Question

I like to produce my own grid lines when plotting so I can control tick marks, etc. and I am struggling with this with the ‘hist’ plotting routine.

    hist(WindSpeed, breaks=c(0:31), freq=TRUE, col="blue", xaxt="n", yaxt="n", xlab="Wind Speed (m/s)",main="Foo", cex.main=1.5, cex.axis=1, cex.lab=1, tck=1, font.lab=2)
    axis(1, tck=1, ,col.ticks="light gray")
    axis(1, tck=-0.015, col.ticks="black")
    axis(2, tck=1, col.ticks="light gray", lwd.ticks="1")
    axis(2, tck=-0.015)
    minor.tick(nx=5, ny=2, tick.ratio=0.5)
    box()

Plot:

I have then just been able to use the ‘lines’ or ‘points’ command to replot the data over top for other types of plots, but with the histogram its not so easy.

Any help would be great.

I added my code below and image based upon John’s response…

I added my code below and image based upon John’s response…

hist(WindSpeed, breaks=30, freq=TRUE, col="blue", xaxt="n", yaxt="n", xlab="Wind Speed (m/s)",main="Foo", cex.main=1.5, cex.axis=1, cex.lab=1, font.lab=2)
axis(1, tck=1, col.ticks="light gray")
axis(1, tck=-0.015, col.ticks="black")
axis(2, tck=1, col.ticks="light gray", lwd.ticks="1")
axis(2, tck=-0.015)
minor.tick(nx=5, ny=2, tick.ratio=0.5)
box()
hist(WindSpeed, add=TRUE, breaks=30, freq=TRUE, col="blue", xaxt="n", yaxt="n", xlab="Wind Speed (m/s)", main="Foo", cex.main=1.5, cex.axis=1, cex.lab=1, font.lab=2)

Answer 1

This is relatively easy.

Generate the histogram but don’t plot it.

h <- hist(y, plot = FALSE)

Now generate your base plot… I’ve added some features to make it look more like a standard historgram

plot(h$mids, h$counts, ylim = c(0, max(h$counts)), xlim = range(h$mids)*1.1, 
    type = 'n', bty = 'n', xlab = 'y', ylab = 'Counts', main = 'Histogram of y')

add your grid

grid()

add your histogram

hist(y, add = TRUE)

Or, as I discovered through this process… you can do it even easier

hist(y)
grid()
hist(y, add = TRUE, col = 'white')

This last method is just redrawing the histogram over the grid.