### Important parameters

**pch**: plotting symbol**lty**: line type**lwd**: line width**col**: plotting color**las**: orientation of axis labels**bg**: background color**mar**: margin size**oma**: outer margin size**mfrow**: number of plots per row, column. Plots filled in row-wise.**mfcol**: number of plots per row, column. Plots filled in column-wise.

### Import functions

**plot**: make scatterplot**lines**: add lines to plot**points**: add points to plot**text**: add text**title**: add title to axes or plot**mtext**: add margin text**axis**: add axis tick/labels

### Example 1

```
x <- rnorm(100)
y <- rnorm(100)
plot(x, y, pch = 21, mar = c(4, 4, 2, 2), col = "red", bg = "black", xlim = c(-3,
3), ylim = c(-3, 3))
fit <- lm(y ~ x)
abline(fit, lwd = 3, col = "blue")
title("My plot")
text(-2, -2, "My Label")
legend("topleft", legend = "Data", pch = 21, pt.bg = "black", col = "red")
```

### Example 2

To use multiple plots per page, give a `mfrow`

argument to plot. Then the plots will be filled from left to right across the rows. (Specifying `mfcol`

will fill in plots from top to bottom down the
columns. )

```
z <- rpois(100, 2)
plot.new()
par(mfrow = c(2, 2))
par(mar = c(3, 3, 2, 2))
plot(x, y, pch = 20, main = "plot 1")
plot(x, z, pch = 19, main = "plot 2")
plot(y, z, pch = 1, main = "plot 3")
```

### Example 3

The `points`

function is useful for adding points to a plot for different groups.

```
plot.new()
x <- rnorm(100)
y <- x + rnorm(100)
g <- gl(2, 50, labels = c("Male", "Female"))
str(g)
```

```
## Factor w/ 2 levels "Male","Female": 1 1 1 1 1 1 1 1 1 1 ...
```

```
plot(x, y, type = "n") # Draws no points
points(x[g == "Male"], y[g == "Male"], col = "blue", pch = 1)
points(x[g == "Female"], y[g == "Female"], col = "red", pch = 19)
legend("topleft", c("Male", "Female"), col = c("blue", "red"), pch = c(1, 19))
```

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