lassoPoints {iSEE} | R Documentation |
Identify the rows of a data.frame lying within a closed lasso polygon, analogous to brushedPoints
.
lassoPoints(df, lasso)
df |
A data.frame from which to select rows. |
lasso |
A list containing data from a lasso. |
This function uses in.out
from the mgcv package to identify points within a polygon.
This involves a boundary crossing algorithm that may not be robust in the presence of complex polygons with intersecting edges.
A subset of rows from df
with coordinates lying within lasso
.
Aaron Lun
lasso <- list(coord=rbind(c(0, 0), c(0.5, 0), c(0, 0.5), c(0, 0)), closed=TRUE, mapping=list(x="X", y="Y")) values <- data.frame(X=runif(100), Y=runif(100), row.names=sprintf("VALUE_%i", seq_len(100))) lassoPoints(values, lasso) # With faceting information: lasso <- list(coord=rbind(c(0, 0), c(0.5, 0), c(0, 0.5), c(0, 0)), panelvar1="A", panelvar2="B", closed=TRUE, mapping=list(x="X", y="Y", panelvar1="FacetRow", panelvar2="FacetColumn")) values <- data.frame(X=runif(100), Y=runif(100), FacetRow=sample(LETTERS[1:2], 100, replace=TRUE), FacetColumn=sample(LETTERS[1:4], 100, replace=TRUE), row.names=sprintf("VALUE_%i", seq_len(100))) lassoPoints(values, lasso)