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One error you may encounter when using R is:

**Error in plot.xy(xy.coords(x, y), type = type, ...) :
plot.new has not been called yet
**

This error occurs when you attempt to perform some action that requires a plot to already exist in R, yet a plot does not exist.

The following examples show how to fix this error in practice.

**Example 1: How to Fix Error with lines()**

Suppose we attempt to plot a fitted regression line in R:

#create data df frame(x=c(1, 2, 2, 3, 5, 6, 8, 8, 9, 9, 10, 11, 12, 15, 15), y=c(2, 3, 3, 4, 5, 5, 6, 7, 8, 8, 9, 10, 16, 19, 28)) #fit polynomial regression model model #define new sequence of x-values new_x #attempt to plot fitted regression line lines(new_x, predict(model, newdata = data.frame(x=new_x))) Error in plot.xy(xy.coords(x, y), type = type, ...) : plot.new has not been called yet

We receive an error because we canâ€™t use the **lines()** function without first creating a plot in R.

To fix this error, we can first create a scatterplot and then use the **lines()** function:

#create data df frame(x=c(1, 2, 2, 3, 5, 6, 8, 8, 9, 9, 10, 11, 12, 15, 15), y=c(2, 3, 3, 4, 5, 5, 6, 7, 8, 8, 9, 10, 16, 19, 28)) #fit polynomial regression model model #define new sequence of x-values new_x #create scatterplot of x vs. y values plot(y~x, data=df) #attempt to plot fitted regression line lines(new_x, predict(model, newdata = data.frame(x=new_x)))

Notice that we donâ€™t receive an error because we first used the **plot()** function before using the **lines()** function.

**Example 2: How to Fix Error with abline()**

Suppose we attempt to create a scatterplot with a straight horizontal line in R:

#create data df frame(x=c(1, 2, 2, 3, 5, 6, 8, 8, 9, 9, 10, 11, 12, 15, 15), y=c(2, 3, 3, 4, 5, 5, 6, 7, 8, 8, 9, 10, 16, 19, 28)) #attempt to add horizontal line at y=10 abline(a=10, b=0, lwd=2) Error in plot.xy(xy.coords(x, y), type = type, ...) : plot.new has not been called yet

We receive an error because we canâ€™t use the **abline()** function without first creating a plot in R.

To fix this error, we can first create a scatterplot and then use the **abline()** function:

#create data df frame(x=c(1, 2, 2, 3, 5, 6, 8, 8, 9, 9, 10, 11, 12, 15, 15), y=c(2, 3, 3, 4, 5, 5, 6, 7, 8, 8, 9, 10, 16, 19, 28)) #create scatterplot of x vs. y plot(y~x, data=df) #add horizontal line at y=10 abline(a=10, b=0, lwd=2)

Notice that we donâ€™t receive an error because we first used the **plot()** function before using the **abline()** function.

**Related:**Â How to Use abline() in R to Add Straight Lines to Plots

**Additional Resources**

The following tutorials explain how to fix other common errors in R:

How to Fix in R: Unexpected String Constant

How to Fix in R: invalid model formula in ExtractVars

How to Fix in R: argument is not numeric or logical: returning na