### Inform User of Setup Completion

Source: https://www.afralisp.net/autolisp/tutorials/drawing-setup-part-3.php

Displays a blank line followed by a confirmation message to the user indicating that the setup routine is complete.

```autolisp
       (prompt "\n ")			;Blank Line
      (prompt "\nO.K Setup Routine Complete")		;Inform User

```

--------------------------------

### Entity Data List Output Example

Source: https://www.afralisp.net/autolisp/tutorials/into-the-database.php

Example of the association list structure returned by entget.

```AutoLISP
((-1 . <Entity name: 2680880>) (0 . "LINE") (5 . "270")
(100 . "AcDbEntity") (67 . 0) (8 . "0") (100 . "AcDbLine") 
(10 400.378 621.82 0.0) (11 740.737 439.601 0.0) 
(210 0.0 0.0 1.0))
```

--------------------------------

### Define and Setup Drawing Environment in AutoLISP

Source: https://www.afralisp.net/autolisp/tutorials/drawing-setup-part-3.php

This function defines a new command 'SETUP' that configures drawing environment settings like blip mode, command echo, and osmode. It also loads and interacts with a custom dialog box ('setup.dcl') to allow users to select drawing type and size, then proceeds to call specific setup functions based on user input.

```autolisp
(defun C:SETUP () 			;define function
     (setvar "BLIPMODE" 0) 			;switch off variables
     (setvar "CMDECHO" 0)
     (setvar "OSMODE" 0)
     (setq typ "e") 				;set default
     (setq dcl_id (load_dialog "setup.dcl")) 			;load dialogue
     (if (not 					;test if loaded
           (new_dialog "setup" dcl_id) 			;new dialogue
         ) 						;end not
           (exit) 					;if not loaded, exit
     ) 							;end if
     (set_tile "rb1" "1") 				;switch on radio button
     (action_tile "rb1" 				;if button selected
         "(setq typ \"e\") 			;store sheet type
          (mode_tile \"eb1\" 2)") 			;set focus to edit box
     (action_tile "rb2" 				;if button selected
         "(setq typ \"a\") 			;store sheet type
          (mode_tile \"eb1\" 2)") 			;set focus to edit box
     (action_tile "rb3" 				;if button selected
         "(setq typ \"c\") 			;store sheet type
          (mode_tile \"eb1\" 2)") 			;set focus to edit box
     (action_tile "rb4" 				;if button selected
         "(setq typ \"el\") 			;store sheet type
          (mode_tile \"eb1\" 2)") 			;set focus to edit box
     (action_tile "rb5" 				;if button selected
         "(setq typ \"b\") 			;store sheet type
          (mode_tile \"eb1\" 2)") 			;set focus to edit box
 
     (set_tile "rb6" "1") 				;make default
     (setq SIZ "A0") 					;Default sheet size
     (set_tile "eb1" "1") 				;initial edit box value
     (mode_tile "eb1" 2) 				;set focus to edit box
     (action_tile "rb6" 				;if button selected
         "(setq siz \"A0\") 			;store sheet size
          (mode_tile \"eb1\" 2)") 			;set focus to edit box
     (action_tile "rb7" 				;if button selected
         "(setq siz \"A1\") 			;store sheet size
          (mode_tile \"eb1\" 2)") 			;set focus to edit box
     (action_tile "rb8" 				;if button selected
         "(setq siz \"A2\") 			;store sheet size
          (mode_tile \"eb1\" 2)") 			;set focus to edit box
     (action_tile "rb9" 				;if button selected
         "(setq siz \"A3\") 			;store sheet size
          (mode_tile \"eb1\" 2)") 			;set focus to edit box
     (action_tile "rb10" 				;if button selected
         "(setq siz \"A4\") 			;store sheet size
          (mode_tile \"eb1\" 2)") 			;set focus to edit box
 
     (action_tile "cancel" 				;if Cancel selected
         "(done_dialog)(setq userclick nil)")			;close dialogue, clear flag
     (action_tile "accept" 				;if OK selected
       (strcat 					;string 'em together
      "(progn (setq #dwgsc 			;store value
              (atof (get_tile \"eb1\")))" 			;get edit box value
            "(done_dialog) (setq userclick T))"				;close dialogue, set flag
       ) 							;end progn
     ) 							;end action_tile
 
     (start_dialog) 					;start dialogue
     (unload_dialog dcl_id) 				;unload dialogue
 
(if userclick 					;if flag is true
    (progn 						;do the following
           (if (eq siz "A0") 				;If size is A0
             (progn 					;Do the following
		(setq x 1189.0				;Set x limits
                      y 841.0				;Set y limits
                )					;End setq
             ) 						;End progn
            )  						;End If
           (if (eq siz "A1") 				;If size is A1
             (progn 					;Do the following
		(setq x 841.0				;Set x limits
                      y 594.0				;Set y limits
                )					;End setq
             ) 						;End progn
            )  						;End If
           (if (eq siz "A2") 				;If size is A2
             (progn 					;Do the following
		(setq x 594.0				;Set x limits
                      y 420.0				;Set y limits
                )					;End setq
             ) 						;End progn
            )  						;End If
           (if (eq siz "A3") 				;If size is A3
             (progn 					;Do the following
		(setq x 420.0				;Set x limits
                      y 297.0				;Set y limits
                )					;End setq
             ) 						;End progn
            )  						;End If
           (if (eq siz "A4") 				;If size is A4
             (progn 					;Do the following
		(setq x 297.0				;Set x limits
                      y 210.0				;Set y limits
                )					;End setq
             ) 						;End progn
            )  						;End If
 
           (setq SIZE (strcat TYP SIZ))			;Construct name of Template
 
           (if (eq typ "e") (eng))			;Run Engineering Setup
           (if (eq typ "a") (arch))			;Run Architectural Setup
           (if (eq typ "c") (civil))			;Run Civil Setup
           (if (eq typ "el") (elec))			;Run Electrical Setup
           (if (eq typ "b") (blank))			;Run Blank Setup
       
    ) 							;End progn
  ) 							;End If
 
 (princ) 							;finish clean
)							;end function
;;;----------------------------------------------------------------------------
(defun blank ()					;Define function
 
      (setvar "DIMSCALE" #DWGSC)			;Set Dimscale
      (setvar "USERR1" #DWGSC)			;Store Scale for future
      (setvar "LTSCALE" ( #DWGSC 10))			;Set Ltscale
      (setvar "REGENMODE" 1)				;Regen ON
      (setvar "TILEMODE" 1)				;Tilemode ON
      (setq n ( 3.5 #DWGSC))				;Store Text Height
 

