Points#

class sage.plot.point.Point(xdata, ydata, options)#

Bases: GraphicPrimitive_xydata

Primitive class for the point graphics type. See point?, point2d? or point3d? for information about actually plotting points.

INPUT:

  • xdata – list of x values for points in Point object

  • ydata – list of y values for points in Point object

  • options – dict of valid plot options to pass to constructor

EXAMPLES:

Note this should normally be used indirectly via point() and friends:

sage: from sage.plot.point import Point
sage: P = Point([1,2],[2,3],{'alpha':.5})
sage: P
Point set defined by 2 point(s)
sage: P.options()['alpha']
0.500000000000000
sage: P.xdata
[1, 2]
plot3d(z=0, **kwds)#

Plots a two-dimensional point in 3-D, with default height zero.

INPUT:

  • z - optional 3D height above \(xy\)-plane. May be a list if self is a list of points.

EXAMPLES:

One point:

sage: A = point((1, 1))
sage: a = A[0]; a
Point set defined by 1 point(s)
sage: b = a.plot3d()
../../_images/point-1.svg

One point with a height:

sage: A = point((1, 1))
sage: a = A[0]; a
Point set defined by 1 point(s)
sage: b = a.plot3d(z=3)
sage: b.loc[2]
3.0
../../_images/point-2.svg

Multiple points:

sage: P = point([(0, 0), (1, 1)])
sage: p = P[0]; p
Point set defined by 2 point(s)
sage: q = p.plot3d(size=22)
../../_images/point-3.svg

Multiple points with different heights:

sage: P = point([(0, 0), (1, 1)])
sage: p = P[0]
sage: q = p.plot3d(z=[2,3])
sage: q.all[0].loc[2]
2.0
sage: q.all[1].loc[2]
3.0
../../_images/point-4.svg

Note that keywords passed must be valid point3d options:

sage: A = point((1, 1), size=22)
sage: a = A[0]; a
Point set defined by 1 point(s)
sage: b = a.plot3d()
sage: b.size
22
sage: b = a.plot3d(pointsize=23)  # only 2D valid option
sage: b.size
22
sage: b = a.plot3d(size=23) # correct keyword
sage: b.size
23
sage.plot.point.point(points, **kwds)#

Return either a 2-dimensional or 3-dimensional point or sum of points.

INPUT:

  • points - either a single point (as a tuple), a list of points, a single complex number, or a list of complex numbers.

For information regarding additional arguments, see either point2d? or point3d?.

EXAMPLES:

sage: point((1, 2))
Graphics object consisting of 1 graphics primitive
../../_images/point-5.svg
sage: point((1, 2, 3))
Graphics3d Object
../../_images/point-6.svg
sage: point([(0, 0), (1, 1)])
Graphics object consisting of 1 graphics primitive
../../_images/point-7.svg
sage: point([(0, 0, 1), (1, 1, 1)])
Graphics3d Object
../../_images/point-8.svg

Extra options will get passed on to show(), as long as they are valid:

sage: point([(cos(theta), sin(theta))                                           # needs sage.symbolic
....:        for theta in srange(0, 2*pi, pi/8)], frame=True)
Graphics object consisting of 1 graphics primitive
sage: point([(cos(theta), sin(theta))               # These are equivalent      # needs sage.symbolic
....:        for theta in srange(0, 2*pi, pi/8)]).show(frame=True)
sage.plot.point.point2d(points, alpha=1, aspect_ratio='automatic', faceted=False, legend_color=None, legend_label=None, marker='o', markeredgecolor=None, rgbcolor=(0, 0, 1), size=10, **options)#

A point of size size defined by point = \((x, y)\).

INPUT:

  • points – either a single point (as a tuple), a list of points, a single complex number, or a list of complex numbers

  • alpha – how transparent the point is

  • faceted – if True, color the edge of the point (only for 2D plots)

  • hue – the color given as a hue

  • legend_color – the color of the legend text

  • legend_label – the label for this item in the legend

  • marker – the marker symbol for 2D plots only (see documentation of plot() for details)

  • markeredgecolor – the color of the marker edge (only for 2D plots)

  • rgbcolor – the color as an RGB tuple

  • size – how big the point is (i.e., area in points^2=(1/72 inch)^2)

  • zorder – the layer level in which to draw

EXAMPLES:

A purple point from a single tuple of coordinates:

sage: point((0.5, 0.5), rgbcolor=hue(0.75))
Graphics object consisting of 1 graphics primitive
../../_images/point-9.svg

