m0=: A=: # %~ +/ | Arithmetic mean |
m1=: G=: # %: */ | Geometric mean |
m2=: H=: A&.(%"_) | Harmonic mean |
m3=: C=: {.@((G,A)^:_) | Common mean (de Kerf [2]) |
m4=: A&(^&3) | Mean of cubes |
a5=: (^&) (A&) | Generalized x-mean |
m6=: m4 -: 3 a5 | Tautology |
a7=: (^&) (A&.) | L-x norm |
m8=: (^&3)@(3 a7) -: (3 a5) | Tautology |
v9=: MA=: A\ | x-period moving average of y |
m10=: +/\ -: +/\.&.|. | Tautology: invariance under reverse |
m11=: +/\. -: +/\ &.|. | Tautology: invariance under reverse |
m12=: +/\^:(i.`($&1)) | Figurate numbers |
m13=: 1: #. ] | Sum; +/"1 |
m14=: +/&.(*:"_)@:+."0 | Magnitude | |
m15=: - |.!.0 | .+/\^:_1 |
d16=: psum=: ([:+/ [ ^~ i.@])"0 | Sum of powers of integers; 2 sum 7 |
m17=: 0&psum -: [ | Tautology: +/(i.n)^0 |
m18=: 1&psum -: 2&! | Tautology: +/(i.n)^1 |
m19=: 2&psum -: 0 1r6 _1r2 1r3&p. | Tautology: +/(i.n)^2 |
m20=: [ (psum %. ^/~@]) i.@(2&+) | Polynomial coeff. of +/(i.n)^k |