```

--------------------------------

### Select entities by window with user prompts

Source: https://www.afralisp.net/autolisp/tutorials/selection-sets.php

This example demonstrates how to use other AutoLISP functions to get user input for selection criteria, as prompts cannot be directly used within ssget.

```autolisp
	(setq sel1 (ssget "w" "\nSelect Objects by Window: "))

```

```autolisp
	(prompt "\nSelect Objects by Window")
	(setq p1 (getpoint "\nFirst Corner: "))
	(setq p2 (getpoint p1 "\nSecond Corner: "))
	(setq sel1 (ssget "w" p1 p2))


```

--------------------------------

### Example usage of findfile

Source: https://www.afralisp.net/autolisp/tutorials/locating-files.php

An example of searching for a specific file.

```AutoLISP

	(findfile "ACADR14.LSP)

```

```AutoLISP

	"C:\\ACADR14\\SUPPORT\\ACADR14.LSP"

```

--------------------------------

### Entity Name Output Example

Source: https://www.afralisp.net/autolisp/tutorials/into-the-database.php

Example of the return value when querying an entity name.

```AutoLISP
	<Entity name: 2680880>
```

--------------------------------

### Setup Drawing Limits and View

Source: https://www.afralisp.net/autolisp/tutorials/drawing-setup-part-3.php

Calculates drawing limits based on a scale factor and sets them using the LIMITS command. It then zooms to these limits. This is a common setup step before other drawing operations.

```autolisp
(setq L (list ( X #DWGSC) ( Y #DWGSC)))
      (
      (command "LIMITS" "0,0" L 
               "ZOOM" "W" "0,0" L

```

--------------------------------

### Conditional Setup Execution

Source: https://www.afralisp.net/autolisp/tutorials/drawing-setup-part-2.php

Conditional logic to trigger specific setup sub-routines based on the provided type variable.

```AutoLISP
(if (eq typ "a") (arch))		;Run Architectural Setup
           (if (eq typ "c") (civil))		;Run Civil Setup
           (if (eq typ "el") (elec))		;Run Electrical Setup
           (if (eq typ "b") (blank))		;Run Blank Setup
       
    )					;End progn
  )					;End If
 
 (princ)					;finish clean
)
```

--------------------------------

### AutoLISP SETQ and SET Example

Source: https://www.afralisp.net/autolisp/tutorials/set-and-setq.php

This example demonstrates dynamic symbol creation and assignment using SETQ and SET. It prompts the user for multiple points, stores them in dynamically named symbols, sorts them by Y-coordinate, and then draws a line connecting them. Use this when the number of variables is not known in advance.

```autolisp
(defun c:test ( / j lpt symb)
 
   (setq j 1)
   (while (set (read (strcat "point_" (itoa j)))
      (getpoint "\nPoint : ") 
      )
      (setq j (1+ j))
   )
   ;; Last point is nil.
   (setq j (1- j))
   ;; Sort the points. See function "sortpoints" below.
   (sortpoints j)
   ;; Initialize the list of points to be passed to (command "_line")
   (setq lpt (list ""))
   ;; Construct the list and set each of our 
   ;; "on the fly" symbols to nil
    (while (> j 0)
      (setq 
         symb (read (strcat "point_" (itoa j)))
         lpt (cons (eval symb) lpt)
      )
      (set symb nil)
      (setq j (1- j))
   )
   ;; draw the line
   (command "_line")
   (mapcar 'command lpt)
   (princ)
)


;; This function sorts the points by their Y coordinate
(defun sortpoints (j / i cur_y prev_y cur_symb prev_symb point)
   (setq i 2)
   (while (<= i j)
      (setq 
         cur_symb (read (strcat "point_" (itoa i)))
         prev_symb (read (strcat "point_" (itoa (1- i))))
         cur_y (cadr (eval cur_symb))
         prev_y (cadr (eval prev_symb))
      )
      (if (> cur_y prev_y)
         (progn 
            (setq   point (eval prev_symb))
            (set    prev_symb (eval cur_symb))
            (set    cur_symb point)
            (if (/= i 2) (setq i (1- i)))
         )
      (setq i (1+ i))
      )
   )
)
```

