Shiv wrote:
I am trying a simple toin coss simulation, of say 200 coin tosses. The idea
is to have a data frame like so:
    Experiment#    Number_Of_Heads
     1                   104
     2                    96
     3                    101

So I do:

 d <-data.frame(exp_num=c(1,2,3));  /* Just 3 experiments to begin with */
 d$head_ct <-sum(sample(0:1,200,repl=TRUE));

/* */ is not a valid comment in R, and you don't need ';' either :)

Just try evaluating the right hand side so that the R interpreter
prints the result.  This is just calling sample once, and therefore
you only get one number, 85 in your case.

 d;
  exp_num    head_ct
1       1        85
2       2        85
3       3        85                             /* the same scalar value is
applied to all the rows */

So I tried using "within", and "for", and making the "sum(   " as a
function, and I end up with the same...I get the same constant value.  But
what I want of course is different "samples"....

Look at ?replicate or just use ?rbinom directly

d <-data.frame(exp_num = 1:3)
d$head_ct <- rbinom(nrow(d), 200, prob = 0.5)







______________________________________________
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.

Reply via email to