Core Features

Language implementation and core functionality of XDL.

Language Features

XDL provides a complete implementation of IDL-compatible language features:

• Variables and Expressions - Dynamic typing, numeric and string variables
• Control Flow - IF/THEN/ELSE, FOR, WHILE, FOREACH loops
• Functions and Procedures - User-defined and built-in functions
• Array Operations - N-dimensional arrays with efficient indexing
• Structures - Complex data types
• Keyword Arguments - Named function parameters

Data Types

XDL supports all IDL/GDL data types:

Type	Description	Example
BYTE	8-bit unsigned integer	255B
INT	16-bit signed integer	32767
LONG	32-bit signed integer	2147483647L
FLOAT	32-bit floating point	3.14
DOUBLE	64-bit floating point	3.14D
COMPLEX	Complex numbers	COMPLEX(1, 2)
STRING	Character strings	‘Hello’

Array Operations

Powerful array manipulation:

; Create arrays
a = findgen(100)
b = fltarr(10, 10)

; Array indexing
subset = a[0:49]
row = b[*, 0]

; Array operations
c = a + b
d = transpose(a)
e = reform(a, 10, 10)

Control Flow

Complete control flow support:

; IF/THEN/ELSE
if condition then begin
  ; statements
endif else begin
  ; statements
endelse

; FOR loops
for i = 0, 99 do begin
  ; statements
endfor

; WHILE loops
while condition do begin
  ; statements
endwhile

Functions

Built-in and user-defined functions:

; Mathematical functions
y = sin(x)
z = exp(log(x))

; Array functions
mean_val = mean(array)
sorted = sort(array)

; User-defined functions
function square, x
  return, x * x
end