COR = corrf(F, DIM) returns the correlation function of the scalar
field F along the dimension DIM (with DIM=1, 2, or 'x','y', for
correlation along the 'X' or 'Y' direction). If F is an array of
scalar fields, COR returns the average of the correlation functions of
each field.
COR is a structure which contains the following fields:
r: separation length
f: correlation function
unitr: unit of separation length
unitf: unit of correlation function
namef: name of correlation function
isinf: integral scale, computed as the integral of f up to infty
r5: scale at which f(r5)=0 (linearly interpolated)
is5: integral scale, computed as the integral of f up to r5
r2, is2, r1, is1: idem as r5, is5, for crossovers at 0.2 and 0.1
COR = corrf(F, DIM, 'norm') normalizes the correlation function.
Note that corrf(vec2scal(V,'ux'),'x') and corrf(vec2scal(V,'uy'),'y')
are the longitudinal velocity correlation functions, and
corrf(vec2scal(V,'ux'),'y') and corrf(vec2scal(V,'uy'),'x') are the
transverse ones.
If no output argument, the correlation function is plotted.
Example
v = loadvec('B00001.VEC');
cor = corrf(vec2scal(v,'vx'),'x');
plot(cor.r, cor.f, 'o-');
See Also
vec2scal, statf, histf, vsf.