
Phone: 1-866-PLessThan (1-866-753-7784)
Fax: 1-866-PLessThan (1-866-753-7784)
www.PLessThan.com

______________________________________________
R-help at r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
David Winsemius
#
On Aug 2, 2012, at 8:27 PM, arun wrote:

            

      
      
      
    

        
I didn't get the same results as requested with a wider variety of  
tests using those formatting methods. Here's what I could offer:

  form3 <- function (x) switch(findInterval(x, c( 0, 1, 10^7, Inf)),
                                      format(x, digits=3),
                                      formatC(x, width=8,  format="f",  
drop0trailing=FALSE),
                                      trunc(x) )

  tx <- c( 0.55555555, 55.555555555, 555555555555555.55555555)

 > sapply(tx, form3)
[1] "0.556"           " 55.5556"       "555555555555555"

(Still not getting the 8 digits in the intermediate value cases. Have  
not figured out how to get rid of leading space.)

  
    

      
      
    

  


  


      

    

    

      
      

        


  

        

      Berend Hasselman
    

    

      
      #
    

  


  

      
David Winsemius wrote

            

      
      
      
    

        
How about this to get rid of leading space:

form3 <- function (x) sub("^ +","", switch(findInterval(x, c( 0, 1, 10^7,
Inf)),
                                    format(x, digits=3),
                                    formatC(x, width=8,  format="f", 
drop0trailing=FALSE),
                                    trunc(x) )
                         )

Berend




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View this message in context: http://r.789695.n4.nabble.com/Formatting-numbers-for-display-tp4638991p4639018.html
Sent from the R help mailing list archive at Nabble.com.

  
  


  


      

    

    

      
      

        


  

        

      Tejas Kale
    

    

      
      #
    

  


  

      
I think the following code provides output that Dennis wants as well
as gets rid of the white space David mentioned.

digitTruncation <- function(x)
{
  ifelse(x>10^7, gsub("(\\d)[.].*", "\\1", x), ifelse(x<1, formatC(x, digits=3,
                                                                   format='fg'),
                                                      formatC(x,
width=length(x),
                                                              format='fg',
                                                              digits=8,
                                                              flag='')))
}


VALUES    <- c(123456789, 12345678, 1234567.9, 123456.89, 12345.789,
1234.6789, 123.56789, 12.456789, 1.3456789, 0.123456789, 0.0123456789,
0.00123456789)

digitTruncation(VALUES)
 [1] "123456789" "12345678"  "1234567.9" "123456.89" "12345.789"
"1234.6789" "123.56789" "12.456789" "1.3456789" "0.123"     "0.0123"
 "0.00123"

tx <- c( 0.55555555, 55.555555555, 555555555555555.55555555, 55.55)

digitTruncation(tx)
[1] "0.556"           "55.555556"       "555555555555556" "55.55"


Hope this helps.

Tejas

        
On Fri, Aug 3, 2012 at 1:41 PM, Berend Hasselman <bhh at xs4all.nl> wrote:

            

      
      
      
    

        

      
      
    

  
  


  


      

    

    

      
      

        


  

        

      arun
    

    

      
      #
    

  


  

      
HI,

I modified the code, thanks to Tejas.? Now, the results look like
fun1<-function(x)
?ifelse(x>10^7,gsub("\\d)[.].*","\\1",x),ifelse(x<10^7 & x>1,formatC(x,width=length(x),format="fg",digits=8,flag="",drop0trailing=FALSE),sprintf("%.3f",x)))

fun1(VALUES)
?[1] "123456789"??? "12345678"???? "?? 1234567.9" "?? 123456.89" "?? 12345.789"
?[6] "?? 1234.6789" "?? 123.56789" "?? 12.456789" "?? 1.3456789" "0.123"?????? 
[11] "0.012"??????? "0.001"??? 

David's code:
? form3 <- function (x) switch(findInterval(x, c( 0, 1, 10^7, Inf)), 
? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? format(x, digits=3), 
? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? formatC(x, width=8, ?format="f", ? 
drop0trailing=FALSE), 
? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? trunc(x) ) 
?sapply(VALUES,form3)
?[1] "123456789"??? "12345678"???? "1234567.9000" "123456.8900"? "12345.7890"? 
?[6] "1234.6789"??? "123.5679"???? " 12.4568"???? "? 1.3457"???? "0.123"?????? 
[11] "0.0123"?????? "0.00123"

#Modfied form3 a little:
form3 <- function (x) switch(findInterval(x, c( 0, 1, 10^7, Inf)),
????????????????????????????????????? formatC(x, width=8, format="f",digits=3),
????????????????????????????????????? formatC(x, width=8,? format="f",? 
drop0trailing=TRUE,flag="0"),
????????????????????????????????????? trunc(x) ) 
sapply(VALUES,form3)
?[1] "123456789" "12345678"? "1234567.9" "123456.89" "12345.789" "1234.6789"
?[7] "123.5679"? "012.4568"? "001.3457"? "?? 0.123"? "?? 0.012"? "?? 0.001" 

Still, there needs improvement.
? ? 
A.K.

?

----- Original Message -----
From: David Winsemius <dwinsemius at comcast.net>
To: Dennis Fisher <fisher at plessthan.com>
Cc: arun <smartpink111 at yahoo.com>; R help <r-help at r-project.org>
Sent: Friday, August 3, 2012 3:14 AM
Subject: Re: [R] Formatting numbers for display

        
On Aug 2, 2012, at 8:27 PM, arun wrote:

        

            

      
      
      
    

        
I didn't get the same results as requested with a wider variety of tests using those formatting methods. Here's what I could offer:

form3 <- function (x) switch(findInterval(x, c( 0, 1, 10^7, Inf)),
? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?  format(x, digits=3),
? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?  formatC(x, width=8,? format="f", drop0trailing=FALSE),
? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?  trunc(x) )

tx <- c( 0.55555555, 55.555555555, 555555555555555.55555555)

            

      
      
      
    

        
[1] "0.556"? ? ? ? ?  " 55.5556"? ? ?  "555555555555555"

(Still not getting the 8 digits in the intermediate value cases. Have not figured out how to get rid of leading space.)

--David.

            

      
      
      
    

        
Using the vector of long 5's

            

      
      
      
    

        
[1] "0.556"? ? ? ? ?  "00055.56"? ? ? ? "555555555555556"

            

      
      
      
    

        
David Winsemius, MD
Heritage Laboratories
West Hartford, CT