Arrows¶

class
sage.plot.arrow.
Arrow
(xtail, ytail, xhead, yhead, options)¶ Bases:
sage.plot.primitive.GraphicPrimitive
Primitive class that initializes the (line) arrow graphics type
EXAMPLES:
We create an arrow graphics object, then take the 0th entry in it to get the actual Arrow graphics primitive:
sage: P = arrow((0,1), (2,3))[0] sage: type(P) <class 'sage.plot.arrow.Arrow'> sage: P Arrow from (0.0,1.0) to (2.0,3.0)

get_minmax_data
()¶ Returns a bounding box for this arrow.
EXAMPLES:
sage: d = arrow((1,1), (5,5)).get_minmax_data() sage: d['xmin'] 1.0 sage: d['xmax'] 5.0

plot3d
(ztail=0, zhead=0, **kwds)¶ Takes 2D plot and places it in 3D.
EXAMPLES:
sage: A = arrow((0,0),(1,1))[0].plot3d() sage: A.jmol_repr(A.testing_render_params())[0] 'draw line_1 diameter 2 arrow {0.0 0.0 0.0} {1.0 1.0 0.0} '
Note that we had to index the arrow to get the Arrow graphics primitive. We can also change the height via the
Graphics.plot3d()
method, but only as a whole:sage: A = arrow((0,0),(1,1)).plot3d(3) sage: A.jmol_repr(A.testing_render_params())[0][0] 'draw line_1 diameter 2 arrow {0.0 0.0 3.0} {1.0 1.0 3.0} '
Optional arguments place both the head and tail outside the \(xy\)plane, but at different heights. This must be done on the graphics primitive obtained by indexing:
sage: A=arrow((0,0),(1,1))[0].plot3d(3,4) sage: A.jmol_repr(A.testing_render_params())[0] 'draw line_1 diameter 2 arrow {0.0 0.0 3.0} {1.0 1.0 4.0} '


class
sage.plot.arrow.
CurveArrow
(path, options)¶ Bases:
sage.plot.primitive.GraphicPrimitive
Returns an arrow graphics primitive along the provided path (bezier curve).
EXAMPLES:
sage: from sage.plot.arrow import CurveArrow sage: b = CurveArrow(path=[[(0,0),(.5,.5),(1,0)],[(.5,1),(0,0)]], ....: options={}) sage: b CurveArrow from (0, 0) to (0, 0)

get_minmax_data
()¶ Returns a dictionary with the bounding box data.
EXAMPLES:
sage: from sage.plot.arrow import CurveArrow sage: b = CurveArrow(path=[[(0,0),(.5,.5),(1,0)],[(.5,1),(0,0)]], ....: options={}) sage: d = b.get_minmax_data() sage: d['xmin'] 0.0 sage: d['xmax'] 1.0


sage.plot.arrow.
arrow
(tailpoint=None, headpoint=None, **kwds)¶ Returns either a 2dimensional or 3dimensional arrow depending on value of points.
For information regarding additional arguments, see either arrow2d? or arrow3d?.
EXAMPLES:
sage: arrow((0,0), (1,1)) Graphics object consisting of 1 graphics primitive
sage: arrow((0,0,1), (1,1,1)) Graphics3d Object

sage.plot.arrow.
arrow2d
(tailpoint=None, headpoint=None, path=None, head=1, linestyle='solid', rgbcolor=(0, 0, 1), width=2, zorder=2, legend_label=None, **options)¶ If
tailpoint
andheadpoint
are provided, returns an arrow from (xtail, ytail) to (xhead, yhead). Iftailpoint
orheadpoint
is None andpath
is not None, returns an arrow along the path. (See further info on paths inbezier_path
).INPUT:
tailpoint
 the starting point of the arrowheadpoint
 where the arrow is pointing topath
 the list of points and control points (see bezier_path for detail) that the arrow will follow from source to destinationhead
 0, 1 or 2, whether to draw the head at the start (0), end (1) or both (2) of the path (using 0 will swap headpoint and tailpoint). This is ignored in 3D plotting.linestyle
 (default:'solid'
) The style of the line, which is one of'dashed'
,'dotted'
,'solid'
,'dashdot'
, or''
,':'
,''
,'.'
, respectively.width
 (default: 2) the width of the arrow shaft, in pointscolor
 (default: (0,0,1)) the color of the arrow (as an RGB tuple or a string)hue
 the color of the arrow (as a number)arrowsize
 the size of the arrowheadarrowshorten
 the length in points to shorten the arrow (ignored if using path parameter)legend_label
 the label for this item in the legendlegend_color
 the color for the legend labelzorder
 the layer level to draw the arrow– note that this is ignored in 3D plotting.
EXAMPLES:
A straight, blue arrow:
sage: arrow2d((1,1), (3,3)) Graphics object consisting of 1 graphics primitive
Make a red arrow:
sage: arrow2d((1,1), (2,3), color=(1,0,0)) Graphics object consisting of 1 graphics primitive
sage: arrow2d((1,1), (2,3), color='red') Graphics object consisting of 1 graphics primitive
You can change the width of an arrow:
sage: arrow2d((1,1), (3,3), width=5, arrowsize=15) Graphics object consisting of 1 graphics primitive
Use a dashed line instead of a solid one for the arrow:
sage: arrow2d((1,1), (3,3), linestyle='dashed') Graphics object consisting of 1 graphics primitive sage: arrow2d((1,1), (3,3), linestyle='') Graphics object consisting of 1 graphics primitive
A pretty circle of arrows:
sage: sum([arrow2d((0,0), (cos(x),sin(x)), hue=x/(2*pi)) for x in [0..2*pi,step=0.1]]) Graphics object consisting of 63 graphics primitives
If we want to draw the arrow between objects, for example, the boundaries of two lines, we can use the
arrowshorten
option to make the arrow shorter by a certain number of points:sage: L1 = line([(0,0), (1,0)], thickness=10) sage: L2 = line([(0,1), (1,1)], thickness=10) sage: A = arrow2d((0.5,0), (0.5,1), arrowshorten=10, rgbcolor=(1,0,0)) sage: L1 + L2 + A Graphics object consisting of 3 graphics primitives
If BOTH
headpoint
andtailpoint
are None, then an empty plot is returned:sage: arrow2d(headpoint=None, tailpoint=None) Graphics object consisting of 0 graphics primitives
We can also draw an arrow with a legend:
sage: arrow((0,0), (0,2), legend_label='up', legend_color='purple') Graphics object consisting of 1 graphics primitive
Extra options will get passed on to
Graphics.show()
, as long as they are valid:sage: arrow2d((2,2), (7,1), frame=True) Graphics object consisting of 1 graphics primitive
sage: arrow2d((2,2), (7,1)).show(frame=True)