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Re: Reading in Integers to a list
Posted: Tue Apr 06, 2010 6:09 pm
by Mercfh
Ok so it'd be something like
Code: Select all
defun readin()
(let ((list ;; <- this is the variable created, its value will be the next form
(loop for value = (prompt "Please enter an integer or \"end\" to finish:")
until (eq value 'end)
collect value)))
))
Btw thanks a ton. u've been a HUGE help
and then I can do something like
Code: Select all
(defun testing ()
(let ((test nil))
(readin())
(dolist (el *list*)
(insertf test el)
(print (frob-tree test)))
So it reads them all into a list first?
Re: Reading in Integers to a list
Posted: Tue Apr 06, 2010 6:49 pm
by gugamilare
Mercfh wrote:Ok so it'd be something like
Code: Select all
defun readin()
(let ((list ;; <- this is the variable created, its value will be the next form
(loop for value = (prompt "Please enter an integer or \"end\" to finish:")
until (eq value 'end)
collect value)))
))
Btw thanks a ton. u've been a HUGE help
and then I can do something like
Code: Select all
(defun testing ()
(let ((test nil))
(readin())
(dolist (el *list*)
(insertf test el)
(print (frob-tree test)))
So it reads them all into a list first?
No.
let will declare a
local variable, and the extent of that local variable finishes where the let finishes. In your example, the variable
list will only exist inside the function readin.
What you were supposed to do is this:
Code: Select all
(defun readin ()
(loop for value = (prompt "Please enter an integer or \"end\" to finish:")
until (eq value 'end)
collect value))
Then you create a variable in the function that calls this function:
Code: Select all
(defun your-function ()
(let ((list (readin)))
(dolist (element list)
(do-something-with element))))
Re: Reading in Integers to a list
Posted: Tue Apr 06, 2010 9:03 pm
by Mercfh
Ah Ok i think I understand.
Although our Professor emailed us because people were asking.
APPARENTLY i was just supposed to read in all the values into a list and then do the other functions. instead of what I initially thought (reading in an integer 1 by 1, then performing the task on it....1 by 1)
Although I think I understand now. I can just read them all into a list. but is there any way to kinda store the list as a "global variable"?
since before I had this as an example list
Code: Select all
(defparameter *example-list*
(list 4 6 4 18 8 2 14 7 15 5 19 12 15 5 9 0 17 2 2 19))
then I did this number on it
Code: Select all
(defun testing ()
(let ((test nil))
(dolist (ms *example-list*)
(insertf test ms)
(print (print-tree test)))
Or is the list you made using ur code already a global variable? so i can just replace *example-list* with it.
IM sorry for being such a newb with these things, but this is a basically learn on my own kinda thing sadly. (our teacher has been ill for the past 2 weeks, sadly no extension on our hw tho)
EITHER WAY, using ur code I get this error:
*** - EVAL: undefined function Ttree::PROMPT
ttree is the name of my package.
Re: Reading in Integers to a list
Posted: Tue Apr 06, 2010 9:57 pm
by nuntius
Re the global variable: Just (setf *example-list* new-value) -- though why not pass the list as a parameter?
Re the undefined function: Did you copy his prompt function into your package and compile it first?
Re: Reading in Integers to a list
Posted: Tue Apr 06, 2010 10:10 pm
by Mercfh
nuntius wrote:Re the global variable: Just (setf *example-list* new-value) -- though why not pass the list as a parameter?
Re the undefined function: Did you copy his prompt function into your package and compile it first?
Ya I put it in my package and ran (load "CS.lisp")
and it said *** - EVAL: undefined function PROMPT
I even just made it's OWN file like this
Code: Select all
(defpackage :test2
(:use :common-lisp))
(let ((list (loop for value = (prompt "Please enter an integer or \"end\" to finish:")
until (eq value 'end)
collect value)))
(format t "This is the list constructed: ~A~%" list)
(format t "These are its elements:")
(dolist (element list)
(format t "~A" element))
(format t "~%"))
and I still got that problem.
And I understand what you mean by the global variable. but I need a way to read the list INTO that global variable.
like:
Read data into list called *mylist*
then I can use that global variable on the other functions (which already work)
because here is my function that works perfectly (for my ternary tree)
Code: Select all
(defun testing()
(let ((test nil))
(dolist (hi *mylist*)
(insertf test hi)
(print (list-tree test)))))
im just using this right now as an example list
Code: Select all
(defparameter *example-list*
(list 4 6 4 18 8 2 14 7 15 5 19 12 15 5 9 0 17 2 2 19))
I need a way to read in numbers INTO that *example-list* or another global variable like it. if that makes sense? or if thats even possible
Re: Reading in Integers to a list
Posted: Wed Apr 07, 2010 5:10 am
by gugamilare
Mercfh wrote:nuntius wrote:Re the global variable: Just (setf *example-list* new-value) -- though why not pass the list as a parameter?
Re the undefined function: Did you copy his prompt function into your package and compile it first?
Ya I put it in my package and ran (load "CS.lisp")
and it said *** - EVAL: undefined function PROMPT
I even just made it's OWN file like this
Code: Select all
(defpackage :test2
(:use :common-lisp))
(let ((list (loop for value = (prompt "Please enter an integer or \"end\" to finish:")
until (eq value 'end)
collect value)))
(format t "This is the list constructed: ~A~%" list)
(format t "These are its elements:")
(dolist (element list)
(format t "~A" element))
(format t "~%"))
and I still got that problem.
You forgot to copy the function
prompt in my early posts.
Mercfh wrote:[...]
I need a way to read in numbers INTO that *example-list* or another global variable like it. if that makes sense? or if thats even possible
That is what he explained to you.
Se also
viewtopic.php?f=2&t=683&p=4263#p4263
Re: Reading in Integers to a list
Posted: Wed Apr 07, 2010 6:31 am
by Jasper
Don't forget (in-package the-package) then after that the things you declare in that file are actually in said page.