barplot usage

Hi,

I'm trying to make a barplot with the following dataframe, with information on
relative frequency per sediment type (ST) for some species:

Species  ST1  ST2  ST3
SP_A     10   60    30
...


At x-axis are (should be ...) the species names and at y-axis the frequency per
sediment, in stacked bars.

I tried to use barplot command but with no results. Could anyone help me on this?

Thanks in advance,

Samantha

You could use something like the following (presuming that your data is
a data frame called 'df'):

  barplot(t(df[2:4]), names.arg = as.character(df$Species))

Note that the row values that you have (excluding the Species name) need
to be rotated 90 degrees as follows:

t(df[2:4])

1 ...
ST1 10 ...
ST2 60 ...
ST3 30 ...

In this case, each column represents the segments of each stacked bar
(or if you set 'beside = TRUE', the individual bars in a group of bars)

Then the labels below each bar in the plot come from the df$Species
column. I used as.character(df$Species) presuming that this column might
be a factor. If not, you can eliminate the use of as.character() here.

HTH,

Marc Schwartz