Less than: Difference between revisions

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== Boolean function ==
{{Main|Boolean function}}
When used as a [[Boolean function]] (that is, with argument consisting entirely of 0s and 1s), it represents [[wikipedia:converse nonimplication|converse nonimplication]]:
{|class=wikitable
!<source lang=apl inline><</source>!!<source lang=apl inline>0</source>!!<source lang=apl inline>1</source>
|-
!<source lang=apl inline>0</source>
|<source lang=apl inline>0</source>||<source lang=apl inline>0</source>
|-
!<source lang=apl inline>0</source>
|<source lang=apl inline>1</source>||<source lang=apl inline>0</source>
|}
In the context of logic, it can be read as ''isn't, as opposed to''.
== External links ==
== External links ==



Revision as of 08:21, 29 March 2020

Main article: Comparison function
<

Less than (<) is a comparison function which tests whether the left argument is tolerantly less than and not equal to the right argument, returning 1 if this is the case and 0 otherwise. It is the negation of Greater than or Equal to ().

Less than is also notable as a Boolean function, in which case it returns 1 only if the left argument is 0 and the right argument is 1 (the same as Residue). In particular, Less-than Scan on a Boolean vector returns a vector which indicates the position of the first 1 in the argument, if any:

      <\ 0 0 1 0 0 0 1 0
0 0 1 0 0 0 0 0

Boolean function

Main article: Boolean function

When used as a Boolean function (that is, with argument consisting entirely of 0s and 1s), it represents converse nonimplication:

< 0 1
0 0 0
0 1 0

In the context of logic, it can be read as isn't, as opposed to.

External links

Documentation


APL built-ins [edit]
Primitives (Timeline) Functions
Scalar
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Dyadic AddSubtractTimesDivideResiduePowerLogarithmMinimumMaximumBinomialComparison functionsBoolean functions (And, Or, Nand, Nor) ∙ GCDLCMCircularComplexRoot
Non-Scalar
Structural ShapeReshapeTallyDepthRavelEnlistTableCatenateReverseRotateTransposeRazeMixSplitEncloseNestCut (K)PairLinkPartitioned EnclosePartition
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Dyadic BindCompositions (Compose, Reverse Compose, Beside, Withe, Atop, Over) ∙ Inner ProductDeterminantPowerAtUnderRankDepthVariantStencilCutDirect definition (operator)
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