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Task/Arrays/QB64/arrays.qb64

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+'Task
+'Show basic array syntax in your language.
+
+'Basically, create an array, assign a value to sit, and retrieve an element   (if available, show both fixed-length arrays and dynamic arrays, pushing a value into it).
+Rem  DECLARATION PART
+
+Rem QB64/QuickBasic/Qbasic array examples
+'-----------
+MyArray%(10) = 11 ' it creates an array integer of 11 elements  from 0 to 11
+Dim MyArray2%(0 To 10) ' it is equal to the previous line of code, it is its explicit way
+
+'--------------
+Option Base 1 ' from here all arrays have as default as index of first item 1
+MyArray3%(10) = 14 'it creates array from 1 to 14
+
+Dim Myarray4%(1 To 14) ' it is equal to the 2 previous lines of code
+
+'-----------------
+Dim Shared myArray$(-12 To 12) ' it creates a string array with 25 elements and SHARED makes it global array
+
+'---------------------
+'$dynamic
+Dim MyArray1!(1 To 4) ' these two lines of code create a resizable array
+
+ReDim myArray2!(1 To 4) ' it does the same of the 2 previous lines of code
+
+'-------------------------
+' alternatively at the place of suffix ! or $ or % or # or &
+' you can use the explicit way  "DIM namearray (start to end) AS TypeOfVariable"
+Dim MyIntegerArray(1 To 10) As Integer
+Dim MyStringArray(1 To 10) As String
+Dim MySingleArray(1 To 10) As Single
+Dim MyLongArray(1 To 10) As Long
+Dim MyDoubleArray(1 To 10) As Double
+
+'---------------------------
+'it is possible defining an User Data Type and creating an array with that type
+Type MyType
+    Name As String * 8 ' a fixed lenght string variable
+    ID As Integer
+    Position As Single
+End Type
+
+Dim Lists(1 To 10) As MyType
+ReDim WhoIs(-19 To 10) As MyType
+
+
+'------------------------------
+' Number of dimensions of an array: QuickBasic vs QB64
+' an array can have from 1 to until 60 dimensions in QuickBasic
+' an array can have from 1 to RAM dimension of your machine
+' you must think that in the dayly practice is rare to use more than 3 dimensions
+Dim Calendar%(1 To 31, 1 To 56, 1 To 12) ' array calendar with days, week, mounths
+ReDim Time(1 To 60, 1 To 60, 1 To 24) As Integer ' array Time with seconds, minutes and hours
+
+Rem  ONLY QB64 arrays
+'--------
+' QB64 introduces more TypeOfVariable all of them associated to a suffix
+' so you can declare also these kind of data
+' _BIT  or `, _BYTE or %%, _INTEGER64 or &&, _FLOAT or ##, OFFSET or %&, _MEM (no suffix)
+Dim MyByteArray%%(1 To 4)
+Dim MyByteArray2(1 To 4) As _Byte
+' are the same declaration of the array
+
+'----------------
+'QB64 lets you to use an alternative way to declare variables and array
+'using the following syntax:   DIM / REDIM  AS Type of data  Array1, Array2, Array3"
+ReDim As _MEM Mem1(1 To 5), Mem2(6 To 10)
+Dim As _Unsigned _Byte UByte(-3 To 25), Ubyte2(100 To 200)
+
+
+Rem QB64 / QB PDS (7.1) arrays
+ReDim MyPreservedArray(1 To 5) As Integer ' it creates a dynamic array
+ReDim _Preserve MyPreservedArray(-3 To 100) As Integer ' it changes limit of dimension of array
+
+Rem ASSIGNING PART
+' at declaration point each array is initializated: 0 for digit arrays, "" for string arrays
+' in the UDT arrays each variable is initializated following its type
+
+
+' all types of array can be accessed using the index of item choice to change
+' in the UDT array each item of UDT is reached using the "." while the item of array needs the index
+Print MyPreservedArray(2)
+MyPreservedArray(2) = 12345
+Print MyPreservedArray(2)
+
+Print WhoIs(-10).Name
+WhoIs(-10).Name = "QB64"
+Print WhoIs(-10).Name
+WhoIs(10).Name = WhoIs(-10).Name
+Print WhoIs(10).Name
+
+Rem RETRIEVE AN ELEMENT
+' basically the coder must use a loop for scanning the whole array for that value choosen
+
+'-----------------
+' static array
+MySingleArray(4) = 4
+MySingleArray(8) = 8
+For n = 1 To 10
+    If MySingleArray(n) > 0 Then Print MySingleArray(n)
+Next
+
+
+'dynamic array
+
+WhoIs(-10).Name = "QB64"
+WhoIs(10).Name = "C#"
+WhoIs(1).Name = "Java"
+Print WhoIs(-10).Name, WhoIs(10).Name, WhoIs(1).Name
+ReDim _Preserve WhoIs(-10 To 19) As MyType
+Print
+Print WhoIs(-10).Name, WhoIs(10).Name, WhoIs(1).Name
+Print WhoIs(-1).Name, WhoIs(19).Name, WhoIs(10).Name