JPhrases/MathStats

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10C. Math & Stats

m0=: median=: <.@-:@# { /:~ Median of y
m1=: tc=: (+. +./ .*.~)^:_ Transitive closure of connection matrix y
c2=: ^: Apply function x y times
c3=: ^: Conditional application of x if y is 0 or 1
m4=: gamma=: !@<: Gamma function of y
d5=: beta=: *&m4 % m4@+ Beta function of x and y
d6=: pd=: ^@-@] * ^~ % !@[ Poisson distribution of states x with average number y
d7=: outof=: ! # of combs of y objects taken x at a time
d8=: ppr=: +//.@(*/) Product of polynomials x and y
m9=: -<./"1 Move rows of table y into first quadrant
m10=: npb=: p:^:_1 Number of primes before y
m11=: pto=: p:@i.@npb List of primes to y
d12=: dpr=: [: 0 2 1 3&|: */ Direct matrix product of x and y
d13=: shurp=: (0 2;3 1)&|:@(*/) Shur product of x and y
d14=: shurs=: (0 2;3 1)&|:@(+/) Shur sum of x and y
m15=: <./ .+~ Extend distance table to next leg
d16=: +./ .*. Extend a transitive binary relation
d17=: +/ .* % #@] Mean of x weighted by y
d18=: -/ .% Alternating sum of reciprocal series x%y
d19=: +/ .% Sum of reciprocal series x%y
d20=: +/ .* Matrix product
d21=: +/ .* Sum over subsets of x located by y
m22=: +/ .*~ Sum of squares of y
d23=: +/ .* Scalar (dot) product of vectors x and y
d24=: */ .^ Product over subsets of x located by y
m25=: +/@:*: Sum of squares of y
m26=: det=: -/ .* Determinant
m27=: (+/@(*:@(] - +/ % #)) % #)"1 Sample variance (dispersion) of y
m28=: %:@m27"1 Standard deviation of y
d29=: (+/@((]-+/@]%#@])^[)%#@])"1 x-th moment of y
m30=: m31"1 Mean of rows of table y
m31=: +/%# Mean of list y or columns of table y