COMTE Guillaume
2006-Aug-16 15:34 UTC
[R] Strange behavior with "hist" function filled with breaks and freq attribute
Hy all, I give example code : connexions_jours<-c(1,1,1,1,1,1,1,1,2,2,2,2,2,2,2,2,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,5,5,5,5,5,5,6,6,7,7,7,7,7,7,7,7,8,8,8,12,15,19) pas_de_groupe<-1 hist(connexions_jours,col="red",xlab="Répartition du nombre de connexions par jours (sans break)",main="",ylab="",freq=FALSE) hist(connexions_jours,breaks=(max(connexions_jours)/pas_de_groupe),col="red",xlab="Répartition du nombre de connexions par jours",main="",ylab="",freq=FALSE) pas_de_groupe<-5 hist(connexions_jours,breaks=(max(connexions_jours)/pas_de_groupe),col="red",xlab="Répartition du nombre de connexions par jours",main="",ylab="",freq=FALSE) As in the R help for ?hist i have : freq: logical; if 'TRUE', the histogram graphic is a representation of frequencies, the 'counts' component of the result; if 'FALSE', _relative_ frequencies ("probabilities"), component 'density', are plotted. Defaults to 'TRUE' _iff_ 'breaks' are equidistant (and 'probability' is not specified). So i'm plotting 3 graphs of probabilities, but because of the breaks the « y » values seems to be broken as if i have to multiplicate the values shown by the break range to have the real percent. So i'm wondering why it doesn't show the sum of the probability instead of the average for each values grouped. Did someone see where i'm wrong? I'll have a look to barplot, to see if it can handle it, but i still find that strange for hist... Thks all COMTE Guillaume [[alternative HTML version deleted]]