Command: Take

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Name:
 Take - extract element sequences from a container
Synopsis:
 array  n Take                  return the first n elements
 array -n Take                  return the last n elements
 array [n1 n2] Take             return elements n1 through n2
 array [n1 n2 s] Take           return elements n1 through n2 in steps of s
 array [[seq1]...[seqn]] Take   return a nested list in which elements
                                specified by seqi are taken at level i in list.

Operations are the same on strings.
The implementation of Take uses the command container to abstract
the container type.

Note that Take handles indices ranging from -N to N where 
    N is the length of the original container and asking for index 0 
    will return an empty array.

If the specified indices do not exist in the container, Take throws a RangeCheck error.

If n2 < n1, Take returns an empty container.


Examples:
 [4 9 -7 3 2 11] 2 Take    --> [4 9]
 [4 9 -7 3 2 11] -2 Take   --> [2 11]
 [1 2 3 4 5] [-2] Take     --> 4
 [1 2 3 4 5] [1 -2] Take   --> [1 2 3 4]
 [1 2 3 4 5] [1 -2 2] Take --> [1 3]
 [1 2 3 4 5] [1 -1 2] Take --> [1 3 5]
% [1 2 3 4 5] [1 6] Take    --> [Error]: RangeCheck 
 (HAL) {1 add} Map     --> (IBM)
 (HAL) 2 Take          --> (HA)
 (HAL) -2 Take         --> (AL)
 (HALLO) [-2] Take     --> 76
 (HALLO) [1 -2] Take   --> (HALL)
 (HALLO) [1 -2 2] Take --> (HL)
 (HALLO) [1 -1 2] Take --> (HLO)

Author:
 Diesmann
Bugs:
 The scheme for a list of sequences is not fully consistent with Mathematica.
 See Drop for a more advanced implementation.
References:
   [1] The Mathematica Book V4.0 "Take"
SeeAlso:Drop Part MathematicaToSliIndex getinterval get
Source:
 /home/abuild/rpmbuild/BUILD/nest-2.4.1/lib/sli/mathematica.sli

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