| colourtools {spatstat} | R Documentation |
These functions convert between different formats for specifying a colour in R, determine whether colours are equivalent, and convert colour to greyscale.
col2hex(x) rgb2hex(v) paletteindex(x) samecolour(x,y) complementarycolour(x) to.grey(x, weights=c(1,1,1))
x,y |
Any valid specification for a colour or sequence of colours
accepted by |
v |
A numeric vector of length 3, giving the RGB values (0 to 255) of a single colour, or a 3-column matrix giving the RGB values of several colours. |
weights |
Numeric vector of length 3 giving relative weights for the red, green, and blue channels respectively. |
col2hex converts colours specified in any format
into their hexadecimal character codes.
rgb2hex converts RGB colour values into their hexadecimal
character codes.
paletteindex checks whether the colour or colours specified
by x are available in the default palette returned by
palette(). If so, it returns the index or indices of
the colours in the palette. If not, it returns NA.
samecolour decides whether two colours x and y
are equivalent.
to.grey converts the colour data in x to greyscale colours.
Alternatively x can be an object of class "colourmap"
and to.grey(x) is the modified colour map.
complementarycolour replaces each colour by its
complementary colour in RGB space (the colour obtained by replacing
RGB values (r, g, b) by (255-r, 255-g, 255-b)).
Alternatively x can be an object of class "colourmap"
and complementarycolour(x) is the modified colour map.
For col2hex, rgb2hex and to.grey,
a character vector containing hexadecimal colour codes.
For paletteindex, an integer vector, possibly containing
NA values.
For samecolour, a logical value or logical vector.
paletteindex("green") returns NA because
the green colour in the default palette is called "green3".
Adrian Baddeley Adrian.Baddeley@uwa.edu.au http://www.maths.uwa.edu.au/~adrian/ and Rolf Turner r.turner@auckland.ac.nz
See also the class of colour map objects:
colourmap,
interp.colourmap,
tweak.colourmap.
samecolour("grey", "gray")
paletteindex("grey")
col2hex("orange")
to.grey("orange")
complementarycolour("orange")