[R] extract descriptive stats for categorial data from dataframe

[Jim Lemon]

On Tue, 5 Aug 2014 11:36:36 AM Alain D. wrote:
> Dear R-List,
> 
> I want to have descriptive stats in a special form and cannot figure 
out a
> nice solution.
> 
> df<-
as.data.frame(cbind(i1=rep("+"),i2=rep("+",10),i3=rep("-",10),i4=c(rep("
> 
-",2),"0",rep("-",7)),i5=rep("+",10),i6=c(rep("-",9),"+"),i7=c(rep("+",4),"0
> 
",rep("+",5)),i8=c(rep(0,4),rep("+",3),"-","+","-"),i9=c(rep("+",5),"-",rep(
> "+",2),rep(0,2))))
> 
> now I want the categories as var labels arranged in cols with IDs as 
first
> col and then frequencies for each category. Something like this:
> 
> var   +   -    0
> i1    10  0    0
> i2    10  0    0
> i3     0 10    0
> i4     0  9    1
> i5    10  0    0
> i6     1  9    0
> i7     9  0    1
> i8     4  2    4
> i9     7  1    2
> 
> I tried different combinations of
> 
> freq<-as.data.frame(df<-lapply(df,table))
> 
> but was not very successful.
> 
> I would be very thankful for an easy solution which is probably to 
obvious
> for me to spot.
> 
Hi Alain,
You can get pretty much what you want if your variables are all factors 
with the same levels like this:

varlevels<-c("+","-","0","1")
df<-data.frame(
 i1=factor(rep("+",10),levels=varlevels),
 i2=factor(rep("+",10),levels=varlevels),
 i3=factor(rep("-",10),levels=varlevels),
 i4=factor(c(rep("-",2),"0",rep("-",7)),levels=varlevels),
 i5=factor(rep("+",10),levels=varlevels),
 i6=factor(c(rep("-",9),"+"),levels=varlevels),
 i7=factor(c(rep("+",4),"0",rep("+",5)),levels=varlevels),
 i8=factor(c(rep(0,4),rep("+",3),"-","+","-"),levels=varlevels),
 i9=factor(c(rep("+",5),"-",rep("+",2),rep(0,2)),levels=varlevels))
library(prettyR)
describe(df,horizontal=TRUE,fname.space=10)

Jim