stdevf - standard deviation
This function computes the standard deviation of the values of a vector or matrix x , each of them counted with a frequency given by the corresponding values of the integer vector or matrix fre who has the same type of x .
For a vector or matrix x , s=stdevf(x,fre) (or s=stdevf(x,fre,'*') returns in scalar s the standard deviation of all the entries of x , each value counted with the multiplicity indicated by the corresponding value of fre .
s=stdevf(x,fre,'r') (or, equivalently, s=stdevf(x,fre,1) ) returns in each entry of the row vector s of type 1xsize(x,'c') the standard deviation of each column of x , each value counted with the multiplicity indicated by the corresponding value of fre .
s=stdevf(x,fre,'c') (or, equivalently, s=stdevf(x,fre,2) ) returns in each entry of the column vector s of type size(x,'c')x1 the standard deviation of each row of x , each value counted with the multiplicity indicated by the corresponding value of fre .
x=[0.2113249 0.0002211 0.6653811;0.7560439 0.9546254 0.6283918] fre=[1 2 3;3 4 3] m=stdevf(x,fre) m=stdevf(x,fre,'r') m=stdevf(x,fre,'c')
Carlos Klimann
Wonacott, T.H. & Wonacott, R.J.; Introductory Statistics, fifth edition, J.Wiley & Sons, 1990.