PyNGL Home > Functions > Color routines

Ngl.new_color

Adds the given color to the end of the color map of the given workstation.

Prototype

index = Ngl.new_color(wks, red, green, blue)

Arguments

wks

The identifier returned from calling Ngl.open_wks.

red, green, blue

Floating point values between 0.0 and 1.0 inclusive.

Return value

index

An integer representing a color index into the current colormap that contains the new color added.

Description

For the given workstation, this function adds the given color (represented by an RGB triplet) to the end of the color map associated with the given workstation. What's returned is the index value of the location of the new color in the color map.

If the color map you are trying to add the new color to already contains the maximum number of colors (256), then you will get a fatal error message, and the returned value will be invalid.

This function is different than the Ngl.set_color procedure in that you are not required to input a color index value for where to put the new color.

See Also

Ngl.set_color, Ngl.draw_colormap, Ngl.get_named_color_index

Examples

See scatter2.py, or, for a simpler example, run the following Python script:

import Ngl

wks = Ngl.open_wks("x11","example")

#
# Draw the current color map.
#
Ngl.draw_colormap(wks)

#
# Add three shades of blue to the end of the colormap.
#
i1 = Ngl.new_color(wks,0.,0.,0.75)
i2 = Ngl.new_color(wks,0.,0.,0.50)
i3 = Ngl.new_color(wks,0.,0.,0.25)

#
# Draw the new current color map; it should have three extra shades
# of blue at the end.
#
Ngl.draw_colormap(wks)

Ngl.end()