--------------------------------

### Command Line Usage Example (AutoLISP)

Source: https://www.afralisp.net/autolisp/tutorials/polyline-bulges-part-1.php

Demonstrates how to use the getPolySegs and getArcInfo functions from the AutoCAD command line. First, call getPolySegs to get the polyline segments, then use nth to select a specific segment and pass it to getArcInfo.

```autolisp
Command: (setq myPoly (getPolySegs))
Select polyline: [select a polyline]
```

```autolisp
Command: (getArcInfo (nth 1 myPoly))
```

--------------------------------

### Coordinate Output Example

Source: https://www.afralisp.net/autolisp/tutorials/into-the-database.php

Example of the coordinate list returned after extraction.

```AutoLISP
	(400.378 621.82 0.0)
```

--------------------------------

### Blank Drawing Setup Function

Source: https://www.afralisp.net/autolisp/tutorials/drawing-setup-part-2.php

Configures drawing system variables, calculates limits, and inserts a template drawing.

```AutoLISP
(defun blank ()				;Define function
 
      (setvar "DIMSCALE" #DWGSC)		;Set Dimscale
      (setvar "USERR1" #DWGSC)			;Store Scale for future
      (setvar "LTSCALE" ( #DWGSC 10))		;Set Ltscale
      (setvar "REGENMODE" 1)			;Regen ON
      (setvar "TILEMODE" 1)			;Tilemode ON
      (setq n ( 3.5 #DWGSC))			;Store Text Height
 
      (setq L (list ( X #DWGSC) ( Y #DWGSC))	;Calculate Limits
      )
 
      (command "LIMITS" "0,0" L 
               "ZOOM" "W" "0,0" L
	       "STYLE" "italict"
               "italict" N "" "" "" "" ""
               "INSERT" SIZE "0,0" #DWGSC "" ""
      )					;Set Up Drawing
       (prompt "\n ")				;Blank Line
      (prompt "\nOK Setup Routine Complete")	;Inform User
 
 (princ)					;Exit Quietly
) 					;End Function
```

--------------------------------

### Load Custom Utilities via S::STARTUP

Source: https://www.afralisp.net/autolisp/tutorials/redefining-commands.php

Ensures custom AutoLISP routines are loaded automatically when AutoCAD starts.

```AutoLISP
(defun S::STARTUP ()
       (prompt "\nAfraLisp Custom Utilities Loaded....\n")
       (load "REDEFS" "\nREDEFS.LSP not found")
    (princ)
);defun

```

--------------------------------

### Implementing Global Variable Utilities

Source: https://www.afralisp.net/autolisp/tutorials/saving-system-variables.php

Example of how to integrate the global varget and varset functions into a standard routine.

```AutoLISP
(defun c:example ()
 
	(varget)
	;store system variables and then reset them
 
	Programme statements…
 
	(varset)
	;restore system variables
 
  (princ)
);defun
;******************************************************
```

--------------------------------

### Example MainList Structure in AutoLISP

Source: https://www.afralisp.net/autolisp/tutorials/efficient-variables.php

This example shows the potential structure of the 'MainList' variable after items have been added using the 'AList' function. It contains both point data and system variable settings.

```autolisp
(("FourthPoint" 456.598 514.007 0.0) ("ThirdPoint" 676.92 293.827 0.0) 
("SecondPoint" 1030.95 526.155 0.0) ("FirstPoint" 576.636 732.669 0.0) 
("OLDECHO" . 0) ("OLDHIGH" . 1) ("OLDSNAP" . 32))
```

