Generate Dummy Points to Enforce Symmetric Facet Axes

Creates invisible points with x = y at the min/max range per facet to force ggplot to use symmetric x/y limits within each facet when scales are free.

Usage

generate_symmetric_dummy_points(df, facet_var, x_col, y_col)

Arguments

df

Data frame containing the plotted data.

facet_var

Character; name of the facet column in df.

x_col

Character; name of the x column in df.

y_col

Character; name of the y column in df.

Value

Data frame with columns facet_var, Observed, Simulated (using x_col and y_col names) containing min/max dummy points.

Details

The output includes two points per facet (min and max). These points can be added with geom_blank() to enforce consistent axis limits without affecting the visible data.

Examples

df <- data.frame(
  variable = c("precip", "precip", "temp", "temp"),
  Observed = c(1, 5, 10, 12),
  Simulated = c(0.5, 6, 9, 13)
)
generate_symmetric_dummy_points(df, "variable", "Observed", "Simulated")
#> # A tibble: 4 × 3
#>   variable Observed Simulated
#>   <chr>       <dbl>     <dbl>
#> 1 precip        0.5       0.5
#> 2 temp          9         9  
#> 3 precip        6         6  
#> 4 temp         13        13