r - Align grid() to plot ticks

Question

When adding ticks to a plot (more ticks than default), how does one get the grid() to align the grid to the ticks?

plot(1:10,las=1,xaxp  = c(0, 10, 10),xlim=c(0,10), ylim=c(0,10))
grid(lwd=2, nx=10, ny=10)

Tried changed the xlim and different numbers for the nx arg in grid (number of cells), but the grid simply doesn't line up.

Related, but doesn't answer question: Aligning grid lines in R, bReeze package

Related, and uses workaround: Align grid with ticks

Is the workaround the most efficient option?

Answer 1

You could use abline to draw grids. You can specify where the grids should be with h (for horizontal lines) and v (for vertical lines)

#Plot
plot(1:10,las=1,xaxp  = c(0, 10, 10),xlim=c(0,10), ylim=c(0,10))
#Add horizontal grid  
abline(h = c(0,2,4,6,8,10), lty = 2, col = "grey")
#Add vertical grid
abline(v = 1:10,  lty = 2, col = "grey")

Another workaround is to use axis where tck value is 1. With axis, you can specify where the grids should be with at

#Plot
plot(1:10,las=1,xaxp  = c(0, 10, 10),xlim=c(0,10), ylim=c(0,10))

#Add horizontal grid  
axis(2, at = c(0,2,4,6,8,10), tck = 1, lty = 2, col = "grey", labels = NA)

#Add vertical grid
axis(1, at = 1:10, tck = 1, lty = 2, col = "grey", labels = NA)

#Add box around plot
box()