Array length

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Revision as of 18:09, 27 September 2015 by Walterpachl (talk | contribs) (→‎{{header|REXX}}: cosmetics)
Array length is a draft programming task. It is not yet considered ready to be promoted as a complete task, for reasons that should be found in its talk page.

Determine the amount of elements in an array.
As an example use an array holding the strings 'apple' and 'orange'.

See also

ALGOL 68

<lang algol68># UPB returns the upper bound of an array, LWB the lower bound # []STRING fruits = ( "apple", "orange" ); print( ( ( UPB fruits - LWB fruits ) + 1, newline ) ) # prints 2 #</lang>

EchoLisp

<lang scheme> (length '("apple" "orange")) ;; list

  → 2

(vector-length #("apple" "orange")) ;; vector

  → 2

</lang>

Haskell

<lang Haskell>-- Char -> Int length ["apple", "orange"]</lang>

JavaScript

<lang javascript>console.log(['apple', 'orange'].length);</lang>

PHP

<lang php>print count(['apple', 'orange']); // Returns 2</lang>

Python

<lang python>>>> print(len(['apple', 'orange'])) 2 >>> </lang>

REXX

<lang rexx>/* REXX ----------------------------------------------

  • The compond variable a. implements an array
  • By convention, a.0 contains the number of elements
  • ---------------------------------------------------*/

a.=0 /* initialize the "array" */ call store 'apple' Call store 'orange' Say 'There are' a.0 'elements in the array:' Do i=1 To a.0

 Say 'Element' i':' a.i
 End

Exit store: Procedure Expose a. z=a.0+1 a.z=arg(1) a.0=z Return</lang>

Output:
There are 2 elements in the array:
Element 1: apple
Element 2: orange

SQL

<lang sql>SELECT COUNT() FROM (VALUES ('apple'),('orange'));</lang>