animation (version 2.0-0)

flip.coin: Probability in flipping coins.

Description

Probability in flipping coins. This function provides a simulation to the process of flipping coins and computes the frequencies for `heads' and `tails'.

Usage

flip.coin(faces = 2, prob, border = "white", grid = "white", 
    col = 1:2, type = "p", pch = 21, bg = "transparent", digits = 3)

Arguments

faces

an integer or a character vector. See details below.

prob

the probability vector of showing each face. If NULL, each face will be shown in the same probability.

border

The border style for the rectangles which stand for probabilities.

grid

the color for horizontal grid lines in these rectangles

col

The colors to annotate different faces of the `coin'.

type,pch,bg

See points.

digits

integer indicating the precision to be used in the annotation of frequencies in the plot

Value

• A list containing
• freq
  A vector of frequencies (simulated probabilities)
• nmax
  the total number of tosses

Details

If faces is a single integer, say 2, a sequence of integers from 1 to faces will be used to denote the faces of a coin; otherwise this character vector just gives the names of each face. When the $i$-th face shows up, a colored thin rectangle will be added to the corresponding place (the $i$-th bar), and there will be corresponding annotations for the number of tosses and frequencies. The special argument grid is for consideration of a too large number of flipping, in which case if you still draw horizontal lines in these rectangles, the rectangles will be completely covered by these lines, thus we should specify it as NA. At last the frequency for each face will be computed and shown in the header of the plot -- this shall be close to prob if ani.options('nmax') is large enough.

References

http://animation.yihui.name/prob:flipping_coins

See Also

points, sample

Examples

oopt = ani.options(interval = 0.2, nmax = ifelse(interactive(), 
    100, 2))
## a coin would stand on the table?? just kidding :)
flip.coin(faces = c("Head", "Stand", "Tail"), type = "n", 
    prob = c(0.45, 0.1, 0.45), col = c(1, 2, 4))

flip.coin(bg = "yellow")

## HTML animation page
saveHTML({
    ani.options(interval = 0.2, nmax = ifelse(interactive(), 
        100, 2))
    par(mar = c(2, 3, 2, 1.5), mgp = c(1.5, 0.5, 0))
    flip.coin(faces = c("Head", "Stand", "Tail"), type = "n", 
        prob = c(0.45, 0.1, 0.45), col = c(1, 2, 4))
}, img.name = "flip.coin", htmlfile = "flip.coin.html", ani.height = 500, 
    ani.width = 600, title = "Probability in flipping coins", 
    description = c("This animation has provided a simulation of flipping coins", 
        "which might be helpful in understanding the concept of probability."))

ani.options(oopt)