data(E2grades)
g = E2grades
B = boxplot(g[g>1], plot=FALSE)
divs = c(min(g), B$stats[1:4] + diff(B$stats)/2, max(g) )
### get(getOption("device"))(width = 12, height = 7)
D1 = do.grades(g, divs=divs, cut = 15, tit="GEOL 105 Exam 1")
jist(D1$hist, D1$grades, D1$lett, col='purple')
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