Yorick (programming language)

<h2 id="features">Features</h2>
<h3>Indexing</h3>
<p>Yorick is good at manipulating elements in N-dimensional arrays conveniently with its powerful syntax.
</p><p>Several elements can be accessed all at once:
</p>
> x=[1,2,3,4,5,6];
> x
[1,2,3,4,5,6]
> x(3:6)
[3,4,5,6]
> x(3:6:2)
[3,5]
> x(6:3:-2)
[6,4]

Arbitrary elements
> x=[[1,2,3],[4,5,6]]
> x
[[1,2,3],[4,5,6]]
> x([2,1],[1,2])
[[2,1],[5,4]]
> list=where(1<x)
> list
[2,3,4,5,6]
> y=x(list)
> y
[2,3,4,5,6]

Pseudo-index
<p>Like "theading" in <a href="/facts/Perl_Data_Language/wzAaHo98">PDL</a> and "broadcasting" in <a href="/facts/Numpy/T6FnhWWD">Numpy</a>, Yorick has a mechanism to do this:
</p>
> x=[1,2,3]
> x
[1,2,3]
> y=[[1,2,3],[4,5,6]]
> y
[[1,2,3],[4,5,6]]
> y(-,)
[[[1],[2],[3]],[[4],[5],[6]]]
> x(-,)
[[1],[2],[3]]
> x(,-)
[[1,2,3]]
> x(,-)/y
[[1,1,1],[0,0,0]]
> y=[[1.,2,3],[4,5,6]]
> x(,-)/y
[[1,1,1],[0.25,0.4,0.5]]

Rubber index
<p>".." is  a rubber-index to represent zero or more dimensions of the array.
</p>
> x=[[1,2,3],[4,5,6]]
> x
[[1,2,3],[4,5,6]]
> x(..,1)
[1,2,3]
> x(1,..)
[1,4]
> x(2,..,2)
5

<p>"*" is a kind of rubber-index to reshape a slice(sub-array) of array to a vector.
</p>
> x(*)
[1,2,3,4,5,6]

Tensor multiplication
<p><a href="/facts/Tensor/pNjFo5tV">Tensor</a> multiplication is done as follows in Yorick:
</p>
P(,+, )*Q(, +)

<p>means 
  
    
      
        
          ∑
          
            j
            =
            1
          
          
            j
            =
            N
          
        
        
          
            P
            
              i
              j
              k
              l
            
          
          
            Q
            
              m
              n
              j
            
          
        
      
    
    {\displaystyle \sum _{j=1}^{j=N}{P_{ijkl}Q_{mnj}}}

</p>
> x=[[1,2,3],[4,5,6]]
> x
[[1,2,3],[4,5,6]]
> y=[[7,8],[9,10],[11,12]]
> x(,+)*y(+,)
[[39,54,69],[49,68,87],[59,82,105]]
> x(+,)*y(,+)
[[58,139],[64,154]]

<h2 id="external-links">External links</h2>
<ul><li><a href="http://www.linuxjournal.com/article/2184">Linux Journal Review</a></li>
<li><a href="https://web.archive.org/web/20170102091157/http://www.jeh-tech.com/yorick.html">Yorick tutorial on JehTech</a></li></ul>

Yorick (programming language) open-in-new

Yorick (programming language)