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Noncentral F random numbers


R = ncfrnd(NU1,NU2,DELTA)
R = ncfrnd(NU1,NU2,DELTA,m,n,...)
R = ncfrnd(NU1,NU2,DELTA,[m,n,...])


R = ncfrnd(NU1,NU2,DELTA) returns a matrix of random numbers chosen from the noncentral F distribution with corresponding numerator degrees of freedom in NU1, denominator degrees of freedom in NU2, and positive noncentrality parameters in DELTA. NU1, NU2, and DELTA can be vectors, matrices, or multidimensional arrays that have the same size, which is also the size of R. A scalar input for NU1, NU2, or DELTA is expanded to a constant matrix with the same dimensions as the other inputs.

R = ncfrnd(NU1,NU2,DELTA,m,n,...) or R = ncfrnd(NU1,NU2,DELTA,[m,n,...]) generates an m-by-n-by-... array. The NU1, NU2, DELTA parameters can each be scalars or arrays of the same size as R.


Compute six random numbers from a noncentral F distribution with 10 numerator degrees of freedom, 100 denominator degrees of freedom and a noncentrality parameter, δ, of 4.0. Compare this to the F distribution with the same degrees of freedom.

r = ncfrnd(10,100,4,1,6)
r =
  2.5995  0.8824  0.8220  1.4485  1.4415  1.4864

r1 = frnd(10,100,1,6)
r1 =
  0.9826  0.5911  1.0967  0.9681  2.0096  0.6598


[1] Johnson, N., and S. Kotz. Distributions in Statistics: Continuous Univariate Distributions-2. Hoboken, NJ: John Wiley & Sons, Inc., 1970, pp. 189–200.

Extended Capabilities

Introduced before R2006a