Remove Only Alphabetical Characters from String

[Tharwat]

Does lambda need more than one argument. I keep getting an error that says there are too few arguments?

Lambda is unnamed sub-function , so it can have as many argument as you want .

 

Can you post the code that you work for that is related to lambda at least at the moment ?

[ksperopoulos]

Here is what I have so far. I am also not sure what the string "Abcd12345x7789Z" is for either.

 

(defun c:insl ( / obj num)
(vl-load-com)
(setq obj (entget (car (entsel "\nSelect Object"))))
(setq num (cdr (nth 18 obj)))
(vl-string->list num)
(vl-remove-if
'(lambda (x)
 (not (member x '(46 48 49 50 51 52 53 54 55 56 57))
 )
)
)
(vl-list->string "Abcd12345X7789wZ")
(princ)
)

[Lee Mac]

Does lambda need more than one argument. I keep getting an error that says there are too few arguments?

 

A lambda function is simply an anonymous function definition, an unnamed 'defun' - it will hence accept as many or as few arguments as it has been defined to accept.

 

Here is an example of a lambda function accepting a single argument being evaluated by the vl-remove-if function:

 

_$ (vl-remove-if '(lambda ( a ) (= 2 a)) '(0 1 2 3 4 5 6))
(0 1 3 4 5 6)

 

Here is an example of a lambda function accepting two arguments being evaluated by the mapcar function:

 

_$ (mapcar '(lambda ( a b ) (* a (1+ b))) '(1 2 3 4) '(5 6 7 )
(6 14 24 36)

 

For more information on lambda, refer to my tutorial: Mapcar & Lambda

[Lee Mac]

Here is what I have so far. I am also not sure what the string "Abcd12345x7789Z" is for either.

 

Hopefully these comments will point you in the right direction:

 

(defun c:insl ( / obj num)
   
(vl-load-com)
   
(setq obj (entget (car (entsel "\nSelect Object"))))
[color=green]    ;; Be careful if the user does not select anything
   ;; as (entget nil) will error[/color]
   
(setq num (cdr (nth 18 obj)))
[color=green]    ;; I recommend using ASSOC to retrieve a DXF pair,
   ;; as you cannot rely on the DXF pair being in the
   ;; same position in the DXF list for every obejct[/color]
   
(vl-string->list num)
[color=green]    ;; This is redundant as you are not doing anything
   ;; with the value returned by the function[/color]


[color=green]    ;; I have formatted the following code so that you
   ;; can see the missing list argument:[/color]
(vl-remove-if
  '(lambda (x)
       (not (member x '(46 48 49 50 51 52 53 54 55 56 57))
       )
   )
)

[color=green]    ;; The following expression is also redundant as
   ;; you are not doing anything with the value returned.[/color]
(vl-list->string "Abcd12345X7789wZ")
   
(princ)
)

[ksperopoulos]

Lee Mac -

 

(setq num (cdr (nth 18 obj)))
[color=green]    ;; I recommend using ASSOC to retrieve a DXF pair,    ;; as you cannot rely on the DXF pair being in the    ;; same position in the DXF list for every obejct[/color]

 

I have to use this method due to multiple 300 dxf codes that are predetermined by the vertical AutoCad product I use.

 

(vl-string->list num)
[color=green]    ;; This is redundant as you are not doing anything    ;; with the value returned by the function[/color]

 

Instead of this, would you recommend doing it this way?

 

(setq num (vl-string->list (cdr (nth 18 obj)))

 

[color=#008000]    ;; I have formatted the following code so that you    ;; can see the missing list argument:[/color]
(vl-remove-if
  '(lambda (x)
       (not (member x '(46 48 49 50 51 52 53 54 55 56 57))
       )
   )
)

 

What you reformatted is exactly what I have in my code (see post #22). I am lost at this point. I have tried for hours now to figure this out with no luck at all.

[hmsilva]

Kyle,

Lee was pointing your code redundancies...

try this code

(defun c:insl (/ obj num str)
 (vl-load-com)
 (setq obj (entget (car (entsel "\nSelect Object"))))
 (setq num (cdr (nth 18 obj)))
 (setq str (vl-list->string
      (vl-remove-if
 '(lambda (x)
    (not (member x '(46 48 49 50 51 52 53 54 55 56 57))
    )
  )
 (vl-string->list num)
      )
    )
 )
 (alert (strcat "Your number is \nstored at str variable \nand is : " str))
 (princ)
)

 

HTH

Henrique

[ksperopoulos]

WOW! I was all sorts of messed up! I am still unclear how to use lambda, but I think the other stuff is making sense. I did have to make one revision to your code Henrique. I had to flip-flop the locations of (vl-list->string) and (vl-string->list) due to what was being returned. The value of the symbol "num" returns a string. I appreciate you and Lee (along with everyone else) trying to help me understand what is going on with the code. I am trying not to be one of those people who come on here and ask others to do their programming for them. Thanks a million!