[R] how to modify the histogram's frequencies

[(Ted Harding)]

On 27-Apr-08 16:41:58, marcelha mukim wrote:
> Hi Sarah:
> 
> Thank you very much, but my problem remains. What I want is not
> duplicate the sample, but be able to divide each frequency for
> a factor(specific for each value).For example:
> 
> Values           1      2     3    4     5
> Frequency      10   34   56   67   98
> Factor           105   50   60  150  200
> 
> Actually Im plotting: plot(Values, Frequency/Factor, type="b").
> But I dont know how to visualize the probability distribution.
> On the hand  to modify the "hist" function to include this Factor
> seems to be a daunting task.
> 
> any other advise will be welcome
> thank you
> m.

You don't need to go that far! Assuming you need to use hist()
to construct the counts in the first place, you can then modify
the $counts component of what it returns.

Here is an example using uniform random data:

  X <- 5*runif(265)

## Have a look at it:

  hist(X,breaks=5)

## Now make a histogram with class frequencies divided by the factors:

  Factor <- c(105,50,60,150,200)
  H <- hist(X,breaks=5,plot=FALSE)
  H$counts <- H$counts/Factor
  plot(H)

Is that the sort of thing you were after?

Best wishes,
Ted.

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Date: 27-Apr-08                                       Time: 19:14:39
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