brushedPoints()
returns rows from a data frame which are under a brush.
nearPoints()
returns rows from a data frame which are near a click, hover,
or double-click. Alternatively, set allRows = TRUE
to return all rows from
the input data with an additional column selected_
that indicates which
rows of the would be selected.
brushedPoints(
df,
brush,
xvar = NULL,
yvar = NULL,
panelvar1 = NULL,
panelvar2 = NULL,
allRows = FALSE
)
nearPoints(
df,
coordinfo,
xvar = NULL,
yvar = NULL,
panelvar1 = NULL,
panelvar2 = NULL,
threshold = 5,
maxpoints = NULL,
addDist = FALSE,
allRows = FALSE
)
A data frame from which to select rows.
The data from a brush or click/dblclick/hover event
e.g. input$plot_brush
, input$plot_click
.
A string giving the name of the variable on the x or y axis.
These are only required for base graphics, and must be the name of
a column in df
.
A string giving the name of a panel variable. For expert use only; in most cases these will be automatically derived from the ggplot2 spec.
If FALSE
(the default) return a data frame containing
the selected rows. If TRUE
, the input data frame will have a new
column, selected_
, which indicates whether the row was selected or not.
A maximum distance (in pixels) to the pointer location.
Rows in the data frame will be selected if the distance to the pointer is
less than threshold
.
Maximum number of rows to return. If NULL
(the default),
will return all rows within the threshold distance.
If TRUE, add a column named dist_
that contains the
distance from the coordinate to the point, in pixels. When no pointer
event has yet occurred, the value of dist_
will be NA
.
A data frame based on df
, containing the observations selected by the
brush or near the click event. For nearPoints()
, the rows will be sorted
by distance to the event.
If allRows = TRUE
, then all rows will returned, along with a new
selected_
column that indicates whether or not the point was selected.
The output from nearPoints()
will no longer be sorted, but you can
set addDist = TRUE
to get an additional column that gives the pixel
distance to the pointer.
For plots created with ggplot2, it is not necessary to specify the
column names to xvar
, yvar
, panelvar1
, and panelvar2
as that
information can be automatically derived from the plot specification.
Note, however, that this will not work if you use a computed column, like
aes(speed/2, dist))
. Instead, we recommend that you modify the data
first, and then make the plot with "raw" columns in the modified data.
If x or y column is a factor, then it will be coerced to an integer vector. If it is a character vector, then it will be coerced to a factor and then integer vector. This means that the brush will be considered to cover a given character/factor value when it covers the center value.
If the brush is operating in just the x or y directions (e.g., with
brushOpts(direction = "x")
, then this function will filter out points
using just the x or y variable, whichever is appropriate.
plotOutput()
for example usage.
if (FALSE) { # \dontrun{
# Note that in practice, these examples would need to go in reactives
# or observers.
# This would select all points within 5 pixels of the click
nearPoints(mtcars, input$plot_click)
# Select just the nearest point within 10 pixels of the click
nearPoints(mtcars, input$plot_click, threshold = 10, maxpoints = 1)
} # }