Computes and draws contour lines.

ly_contour(
fig,
z,
x = seq(0, 1, length.out = nrow(z)),
y = seq(0, 1, length.out = ncol(z)),
nlevels = 10,
levels = pretty(range(z, na.rm = TRUE), nlevels),
color = "black",
alpha = 1,
width = 1,
type = 1,
lname = NULL,
lgroup = NULL,
...
)

## Arguments

fig figure to modify a matrix containing the values to compute contour lines for locations of grid lines at which the values in image are measured (see contourLines) parameters sent to contourLines) color to use to stroke lines with - a hex code (with no alpha) or any of the 147 named CSS colors, e.g 'green', 'indigo' transparency value for the line between 0 (transparent) and 1 (opaque) stroke width in units of pixels an integer between 1 and 6 matching the lty property in par or an array of integer pixel distances that describe the on-off pattern of dashing to use layer name layer group additional parameters for fine control over line properties (see "Additional parameters" below)

 line_join how path segments should be joined together 'miter' 'round' 'bevel' line_cap how path segments should be terminated 'butt' 'round' 'square' line_dash an integer between 1 and 6 matching the lty property in par or an array of integer pixel distances that describe the on-off pattern of dashing to use line_dash_offset the distance in pixels into the line_dash that the pattern should start from

Other layer functions: ly_abline(), ly_annular_wedge(), ly_annulus(), ly_arc(), ly_bar(), ly_bezier(), ly_boxplot(), ly_crect(), ly_curve(), ly_density(), ly_hist(), ly_image_url(), ly_image(), ly_lines(), ly_map(), ly_multi_line(), ly_oval(), ly_patch(), ly_points(), ly_polygons(), ly_quadratic(), ly_quantile(), ly_ray(), ly_rect(), ly_segments(), ly_text(), ly_wedge()

## Examples

# \donttest{
p <- figure(xlim = c(0, 1), ylim = c(0, 1), title = "Volcano") %>%
ly_image(volcano) %>%
ly_contour(volcano)
p
# }