19.6 Histograms

Simple histogram on one sample (using the df2 data frame):

ggplot(data=df1, mapping=aes(x=sample1)) + geom_histogram()

Histogram on more samples (using df_long):

ggplot(data=df_long, mapping=aes(x=value)) + geom_histogram()

Split the data per sample (“variable” column that represents here the samples):

ggplot(data=df_long, mapping=aes(x=value, fill=variable)) + geom_histogram()

By default, the histograms are stacked: change to position dodge (side by side):

phist <- ggplot(data=df_long, mapping=aes(x=value, fill=variable)) + 
    geom_histogram(position='dodge')