Re: [ferret_users] blank symbol

[Jaison Kurian <jaison@xxxxxxxxxxxxxxxxxx>]

Hi Mark,
          The PPL string editing using $EDIT have the following options
(see Ch7 Sec9.  PLOT+ STRING EDITING TOOLS and Appendix B Sec7.8.1  $EDIT).
The command syntax is 

    SET sym_out $EDIT (sym_in, arg1 [ arg2 arg3...] ) 

where, arg1 can be

    UPCASE   - changes string in sym_in to upper case
    TRIM     - trims leading and trailing blanks from sym_in
    COMPRESS - removes extra blanks from sym_in (reduces each group 
                     of blanks to a single blank)
    COLLAPSE - removes all blanks from sym_in 

So the answer to your question is "COLLAPSE". Here is a modified version
of your example :

       def sym a  a
       def sym b  ""
       def sym c  c
       def sym d  ($a)($b)($c)

       show sym d

       ppl set e  $EDIT (d, COLLAPSE)  ! no $ sign required for "d"

       show sym e

Ferret also offer few direct string editing tools which are listed in
Ch7 Sec2.  STRING FUNCTIONS. An example using string addition utility is
shown below:

       let a = "a"
       let b = ""
       let c = "c"
       let d = a + b + c

       say "d = `d`"

However, with b = " ", this method will fail (but will work fine with 
symbol example shown first).

Hope this helps....

Regards,

Jaison
 

On Mon, 17 Sep 2007 Mark.Collier@xxxxxxxx wrote:

> Hi Group,
> 
>  
> 
> If I:
> 
>  
> 
> yes? def sym a a
> 
> yes? def sym b b
> 
> yes? def sym c c
> 
> yes? def sym d ($a)($b)($c)
> 
> yes? show sym d
> 
> D = "abc"
> 
>  
> 
> However, if I define a blank symbol b like:
> 
>  
> 
> yes? def sym a a
> 
> yes? def sym b ""
> 
> yes? def sym c c
> 
> yes? def sym d ($a)($b)($c)
> 
> yes? show sym d
> 
> D = "a c"
> 
>  
> 
> Is it possible for the blank symbol to not take up any characters and
> produce "ac" automatically?
> 
> Regards,
> 
> Mark.
> 
> 
> 

-- 
This message has been scanned for viruses and
dangerous content by MailScanner, and is
believed to be clean.