--------------------------------

### Efficient List Routine Example

Source: https://www.afralisp.net/autolisp/tutorials/efficient-variables.php

A complete routine demonstrating the use of helper functions to manage variable storage efficiently.

```AutoLisp
(defun c:efflist ( / AnItem item MainList)
 
	(setq AnItem (getvar "OSMODE"))
	;get the snap setting
 
	(AList "OLDSNAP" AnItem)
	;add it to the list
 
	(setq AnItem (getvar "HIGHLIGHT"))
	;get the highlight setting
 
	(AList "OLDHIGH" AnItem)
	;add it to the list
 
	(setq AnItem (getvar "CMDECHO"))
	;get the command echo setting
 
	(AList "OLDECHO" AnItem)
	;add it to the list
 
	(setvar "Osmode" 32)
	;reset snap to intersection
 
	(setvar "Highlight" 0)
	;switch off highlight
 
	(setvar "Cmdecho" 0)
	;switch off command echo
 
	(setq AnItem (getpoint "\nSelect First Point : "))
	;get the first point
 
	(AList "FirstPoint" AnItem)
	;add it to the list
 
	(setq AnItem (getpoint AnItem "\nSelect Second Point : "))
	;get the second point
 
	(AList "SecondPoint" AnItem)
	;add it to the list
 
	(setq AnItem (getpoint AnItem "\nSelect Third Point : "))
	;get the third point
 
	(AList "ThirdPoint" AnItem)
	;add it to the list
 
	(setq AnItem (getpoint AnItem "\nSelect Fourth Point : "))
	;get the fourth point
 
	(AList "FourthPoint" AnItem)
	;add it to the list
 
	(command "Line" (RList "FirstPoint")
			(RList "SecondPoint")
			(RList "ThirdPoint")
			(RList "FourthPoint")
			"C"
	)
	;retrieve all the point values and draw the shape
 
	(setvar "OSMODE" (RList "OLDSNAP"))
	;retrieve and reset snap
```

--------------------------------

### Define Architectural Setup Function

Source: https://www.afralisp.net/autolisp/tutorials/drawing-setup-part-3.php

Defines the 'arch' function in AutoLISP, which sets up drawing variables like DIMSCALE, USERR1, LTSCALE, REGENMODE, and TILEMODE, and then calls the common drawing setup commands.

```autolisp
(defun arch () 					;Define function
 
      (setvar "DIMSCALE" #DWGSC)			;Set Dimscale
      (setvar "USERR1" #DWGSC)				;Store Scale for future
      (setvar "LTSCALE" ( #DWGSC 10))			;Set Ltscale
      (setvar "REGENMODE" 1)				;Regen ON
      (setvar "TILEMODE" 1)				;Tilemode ON
      (setq n ( 3.5 #DWGSC))				;Store Text Height
 
      (setq L (list ( X #DWGSC) ( Y #DWGSC)))			;Calculate Limits
      )
 
      (command "LIMITS" "0,0" L 
               "ZOOM" "W" "0,0" L
	       "STYLE" "italict"
               "italict" N "" "" "" "" ""
               "INSERT" SIZE "0,0" #DWGSC "" ""
      )								;Set Up Drawing
       (prompt "\n ")					;Blank Line
      (prompt "\nO.K Setup Routine Complete")					;Inform User
 
 (princ)							;Exit Quietly
)								;End Function

```

--------------------------------

### Command Output Example

Source: https://www.afralisp.net/autolisp/tutorials/polyline-bulges-part-2.php

Example output displayed in the AutoCAD command line when running the polyarcs command.

```text
Command: polyarcs
Select polyline:
Segment 2:
 Included angle: 2.9932 rad (171.4974 degrees)
 Height of arc:  1.1422
 Chord length:   2.4605
 Radius of arc:  1.2336
 Center of arc:  -9.4965,14.9290
Segment 4:
 Included angle: 0.9844 rad (56.3997 degrees)
 Height of arc:  0.4201
 Chord length:   3.3447
 Radius of arc:  3.5390
 Center of arc:  -5.8690,19.3390
Segment 5:
 Included angle: 1.6177 rad (92.6872 degrees)
 Height of arc:  0.5787
 Chord length:   2.7043
 Radius of arc:  1.8689
 Center of arc:  -2.1545,17.4054
```

--------------------------------

### nentsel Output Example

Source: https://www.afralisp.net/autolisp/tutorials/polylines-and-blocks.php

Sample output returned by nentsel when selecting a vertex.

```AutoLISP
Select object: ((-1 . <Entity name: 2100880>) (0 . "POLYLINE") (5 . "270")
  (100 . "AcDbEntity") (67 . 0) (8 . "0") (100 . "AcDb3dPolyline") (66 . 1)
```

--------------------------------

### Entity List Examples

Source: https://www.afralisp.net/autolisp/tutorials/quick-start.php

Examples of entity data structures stored in the AutoCAD database.

```AutoLISP
( - 1 <Entity name: 60000014) (0 "CIRCLE") (8 . "LAYER1")
```

```AutoLISP
(10 . 50.000 100.000) (40 . 60.000)
```

--------------------------------

### Define Electrical Setup Function

Source: https://www.afralisp.net/autolisp/tutorials/drawing-setup-part-3.php

Defines the 'elec' function in AutoLISP, which sets up drawing variables like DIMSCALE, USERR1, LTSCALE, REGENMODE, and TILEMODE, and then calls the common drawing setup commands.

```autolisp
(defun elec () 					;Define function
 
      (setvar "DIMSCALE" #DWGSC)			;Set Dimscale
      (setvar "USERR1" #DWGSC)				;Store Scale for future
      (setvar "LTSCALE" ( #DWGSC 10))			;Set Ltscale
      (setvar "REGENMODE" 1)				;Regen ON
      (setvar "TILEMODE" 1)				;Tilemode ON
      (setq n ( 3.5 #DWGSC))				;Store Text Height
 
      (setq L (list ( X #DWGSC) ( Y #DWGSC)))			;Calculate Limits
      )
 
      (command "LIMITS" "0,0" L 
               "ZOOM" "W" "0,0" L
	       "STYLE" "italict"
               "italict" N "" "" "" "" ""
               "INSERT" SIZE "0,0" #DWGSC "" ""
      )								;Set Up Drawing
       (prompt "\n ")					;Blank Line
      (prompt "\nO.K Setup Routine Complete")					;Inform User
 
 (princ)							;Exit Quietly
)								;End Function

