Solution 1 (Accepted):

Ok.. I 'll answer my own question. As per the suggestion count values were stored as factor. Converting them to numeric did the trick

qplot(factor(genotype),as.numeric(count),data=sampe,geom="boxplot")

Thank you all for the suggestions.

Solution 2 :

I think your problem is that your Y-axis is not actually count, R understand count as a variable. Actually you only need to group the data by genotype and than do ggplot2.

df %>% group_by(genotype)
ggplot(df) +
  geom_boxplot(mapping = aes(x=genotype, y = count))

Similar Questions : Answers:ggplot2 boxplot

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