Minimum

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Minimum (⌊), Min, or Lesser of is a dyadic scalar function which returns the smaller of its two arguments. The name "Minimum" is sometimes also used for the Minimum Reduce ⌊/, which returns the smallest element of a vector (this usage is related to the minimum of a function). Minimum is paired with Maximum, which returns the greater argument rather than the smaller, and shares the glyph ⌊ with the Floor function. It is not subject to comparison tolerance, since the result will be exactly equal to one argument, and there is no reason to choose a larger argument even if the two arguments are tolerantly equal. As a Boolean function, Minimum is identical to And.

Examples

Minimum finds the smaller of two numbers: 

      2.4 ⌊ 1.9
1.9

Together with Maximum, it can clamp an array of numbers to a range (closed interval), here from 0 to 1: 

      0 ⌈ 1 ⌊ ¯0.2 ¯0.1 0.3 0.8 1 1.3
0 0 0.3 0.8 1 1

Because the complex numbers do not form an ordered field, attempting to take the minimum with a complex argument yields a DOMAIN ERROR. 

      3 ⌊ 3j1
DOMAIN ERROR
      3⌊3J1
       ∧

Reduction

Minimum Reduce finds the smallest element in an entire vector: 

      ⌊/ 4 3 2 3 1 5 7
1

To find the index of the minimum, Index Of can be used to search for it. A shorter, but usually slower, method is to take the First of the vector's Grade. 

      {⍵⍳⌊/⍵} 4 3 2 3 1 5 7
5
      ⊃⍋ 4 3 2 3 1 5 7
5

The two solutions may differ when comparison tolerance is not zero, because Index Of uses tolerant comparison but Grade does not. The first solution will return a smaller index if an element that is tolerantly but not exactly equal to the minimum is found at that index.

External links

Documentation


APL built-ins [edit]
Primitives (Timeline) Functions
Scalar
Monadic Conjugate ∙ Negate ∙ Signum ∙ Reciprocal ∙ Magnitude ∙ Exponential ∙ Natural Logarithm ∙ Floor ∙ Ceiling ∙ Factorial ∙ Not ∙ Pi Times ∙ Roll ∙ Type ∙ Imaginary ∙ Square Root ∙ Round
Dyadic Add ∙ Subtract ∙ Times ∙ Divide ∙ Residue ∙ Power ∙ Logarithm ∙ Minimum ∙ Maximum ∙ Binomial ∙ Comparison functions ∙ Boolean functions (And, Or, Nand, Nor) ∙ GCD ∙ LCM ∙ Circular ∙ Complex ∙ Root
Non-Scalar
Structural Shape ∙ Reshape ∙ Tally ∙ Depth ∙ Ravel ∙ Enlist ∙ Table ∙ Catenate ∙ Reverse ∙ Rotate ∙ Transpose ∙ Raze ∙ Mix ∙ Split ∙ Enclose ∙ Nest ∙ Cut (K) ∙ Pair ∙ Link ∙ Partitioned Enclose ∙ Partition
Selection First ∙ Pick ∙ Take ∙ Drop ∙ Unique ∙ Identity ∙ Stop ∙ Select ∙ Replicate ∙ Expand ∙ Set functions (Intersection ∙ Union ∙ Without) ∙ Bracket indexing ∙ Index ∙ Cartesian Product ∙ Sort
Selector Index generator ∙ Grade ∙ Index Of ∙ Interval Index ∙ Indices ∙ Deal ∙ Prefix and suffix vectors
Computational Match ∙ Not Match ∙ Membership ∙ Find ∙ Nub Sieve ∙ Encode ∙ Decode ∙ Matrix Inverse ∙ Matrix Divide ∙ Format ∙ Execute ∙ Materialise ∙ Range
Operators Monadic Each ∙ Commute ∙ Constant ∙ Replicate ∙ Expand ∙ Reduce ∙ Windowed Reduce ∙ Scan ∙ Outer Product ∙ Key ∙ I-Beam ∙ Spawn ∙ Function axis ∙ Identity (Null, Ident)
Dyadic Bind ∙ Compositions (Compose, Reverse Compose, Beside, Withe, Atop, Over) ∙ Inner Product ∙ Determinant ∙ Power ∙ At ∙ Under ∙ Rank ∙ Depth ∙ Variant ∙ Stencil ∙ Cut ∙ Direct definition (operator) ∙ Identity (Lev, Dex)
Quad names Index origin ∙ Comparison tolerance ∙ Migration level ∙ Atomic vector
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