```

--------------------------------

### Load AutoLISP via Toolbar

Source: https://www.afralisp.net/autolisp/tutorials/loading-autolisp-files.php

Example of loading a routine from a toolbar button, incorporating a check to prevent redundant loading.

```AutoLISP
***TOOLBARS
**STEEL
TB_DDSTEEL [_Button("Steel", "STEEL.bmp",
"STEEL32.bmp")]^C^C^P+
(cond ((null C:ddsteel) (prompt "Please Wait...")(load "ddsteel"))) ddsteel
```

--------------------------------

### Define Engineering Setup Function

Source: https://www.afralisp.net/autolisp/tutorials/drawing-setup-part-3.php

Defines the 'eng' function in AutoLISP, which sets up drawing variables like DIMSCALE, USERR1, LTSCALE, REGENMODE, and TILEMODE, and then calls the common drawing setup commands.

```autolisp
(defun eng () 					;Define function
 
      (setvar "DIMSCALE" #DWGSC)			;Set Dimscale
      (setvar "USERR1" #DWGSC)				;Store Scale for future
      (setvar "LTSCALE" ( #DWGSC 10))			;Set Ltscale
      (setvar "REGENMODE" 1)				;Regen ON
      (setvar "TILEMODE" 1)				;Tilemode ON
      (setq n ( 3.5 #DWGSC))				;Store Text Height
 
      (setq L (list ( X #DWGSC) ( Y #DWGSC)))			;Calculate Limits
      )
 
      (command "LIMITS" "0,0" L 
               "ZOOM" "W" "0,0" L
	       "STYLE" "italict"
               "italict" N "" "" "" "" ""
               "INSERT" SIZE "0,0" #DWGSC "" ""
      )								;Set Up Drawing
       (prompt "\n ")					;Blank Line
      (prompt "\nO.K Setup Routine Complete")					;Inform User
 
 (princ)							;Exit Quietly
)								;End Function

```

--------------------------------

### Routine Using System Variable Management Functions

Source: https://www.afralisp.net/autolisp/tutorials/list-manipulation.php

This example shows how to integrate 'varget' and 'varset' into a routine to manage system variables effectively.

```autolisp
(defun c:example ()

	(varget)
	;store system variables and then reset them

	Programme statements……..
	……..

	(varset)
	;restore system variables

  (princ)
);
defun
;******************************************************

```

--------------------------------

### Drawing Log Routine

Source: https://www.afralisp.net/autolisp/tutorials/file-handling.php

A practical example that logs drawing session details to an ASCII text file.

```AutoLISP
(defun C:LOGIN ( / a c d file fp)
   (setq file (findfile "LOG.TXT"))
   (if (not file)
	(open "LOG.TXT" "w")
   );if
   (setq a (TODAY)
      TIME1 (TIME)
      c (getvar "DWGNAME")
      d (strcat "Drg Start   " a "  -  " TIME1 "  -  " c)
   );setq
   (if (/= c "Drawing.dwg")
      (progn  
         (setq file (findfile "LOG.TXT")
            fp (open file "a")
         );setq
         (princ d fp)
         (princ "\n" fp)
         (close fp)
         (princ (strcat "\nLogged in at : " TIME1))
      );progn
   );if
   (princ)
);defun
;;;*-------------------------------------------------
(defun C:LOGOUT ( / a c d file fp)
   (setq a (TODAY)
      TIME2 (TIME)
      c (getvar "DWGNAME")
      d (strcat "Drg Exit    " a "  -  " TIME2 "  -  " c)
   );setq
   (if (/= c "Drawing.dwg")
      (progn  
         (setq file (findfile "LOG.TXT")
            fp (open file "a")
         );setq
         (princ d fp)
         (princ "\n" fp)
         (close fp)
         (princ (strcat "\nLogged out at : " TIME2))
         (etime)
      );progn
   );if
   (princ)
);defun
;;;*-------------------------------------------------
(defun ETIME ( / hr1 m1 s1 tot1 hr2 m2 s2 tot2 total ht mt file fp)
   (setq hr1 (* 60 (* 60 (atof (substr time1 1 2))))
      m1 (* 60 (atof (substr time1 4 2)))
      s1 (atof (substr time1 7 2))
      tot1 (+ hr1 m1 s1)
      hr2 (* 3600 (atof (substr time2 1 2)))
      m2 (* 60 (atof (substr time2 4 2)))
      s2 (atof (substr time2 7 2))
      tot2 (+ hr2 m2 s2)
      total (- tot2 tot1)
      hr1 (/ total 3600)
      ht (fix hr1)
      hr1 (- hr1 ht)
      mt (* hr1 60)
      ht (rtos ht)
      mt (rtos mt) 
   );setq
```