Points with customized markers and edge colors:

sage: r = [(random(), random()) for _ in range(10)]
sage: point(r, marker='d', markeredgecolor='red', size=20)
Graphics object consisting of 1 graphics primitive
../../_images/point-10.svg

Passing an empty list returns an empty plot:

sage: point([])
Graphics object consisting of 0 graphics primitives
sage: import numpy; point(numpy.array([]))
Graphics object consisting of 0 graphics primitives

If you need a 2D point to live in 3-space later, this is possible:

sage: A = point((1, 1))
sage: a = A[0]; a
Point set defined by 1 point(s)
sage: b = a.plot3d(z=3)
../../_images/point-11.svg

This is also true with multiple points:

sage: P = point([(0, 0), (1, 1)])
sage: p = P[0]
sage: q = p.plot3d(z=[2,3])
../../_images/point-12.svg

Here are some random larger red points, given as a list of tuples:

sage: point(((0.5, 0.5), (1, 2), (0.5, 0.9), (-1, -1)), rgbcolor=hue(1), size=30)
Graphics object consisting of 1 graphics primitive
../../_images/point-13.svg

And an example with a legend:

sage: point((0, 0), rgbcolor='black', pointsize=40, legend_label='origin')
Graphics object consisting of 1 graphics primitive
../../_images/point-14.svg

The legend can be colored:

sage: P = points([(0, 0), (1, 0)], pointsize=40,
....:            legend_label='origin', legend_color='red')
sage: P + plot(x^2, (x, 0, 1), legend_label='plot', legend_color='green')       # needs sage.symbolic
Graphics object consisting of 2 graphics primitives
../../_images/point-15.svg

Extra options will get passed on to show(), as long as they are valid:

sage: point([(cos(theta), sin(theta))                                           # needs sage.symbolic
....:        for theta in srange(0, 2*pi, pi/8)], frame=True)
Graphics object consisting of 1 graphics primitive
sage: point([(cos(theta), sin(theta))               # These are equivalent      # needs sage.symbolic
....:        for theta in srange(0, 2*pi, pi/8)]).show(frame=True)
../../_images/point-16.svg

For plotting data, we can use a logarithmic scale, as long as we are sure not to include any nonpositive points in the logarithmic direction:

sage: point([(1, 2),(2, 4),(3, 4),(4, 8),(4.5, 32)], scale='semilogy', base=2)
Graphics object consisting of 1 graphics primitive
../../_images/point-17.svg

Since Sage Version 4.4 (github issue #8599), the size of a 2d point can be given by the argument size instead of pointsize. The argument pointsize is still supported:

sage: point((3, 4), size=100)
Graphics object consisting of 1 graphics primitive
sage: point((3, 4), pointsize=100)
Graphics object consisting of 1 graphics primitive

We can plot a single complex number:

sage: point(1 + I, pointsize=100)                                               # needs sage.symbolic
Graphics object consisting of 1 graphics primitive
sage: point(sqrt(2) + I, pointsize=100)                                         # needs sage.symbolic
Graphics object consisting of 1 graphics primitive
../../_images/point-18.svg
../../_images/point-19.svg

We can also plot a list of complex numbers:

sage: point([I, 1 + I, 2 + 2*I], pointsize=100)                                 # needs sage.symbolic
Graphics object consisting of 1 graphics primitive
../../_images/point-20.svg
sage.plot.point.points(points, **kwds)#

Return either a 2-dimensional or 3-dimensional point or sum of points.

INPUT:

  • points - either a single point (as a tuple), a list of points, a single complex number, or a list of complex numbers.

For information regarding additional arguments, see either point2d? or point3d?.

EXAMPLES:

sage: point((1, 2))
Graphics object consisting of 1 graphics primitive
../../_images/point-21.svg
sage: point((1, 2, 3))
Graphics3d Object
../../_images/point-22.svg
sage: point([(0, 0), (1, 1)])
Graphics object consisting of 1 graphics primitive
../../_images/point-23.svg
sage: point([(0, 0, 1), (1, 1, 1)])
Graphics3d Object
../../_images/point-24.svg

Extra options will get passed on to show(), as long as they are valid:

sage: point([(cos(theta), sin(theta))                                           # needs sage.symbolic
....:        for theta in srange(0, 2*pi, pi/8)], frame=True)
Graphics object consisting of 1 graphics primitive
sage: point([(cos(theta), sin(theta))               # These are equivalent      # needs sage.symbolic
....:        for theta in srange(0, 2*pi, pi/8)]).show(frame=True)