topic Re: does not return positive number in Visual LISP, AutoLISP and General Customization Forum

does not return positive number

dmjayaraj — Thu, 14 Jul 2022 11:45:24 GMT

Hi,

can anyone help in lisp

what is wrong with below lisp program line

it does not return positive number

any suggestion welcome.

(abs (atof (read-from-string (rtos (/ (cadr p) 1000)))))

Re: does not return positive number

Kent1Cooper — Thu, 14 Jul 2022 12:05:27 GMT

Show us the code for the (read-from-string) function, which is not in the AutoLisp Reference, and tell us what kind of value the 'p' variable would contain. Also, what does it return? It's hard to imagine it could be a negative number. Is it an error message? Something else?

Re: does not return positive number

dmjayaraj — Thu, 14 Jul 2022 12:25:27 GMT

(rtos (/ (cadr p) 1000))

cadr p is the y co-ordinates of 3d point which is real number (+ or - number)

Re: does not return positive number

Kent1Cooper — Thu, 14 Jul 2022 12:56:29 GMT

That answers only one of my three requests/questions.

Re: does not return positive number

dmjayaraj — Fri, 15 Jul 2022 03:01:54 GMT

Hi @Kent1Cooper ,

code attached hope this will helpful.

aim is to remove the sign of -x and -y co-ordinates

Re: does not return positive number

ВeekeeCZ — Fri, 15 Jul 2022 10:09:38 GMT

Still, there is used read-from-string function unknown to the program. The idea of this function probably comes from CommonLisp, but it does not exist in AutoLisp. So you either need to write your own function that would mimic the original functionality (or find/get the definition if the code is not yours) or use other functions built-in in AutoLisp.

Below is my version of the code...

(defun c:XYM ( / p)

  (while (setq p (getpoint "\nPick a head point: "))
    (command "_.LEADER" "_none" p pause ""
	     (strcat (if (> (car p) 0) "E=" "W=")
		     (rtos (/ (abs (car p)) 1000))
		     ","
		     (if (> (cadr p) 0) "N=" "S=")
		     (rtos (/ (abs (cadr p)) 1000)))
	     ""))
  (princ)
  )

Re: does not return positive number

dmjayaraj — Fri, 15 Jul 2022 10:01:59 GMT

can you reply back code for 3d point please

Re: does not return positive number

dmjayaraj — Fri, 15 Jul 2022 10:05:01 GMT

I tried and it is working fine with some changes

(defun c:XYZM ( / p)

(while (setq p (getpoint "\nPick a head point: "))
(command "_.LEADER" "_none" p pause ""
(strcat (if (> (car p) 0) "E=" "W=")
(rtos (/ (abs (car p)) 1000))
"\n"
(if (> (cadr p) 0) "N=" "S=")
(rtos (/ (abs (car p)) 1000))
"\n"
(if (> (caddr p) 0) "U=" "D=")
(rtos (/ (abs (caddr p)) 1000)))
""))
(princ)
)

Re: does not return positive number

ВeekeeCZ — Fri, 15 Jul 2022 10:42:57 GMT

@dmjayaraj wrote:

I tried and it is working fine with some changes

(defun c:XYZM ( / p)

(while (setq p (getpoint "\nPick a head point: "))
(command "_.LEADER" "_none" p pause ""
(strcat (if (> (car p) 0) "E=" "W=")
(rtos (/ (abs (car p)) 1000))
"\n"
(if (> (cadr p) 0) "N=" "S=")
(rtos (/ (abs (car p)) 1000))
"\n"
(if (> (caddr p) 0) "U=" "D=")
(rtos (/ (abs (caddr p)) 1000)))
""))
(princ)
)

What do you expect from me? Just fix the typo you should be good to go...

Re: does not return positive number

Kent1Cooper — Fri, 15 Jul 2022 11:26:37 GMT

Still nothing about the (read-from-string) function.

But in looking for places where the (abs) function is used to try to think of how that might be failing to remove the minus signs, I notice this line, and another like it for the Y coordinate:

(setq ptcoord1 (strcat "W="(abs (atof (read-from-string (rtos (/ (car p) 1000)) )))))

You can't concatenate a string with a number. The (abs (atof) ... function combination will return a number, not a text string such as (strcat) wants as an argument. It needs to be converted to a string, something like:

(setq ptcoord1 (strcat "W=" (rtos (abs (atof (read-from-string (rtos (/ (car p) 1000)) ))))))

But why that would leave the minus sign in place, I can't imagine, no matter what the (read-from-string) function does.

Re: does not return positive number

dmjayaraj — Fri, 15 Jul 2022 12:05:16 GMT

First thank you for your response

i was referring a site for the help on lisp same is attached as .png for read-from-string function.

Re: does not return positive number

Kent1Cooper — Fri, 15 Jul 2022 12:18:41 GMT

So let me get this straight. From Message 1:

(abs (atof (read-from-string (rtos (/ (cadr p) 1000)))))

would take a number (a Y coordinate) and divide it by 1000, turn that into a text string, then turn that back into a number, and get its absolute value. The (read-from-string) function looks like it's made to handle all sorts of different variations of input, but (cadr p), being a Y coordinate pulled from a point list, can't ever be anything other than a plain old real number. That can be handled with simply this instead of the above:

(abs (/ (cadr p) 1000))

If you change it to that, does it work right?

Re: does not return positive number

ВeekeeCZ — Fri, 15 Jul 2022 12:47:14 GMT

@dmjayaraj wrote:

First thank you for your response

i was referring a site for the help on lisp same is attached as .png for read-from-string function.

THIS would be a better source.