--------------------------------

### AutoLISP IF Statement Example

Source: https://www.afralisp.net/autolisp/tutorials/conditionals.php

A practical example demonstrating the IF statement to compare two numbers entered by the user and print a message indicating if they are equal or not.

```autolisp
(defun c:testif ()
	(setq a (getreal "\nEnter a Number : ")
	      b (getreal "\nEnter Second Number : ")
	);setq
	(if (= a b)
		(prompt "\nBoth Numbers are equal")
		(prompt "\nBoth numbers are not equal")
	);if
   (princ)
);defun
(princ)

```

--------------------------------

### AutoLISP COND Function Example

Source: https://www.afralisp.net/autolisp/tutorials/conditionals.php

Provides an example of the COND function, which evaluates multiple conditions sequentially and executes the code associated with the first true condition.

```autolisp
(defun c:testcond ()
	(setq a
	   (strcase (getstring "\nSize of Bolt (M10,M12,M16): ")
	   );strcase
	);setq
	(cond
		((= a "M10") (prompt "\nYou have choosen M10"))
		((= a "M12") (prompt "\nYou have choosen M12"))
		((= a "M16") (prompt "\nYou have choosen M16"))
		(T (prompt "\nUnknown Bolt Size"))
	);cond
   (princ)
);defun
(princ)

```

--------------------------------

### Example Polyline Entity Data

Source: https://www.afralisp.net/autolisp/tutorials/polylines-and-blocks.php

Sample output returned by entget for a 3D Polyline entity.

```AutoLISP
Select object: ((-1 . <Entity name: 26508d8>) (0 . "POLYLINE") (5 . "27B")
  (100 . "AcDbEntity") (67 . 0) (8 . "0") (100 . "AcDb3dPolyline") (66 . 1)
  (10 0.0 0.0 0.0) (70 . 8) (40 . 0.0) (41 . 0.0) (210 0.0 0.0 1.0) (71 . 0)
  (72 . 0) (73 . 0) (74 . 0) (75 . 0))
```

--------------------------------

### Deeply Nested ssget Filter Example

Source: https://www.afralisp.net/autolisp/tutorials/selection-set-filters.php

An example of deeply nested conditional operators (XOR, OR, XOR, AND) within an ssget filter. This demonstrates complex selection logic.

```autolisp
(ssget '( 
   (-4 . "<xor") (8 . "mylayer") 
   (-4 . "<or") (0 . "text") 
   (-4 . "<xor") (8 . "notes") 
   (-4 . "<and") (62 . 2) (0 . "line") (-4 . "and>") 
   (-4 . "xor>") 
   (-4 . "or>") 
   (-4 . "xor>")
))
```

--------------------------------

### List Definition for Foreach

Source: https://www.afralisp.net/autolisp/tutorials/mapcar-and-lambda.php

Defines a sample list 'a' used in the foreach example.

```autolisp
(setq a '(1 2 3 4 5))
```

--------------------------------

### Load AutoLISP via Pull Down Menu

Source: https://www.afralisp.net/autolisp/tutorials/loading-autolisp-files.php

Example of loading a routine from a pull-down menu, including a check to see if the routine is already loaded.

```AutoLISP
***POP12
T_Steel [Steel Menu]
T_Beams [Drawing Setup]^C^C^P+
(cond ((null C:DDSTEEL) (prompt "Please Wait...")(load "DDSTEEL")))
DDSTEEL
```

--------------------------------

### Define a basic AutoLISP function

Source: https://www.afralisp.net/autolisp/tutorials/the-define-function.php

The standard syntax for starting an AutoLISP routine definition.

```AutoLISP
(defun C:DDSTEEL ( / t1 t2 h1 h2 ang)
```

--------------------------------

### Example usage of getfiled

Source: https://www.afralisp.net/autolisp/tutorials/locating-files.php

A routine that opens a specific directory and prompts the user to select a slide file.

```AutoLISP

(defun c:slv ( / sl)
	(setq sl (getfiled "Pick a slide to view"
			   "C:/SLIDES/"
			   "sld"
			   10
		 );getfiled
	);
	(command "vslide" sl)
   (princ)
);defun
(princ)

```

--------------------------------

### Example Layer Entity List

Source: https://www.afralisp.net/autolisp/tutorials/into-the-database.php

The returned entity list structure after a successful tblsearch operation.

```lisp
((0 . "LAYER") (2 . "STEEL") (70 . 64) (62 . 7) (6 . "CONTINOUS"))
```

--------------------------------

### Example Layer Entity List from tblnext

Source: https://www.afralisp.net/autolisp/tutorials/into-the-database.php

The returned entity list structure after a successful tblnext operation.

```lisp
((0 . "LAYER") (2 . "PIPE") (70 . 0) (62 . 7) (6 . "CONTINUOUS"))
```

