# Sorting local variables? Is this possible?

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Hey everyone. Could use a little assistance here. Not sure if this is even possible, but I assume it should be. I'm still in the "i know enough LISP just to be dangerous, but slightly useful" stage

I have a LISP routine that collects 5 variables from the user (r1,r2,r3,r4,r5).

```
(setq r1 (getint "\nEnter First Rev Line Number use ZERO for NONE: "))
(setq r2 (getint "\nEnter Second Rev Line Number use ZERO for NONE: "))
(if (= r2 0)(setq r3 0)(setq r3 (getint "\nEnter Third Rev Line Number use ZERO for NONE: ")))
(if (= r3 0)(setq r4 0)(setq r4 (getint "\nEnter Fourth Rev Line Number use ZERO for NONE: ")))
(if (= r4 0)(setq r5 0)(setq r5 (getint "\nEnter Fifth Rev Line Number use ZERO for NONE: ")))
```

What I would like to do with them, is sort them by their values, putting the highest value first, then sorting in reverse.

Can anyone offer any insight on this? Thank you in advance!

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Look into (vl-sort) It is a fairly simple function. -David

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Thanks David. I looked up some of the syntax for the vl-sort.. seems like it should be simple enough!

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Well I tried getting this to work, but I cant seem to make it happen using my variables.

I have something like this:

```  (setq r1 (getint "\nEnter First Rev Line Number use ZERO for NONE: "))
(setq r2 (getint "\nEnter Second Rev Line Number use ZERO for NONE: "))
(setq r3 (getint "\nEnter Third Rev Line Number use ZERO for NONE: "))
(setq r4 (getint "\nEnter Fourth Rev Line Number use ZERO for NONE: "))
(setq r5 (getint "\nEnter Fifth Rev Line Number use ZERO for NONE: "))

(setq revs (vl-sort '(r1 r2 r3 r4 r5) '>))
(setq r1 (nth 0 revs)
r2 (nth 1 revs)
r3 (nth 2 revs)
r4 (nth 3 revs)
r5 (nth 4 revs))```

When I try running that, I get a "error: bad argument type for compare: R2 R1". This is all pretty much guesswork for me as far as writing the code, so anything anyone can do to help me out would be greatly appreciated!

Thanks!

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By using quote to define the list you prevent his items from being evaluated:

`(setq revs (vl-sort ([color=red]list[/color] r1 r2 r3 r4 r5) '>))`

Regards,

Mircea

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Nice! Thanks!

Now all I need to do is figure out how to make it work if one of the values is zero...

Getting a " ; error: bad argument type: fixnump: nil" now..

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Pressing enter may be giving you a "nil" not a "0" there not the same

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Nice! Thanks!

Now all I need to do is figure out how to make it work if one of the values is zero...

Getting a " ; error: bad argument type: fixnump: nil" now..

Press Enter in Getint request will return nil If you want return 0, you can re-write like this :

```(mapcar '(lambda(a b)(set a b))
'(r1 r2 r3 r4 r5)
(vl-sort
(mapcar '(lambda(a)(cond ((getint (strcat "\nEnter " a "Rev Line Number use ZERO for NONE: ")))(0)))
'("First" "Second" "Third" "Fourth" "Fifth")
)
'>
)
)
```

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A little more elementary usage would be:

```(initget 1)
(setq r1 (getint "\nEnter First Rev Line Number use ZERO for NONE: "))
(initget 1)
(setq r2 (getint "\nEnter Second Rev Line Number use ZERO for NONE: "))
```

(initget) uses bit flags

The basic values are:

1 = not nil

2 = not zero

4 = not negative

so (initget 7) : would force an input of a positive number > 0

-David

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Thanks guys Ill have to give those a try.

I think I know the problem I'm running into.. In the code I tell it to sort 5 values, 2 or 3 of which may end up being 0. So after the list is sorted, the duplicates are removed, and if I try to pull the 4th and 5th values out of the list, they aren't there anymore.. So when the code tries to run:

`(setq r1 (nth 4 revs))`

.. that value basically doesn't exist anymore, thus returning the "nil" value. Am I understanding that correctly?

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Am I understanding that correctly?

Yes, this is true.

One simple alternative is to temporarily convert the revision indexes to strings and use ACAD_STRLSORT to sort them:

`(mapcar 'atoi (acad_strlsort (mapcar 'itoa '(5 0 3 0 1))))`

Regards,

Mircea

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Also simple

(if (= r1 nil)(setq r1 0))

```(if (= r1 nil)(setq r1 0))
or preset
(setq vert 50)
(prompt "\nEnter Vertical scale:<")
(prin1 vert)
(prompt ">:")
(setq newvert (getint))
(if (= newvert nil)
(princ)
(setq vert newvert)
)```

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