[R] Flip heatmap color range in base R?

[Serena De Stefani]

I am building a simple heat map in base R.
This is my matrix:

    stleft = matrix(
         c(0,5,5,2,6,8,4,6,9),
         nrow=3,
         ncol=3)
    colnames(stleft) <- c("Narrow","Wide", "Wider")
    rownames(stleft) <- c("Person", "Object","Bare")
    stleft


The matrix looks like this:

    > stleft
           Narrow Wide Wider
    Person      0    2     4
    Object      5    6     6
    Bare        5    8     9

To build the heat map I simply run:

    heatmap(stleft, Colv = NA, Rowv = NA, scale = "none")

You may see it here: https://i.stack.imgur.com/KCblOm.png

As you can see the "0" (corresponding to the narrow/person cell) appears as
a deep red while the "9" (corresponding to the wider/bare cell) appears as
light yellow.

- How can I "flip" this range so that the "0" appears in a light color and
the "9" in a deep color?

I have also three other questions (less important at the moment):

- How can I have a heat map with the same row/column order as my original
matrix?

- Why is the image truncated? It appears truncated in the RStudio plot
panel and it is saved truncated. I have tried to enlarge the plot panel in
R Studio to no avail.

- How can I insert numbers in the cells?

	[[alternative HTML version deleted]]