--------------------------------

### Example Xdata Structure

Source: https://www.afralisp.net/autolisp/tutorials/extended-entity-data-part-1.php

Illustrates the basic structure of Extended Entity Data, showing a string value associated with the code 1000.

```autolisp
((-3 ("AFRALISP" (1000 . "Kenny is great"))))
```

--------------------------------

### AutoLISP EQUAL Function Example

Source: https://www.afralisp.net/autolisp/tutorials/conditionals.php

Demonstrates the EQUAL function for comparing two expressions for equality, including an optional fuzz argument for floating-point comparisons.

```autolisp
(setq a '(x y z))
(setq b '(x y z))
(setq c b)
(setq m 1.123456))
(setq n 1.123457))
 
(equal a c) would return true.
(equal c b) would return true.
(equal m n) would return nil.
(equal m n 0.000001) would return true.

```

--------------------------------

### AutoLISP (repeat) Loop Example

Source: https://www.afralisp.net/autolisp/tutorials/program-looping.php

Use (repeat) to execute a block of code a specified number of times. The loop counter must be an integer.

```autolisp
(defun c:loop ()
	(setq pt (getpoint "\nCentre of Rotation : "))
	(setq n  (getint "Enter Number of Steps : "))
 
	(repeat n
		(command "Rotate" "L" "" pt "20")
	)
   (princ)
)
```

--------------------------------

### Loop Through Selection Set

Source: https://www.afralisp.net/autolisp/tutorials/quick-start.php

Starts a loop that will repeat `n` times, processing each entity in the selection set `a1`.

```autolisp
(repeat n
```

--------------------------------

### Get User Input Point in AutoLISP

Source: https://www.afralisp.net/autolisp/tutorials/list-manipulation.php

Prompts the user to select a point in the drawing and stores it as a list of coordinates. This is a common starting point for many AutoLISP routines.

```autolisp
	(setq pt1 (getpoint "\nChoose a Point : "))


```

--------------------------------

### Calculate a Point using Polar

Source: https://www.afralisp.net/autolisp/tutorials/the-basics-part-3.php

Example of calculating a point p2 relative to an insertion point ip using the polar function.

```AutoLisp
	(setq p2 (polar ip (dtr 180.0) (- (/ lb 2) nl)))
```

--------------------------------

### Get Arc Information from Segment (AutoLISP)

Source: https://www.afralisp.net/autolisp/tutorials/polyline-bulges-part-1.php

This function calculates and prints geometric information about an arc segment, given a list containing its start vertex, bulge value, and end vertex. It handles cases where the segment is a straight line (bulge = 0.0) to prevent errors. Ensure the input segment is valid and has a non-zero bulge for arc calculations.

```autolisp
(defun getArcInfo (segment / a p1 bulge p2 c c|2 gamma midp p phi r r2 s theta)
  ;; assign variables to values in argument
  (mapcar 'set '(p1 bulge p2) segment)
  ;; find included angle
  ;; remember that bulge is negative if drawn clockwise
  (setq theta (* 4.0 (atan (abs bulge))))
  ;; output included angle
  (princ (strcat "\n Included angle: "
                 (rtos theta)
                 " rad ("
                 (angtos theta 0)
                 " degrees)"
         )
  )
  ;; find height of the arc
  (setq c (distance p1 p2)
        s (* (/ c 2.0) (abs bulge))
  )
  ;; output height of arc
  (princ (strcat "\n Height of arc:  " (rtos s)))
  ;; output chord length
  (princ (strcat "\n Chord length:   " (rtos c)))
  ;; If this function is used without making sure that the segment
  ;; is not simply a line segment (bulge = 0.0), it will produce
  ;; a division-by-zero error in the following. Therefore we want
  ;; to be sure that it doesn't process line segments.
  (cond ((not (equal bulge 0.0 1E-6))
         ;; find radius of arc
         ;; first find half the chord length
         (setq c|2 (/ c 2.0)
               ;; find radius with Pythagoras (used as output)
               r   (/ (+ (expt c|2 2.0) (expt s 2.0)) (* s 2.0))
               ;; find radius with trigonometry
               r2  (/ c|2 (sin (/ theta 2.0)))
         )
         (princ (strcat "\n Radius of arc:  " (rtos r)))
         ;; find center point of arc with angle arithmetic
         ;; (used as output)
         (setq gamma (/ (- pi theta) 2.0)
               phi   (if (>= bulge 0)
                       (+ (angle p1 p2) gamma)
                       (- (angle p1 p2) gamma)
                     )
               p     (polar p1 phi r)
         )
         ;; find center point of arc with Pythagoras
         (setq a    (sqrt (- (expt r 2.0) (expt c|2 2.0)))
               midp (polar p1 (angle p1 p2) c|2)
               p2   (if (>= bulge 0)
                      (polar midp (+ (angle p1 p2) (/ pi 2.0)) a)
                      (polar midp (- (angle p1 p2) (/ pi 2.0)) a)
                    )
         )
         ;; output coordinates of center point
         (princ (strcat "\n Center of arc:  "
                        (rtos (car p))
                        ","
                        (rtos (cadr p))
                )
         )
        )
        (T (princ "\n Segment has no arc info"))
  )
  (princ)
)
```

