更改图

Question

如果我有一组数据，我会绘制它，例如：

data=rnorm(100,1,2)
x=1:100
plot(x,data,type="l")

如何将某些点更改为其他颜色？如：

coloured=c(2,3,4,5,43,24,25,56,78,80)

我希望coloured点，红色，如果可能的话，2,3,4和5之间的线为红色，因为它们是连续的。

Answer 1

points和lines之类的内容可能会有所帮助：

#your data
data=rnorm(100,1,2)
x=1:100
plot(x,data,type="l")
coloured=c(2,3,4,5,43,24,25,56,78,80)

#coloured points
points(coloured, data[coloured], col='red')

#coloured lines
lines(c(2,3,4,5), data[c(2,3,4,5)], col='red')

输出：

Answer 2

正如@LyzandeR所提到的，你可以使用points在你的情节上绘制红点。

points(coloured, data[coloured], col="red", pch=19)

如果你想让红线少一些手动，你可以检查连续红点的位置，并将所有位线之间用红色（即点2,3,4,5之间）在你的例子中的点24和25之间）：

# get insight into the sequence/numbers of coloured values with rle
# rle on the diff values will tell you were the diff is 1 and how many there are "in a row"
cons_col <- rle(diff(coloured)) 
# get the indices of the consecutive values in cons_col
ind_cons <- which(cons_col$values==1)    
# get the numbers of consecutive values
nb_cons <- cons_col$lengths[cons_col$values==1]
# compute the cumulative lengths for the indices
cum_ind <- c(1, cumsum(cons_col$lengths)+1)

# now draw the lines:
sapply(seq(length(ind_cons)), 
       function(i) {
          ind1 <- cum_ind[ind_cons[i]]
          ind2 <- cum_ind[ind_cons[i]] + nb_cons[i]
          lines(coloured[ind1:ind2], data[coloured[ind1:ind2]], col="red")
       })