Partition
⊆ ⊂

Partition (⊆
, ⊂
) is a dyadic function which splits its right argument into differently sized pieces as determined by the nonnegative integer left argument. This article uses ⊆
to distinguish Partition from Partitioned Enclose (which is always ⊂
), but the actual glyph used varies by dialect.
On a vector right argument, the arguments must have the same length with each element in the left argument corresponding to an element in the right argument. Partition begins a new division of its right argument whenever a left argument element is greater than its neighbour on the left (with a 0 assumed to the left of the first element):
1 1 2 2 2 2 2⊆'HiEarth'
┌──┬─────┐
│Hi│Earth│
└──┴─────┘
Right argument elements can be skipped by having their corresponding left argument element be 0:
1 1 2 2 2 0 0⊆'HiEarth'
┌──┬───┐
│Hi│Ear│
└──┴───┘
In the case where the left argument is Boolean, Partition splits its right argument on runs of 0s in the left argument, allowing a very short splitondelimiter function:
1 1 1 0 1 1 1 0 1 1 1 1⊆'How are you?'
┌───┬───┬────┐
│How│are│you?│
└───┴───┴────┘
' '(≠⊆⊢)'How are you?'
┌───┬───┬────┐
│How│are│you?│
└───┴───┴────┘
External links
Tutorials
Documentation
APL builtins [edit]  

Primitive functions  
Scalar  
Monadic  Conjugate ∙ Negate ∙ Signum ∙ Not ∙ Roll ∙ Type  
Dyadic  Add ∙ Subtract ∙ Equal to (Xnor) ∙ Not Equal to (Xor) ∙ Minimum ∙ Maximum ∙ Comparison functions  
NonScalar  
Structural  Shape ∙ Reshape ∙ Tally ∙ Depth ∙ Ravel ∙ Reverse ∙ Raze ∙ Mix ∙ Cut (K) ∙ Pair ∙ Replicate ∙ Partitioned Enclose  
Selection  Take ∙ Drop ∙ Unique ∙ Identity ∙ Select  
Selector  Interval Index ∙ Indices  
Computational  Match ∙ Not Match ∙ Nub Sieve ∙ Format ∙ Execute  
Primitive operators  Each ∙ Reverse Compose ∙ Replicate  
Quad names  
Arrays  Index origin ∙ Migration level  
Functions  
Operators  
Other  Zilde ∙ High minus ∙ Function axis 