--------------------------------

### Playback commands using (eval)

Source: https://www.afralisp.net/autolisp/tutorials/the-eval-function.php

Shows how to store commands in a list and execute them using (eval).

```AutoLisp
	(setq lst '(command "circle" pt2 rad))
	(eval lst)
```

--------------------------------

### Create a basic selection set with ssget

Source: https://www.afralisp.net/autolisp/tutorials/selection-sets.php

Use ssget without arguments to allow the user to select entities using any method.

```autolisp
	(setq sel1 (ssget))


```

--------------------------------

### Create a List with (list)

Source: https://www.afralisp.net/autolisp/tutorials/mapcar-and-lambda.php

Demonstrates two ways to create a list in AutoLISP: using the (list) command or using quote with parentheses.

```autolisp
(setq a (list 1 2 3 4 5))
```

```autolisp
(setq a '(1 2 3 4 5))
```

--------------------------------

### AutoLISP OR Logical Operator Example

Source: https://www.afralisp.net/autolisp/tutorials/conditionals.php

An example showcasing the OR logical operator to check if user input for gender is either 'y' or 'Y', printing a corresponding greeting.

```autolisp
(defun c:testor ()
	(setq a (getstring "\nAre you Male? Y/N : "))
	(if 
	    (or
	      	(= a "y")
		(= a "Y")
	    );or
		(prompt "\nHello Sir")
		(prompt "\nHello Madam")
	);if
    (princ)
);defun
(princ)

```

--------------------------------

### Load and Display Dialogue Box in AutoLISP

Source: https://www.afralisp.net/autolisp/tutorials/drawing-setup-part-1.php

This AutoLISP function, C:SETUP2, loads and displays a custom dialogue box. It initializes system variables, loads the DCL file, and handles user interactions with radio buttons and the accept/cancel buttons.

```autolisp
(defun C:SETUP2 () 
     (setvar "BLIPMODE" 0) 
     (setvar "CMDECHO" 0) 
     (setvar "OSMODE" 0) 
     (setq typ "e") 
     (setq dcl_id (load_dialog "setup2.dcl")) 
     (if (not 
           (new_dialog "setup2" dcl_id) 
         ) 
           (exit) 
     ) 
     (set_tile "rb1" "1") 
     (action_tile "rb1" 
         "(setq typ \"e\") 
          (mode_tile \"eb1\" 2)") 
     (action_tile "rb2" 
         "(setq typ \"a\") 
          (mode_tile \"eb1\" 2)") 
     (action_tile "rb3" 
         "(setq typ \"c\") 
          (mode_tile \"eb1\" 2)") 
     (action_tile "rb4" 
         "(setq typ \"el\") 
          (mode_tile \"eb1\" 2)") 
     (action_tile "rb5" 
         "(setq typ \"b\") 
          (mode_tile \"eb1\" 2)") 
 
     (set_tile "rb6" "1") 
     (set_tile "eb1" "1") 
     (mode_tile "eb1" 2) 
     (action_tile "rb6" 
         "(setq siz \"A0\") 
          (mode_tile \"eb1\" 2)") 
     (action_tile "rb7" 
         "(setq siz \"A1\") 
          (mode_tile \"eb1\" 2)") 
     (action_tile "rb8" 
         "(setq siz \"A2\") 
          (mode_tile \"eb1\" 2)") 
     (action_tile "rb9" 
         "(setq siz \"A3\") 
          (mode_tile \"eb1\" 2)") 
     (action_tile "rb10" 
         "(setq siz \"A4\") 
          (mode_tile \"eb1\" 2)") 
 
     (action_tile "cancel" 
         "(done_dialog)(setq userclick nil)") 
     (action_tile "accept" 
       (strcat 
      "(progn (setq #dwgsc 
              (atof (get_tile \"eb1\")))" 
            "(done_dialog) (setq userclick T))" 
       ) 
     ) 
 
     (start_dialog) 
     (unload_dialog dcl_id) 
 (princ) 
) 
(princ)

```

--------------------------------

### Get Entity Data for Target Layer

Source: https://www.afralisp.net/autolisp/tutorials/quick-start.php

Retrieves the entity data list for the entity selected in `a2` and assigns it to `b2`. This is used to get the layer information.

```autolisp
(setq b2 (entget (car a2)))
```

--------------------------------

### Create Entities

Source: https://www.afralisp.net/autolisp/tutorials/polylines-and-blocks.php

Compare standard command-based drawing with direct entity creation using entmake.

```AutoLISP
	(command "Line" pt1 pt2 "")
```

```AutoLISP
(setq e '((0 . "LINE")(8 . "0")(10  50.0 50.0 0.0)(11 100.0 100.0 0.0)))
(entmake e)
```