"""
colorbar - Plot a colorbar.
"""
from pygmt.clib import Session
from pygmt.helpers import build_arg_string, fmt_docstring, kwargs_to_strings, use_alias
@fmt_docstring
@use_alias(
R="region",
J="projection",
B="frame",
C="cmap",
D="position",
F="box",
G="truncate",
I="shading",
W="scale",
V="verbose",
X="xshift",
Y="yshift",
c="panel",
p="perspective",
t="transparency",
)
@kwargs_to_strings(
R="sequence", G="sequence", I="sequence", c="sequence_comma", p="sequence"
)
def colorbar(self, **kwargs):
r"""
Plot a gray or color scale-bar on maps.
Both horizontal and vertical scales are supported. For CPTs with
gradational colors (i.e., the lower and upper boundary of an interval
have different colors) we will interpolate to give a continuous scale.
Variations in intensity due to shading/illumination may be displayed by
setting the ``shading`` parameter. Colors may be spaced according to a
linear scale, all be equal size, or by providing a file with individual
tile widths.
Full option list at :gmt-docs:`colorbar.html`
{aliases}
Parameters
----------
frame : str or list
Set color bar boundary frame, labels, and axes attributes.
{CPT}
position : str
[**g**\|\ **j**\|\ **J**\|\ **n**\|\ **x**]\ *refpoint*\
[**+w**\ *length*\ [/\ *width*]]\ [**+e**\ [**b**\|\ **f**][*length*]]\
[**+h**\|\ **v**][**+j**\ *justify*]\
[**+m**\ [**a**\|\ **c**\|\ **l**\|\ **u**]]\
[**+n**\ [*txt*]][**+o**\ *dx*\ [/*dy*]].
Defines the reference point on the map for the color scale using one of
four coordinate systems: (1) Use **g** for map (user) coordinates, (2)
use **j** or **J** for setting *refpoint* via a 2-char justification
code that refers to the (invisible) map domain rectangle, (3) use **n**
for normalized (0-1) coordinates, or (4) use **x** for plot
coordinates (inches, cm, etc.). All but **x** requires both ``region``
and ``projection`` to be specified. Append **+w** followed by the
length and width of the color bar. If width is not specified then it is
set to 4% of the given length. Give a negative length to reverse
the scale bar. Append **+h** to get a horizontal scale
[Default is vertical (**+v**)]. By default, the anchor point on the
scale is assumed to be the bottom left corner (**BL**), but this can be
changed by appending **+j** followed by a 2-char justification code
*justify*.
box : bool or str
[**+c**\ *clearances*][**+g**\ *fill*][**+i**\ [[*gap*/]\ *pen*]]\
[**+p**\ [*pen*]][**+r**\ [*radius*]][**+s**\ [[*dx*/*dy*/][*shade*]]].
If set to ``True``, draws a rectangular border around the color scale.
Alternatively, specify a different pen with **+p**\ *pen*. Add
**+g**\ *fill* to fill the scale panel [default is no fill]. Append
**+c**\ *clearance* where *clearance* is either gap, xgap/ygap, or
lgap/rgap/bgap/tgap where these items are uniform, separate in x- and
y-direction, or individual side spacings between scale and border.
Append **+i** to draw a secondary, inner border as well. We use a
uniform gap between borders of 2p and the :gmt-term:`MAP_DEFAULTS_PEN`
unless other values are specified. Append **+r** to draw rounded
rectangular borders instead, with a 6p corner radius. You can override
this radius by appending another value. Finally, append **+s** to draw
an offset background shaded region. Here, *dx/dy* indicates the shift
relative to the foreground frame [4p/-4p] and shade sets the fill
style to use for shading [default is gray50].
truncate : list or str
*zlo*/*zhi*.
Truncate the incoming CPT so that the lowest and highest z-levels are
to *zlo* and *zhi*. If one of these equal NaN then we leave that end of
the CPT alone. The truncation takes place before the plotting.
scale : float
Multiply all z-values in the CPT by the provided scale. By default
the CPT is used as is.
shading : str or list or bool
Add illumination effects. Passing a single numerical value sets the
range of intensities from -value to +value. If not specified, 1 is
used. Alternatively, set ``shading=[low, high]`` to specify an
asymmetric intensity range from *low* to *high*. [Default is no
illumination].
{V}
{XY}
{c}
{p}
{t}
"""
kwargs = self._preprocess(**kwargs) # pylint: disable=protected-access
with Session() as lib:
lib.call_module(module="colorbar", args=build_arg_string(kwargs))