R: scattermore

scattermore {scattermore} | R Documentation

## scattermore

### Description

Convert points to raster scatterplot rather quickly.

### Usage

    scattermore(
      xy,
      size = c(512, 512),
      xlim = c(min(xy[, 1]), max(xy[, 1])),
      ylim = c(min(xy[, 2]), max(xy[, 2])),
      rgba = c(0L, 0L, 0L, 255L),
      cex = 0,
      output.raster = TRUE
    )

### Arguments

`xy` | 2-column float matrix with point coordinates. As usual with rasters in R, X axis grows right, and Y axis grows DOWN. Flipping `ylim` causes the usual mathematical behavior.
`size` | 2-element vector integer size of the result raster, defaults to `c(512,512)`.
`xlim, ylim` | Float limits as usual (position of the first pixel on the left/top, and the last pixel on the right/bottom). You can easily flip the top/bottom to the "usual" mathematical system by flipping the `ylim` vector.
`rgba` | 4-row matrix with color values of 0-255, or just a single 4-item vector for `c(r,g,b,a)`. Best created with `col2rgb(..., alpha=TRUE)`.
`cex` | Additional point radius in pixels, 0=single-pixel dots (fastest)
`output.raster` | Output R-style raster (as.raster)? Default TRUE. Raw array output can be used much faster, e.g. for use with png::writePNG.

### Value

Raster with the result.

### Examples

    library(scattermore)
    plot(scattermore(cbind(rnorm(1e7),rnorm(1e7)), rgba=c(64,128,192,10)))

[Package scattermore version 0.7 Index]