matplotlib.axes.Axes.quiver
-
Axes.quiver(*args, data=None, **kw)
[source] -
Plot a 2-D field of arrows.
Call signatures:
quiver(U, V, **kw) quiver(U, V, C, **kw) quiver(X, Y, U, V, **kw) quiver(X, Y, U, V, C, **kw)
U and V are the arrow data, X and Y set the location of the arrows, and C sets the color of the arrows. These arguments may be 1-D or 2-D arrays or sequences.
If X and Y are absent, they will be generated as a uniform grid. If U and V are 2-D arrays and X and Y are 1-D, and if
len(X)
andlen(Y)
match the column and row dimensions of U, then X and Y will be expanded withnumpy.meshgrid()
.The default settings auto-scales the length of the arrows to a reasonable size. To change this behavior see the scale and scale_units kwargs.
The defaults give a slightly swept-back arrow; to make the head a triangle, make headaxislength the same as headlength. To make the arrow more pointed, reduce headwidth or increase headlength and headaxislength. To make the head smaller relative to the shaft, scale down all the head parameters. You will probably do best to leave minshaft alone.
linewidths and edgecolors can be used to customize the arrow outlines.
Parameters: -
X : 1D or 2D array, sequence, optional
-
The x coordinates of the arrow locations
-
Y : 1D or 2D array, sequence, optional
-
The y coordinates of the arrow locations
-
U : 1D or 2D array or masked array, sequence
-
The x components of the arrow vectors
-
V : 1D or 2D array or masked array, sequence
-
The y components of the arrow vectors
-
C : 1D or 2D array, sequence, optional
-
The arrow colors
-
units : [ 'width' | 'height' | 'dots' | 'inches' | 'x' | 'y' | 'xy' ]
-
The arrow dimensions (except for length) are measured in multiples of this unit.
'width' or 'height': the width or height of the axis
'dots' or 'inches': pixels or inches, based on the figure dpi
'x', 'y', or 'xy': respectively X, Y, or
in data units
The arrows scale differently depending on the units. For 'x' or 'y', the arrows get larger as one zooms in; for other units, the arrow size is independent of the zoom state. For 'width or 'height', the arrow size increases with the width and height of the axes, respectively, when the window is resized; for 'dots' or 'inches', resizing does not change the arrows.
-
angles : [ 'uv' | 'xy' ], array, optional
-
Method for determining the angle of the arrows. Default is 'uv'.
'uv': the arrow axis aspect ratio is 1 so that if U*==*V the orientation of the arrow on the plot is 45 degrees counter-clockwise from the horizontal axis (positive to the right).
'xy': arrows point from (x,y) to (x+u, y+v). Use this for plotting a gradient field, for example.
Alternatively, arbitrary angles may be specified as an array of values in degrees, counter-clockwise from the horizontal axis.
Note: inverting a data axis will correspondingly invert the arrows only with
angles='xy'
. -
scale : None, float, optional
-
Number of data units per arrow length unit, e.g., m/s per plot width; a smaller scale parameter makes the arrow longer. Default is None.
If None, a simple autoscaling algorithm is used, based on the average vector length and the number of vectors. The arrow length unit is given by the scale_units parameter
-
scale_units : [ 'width' | 'height' | 'dots' | 'inches' | 'x' | 'y' | 'xy' ], None, optional
-
If the scale kwarg is None, the arrow length unit. Default is None.
e.g. scale_units is 'inches', scale is 2.0, and
(u,v) = (1,0)
, then the vector will be 0.5 inches long.If scale_units is 'width'/'height', then the vector will be half the width/height of the axes.
If scale_units is 'x' then the vector will be 0.5 x-axis units. To plot vectors in the x-y plane, with u and v having the same units as x and y, use
angles='xy', scale_units='xy', scale=1
. -
width : scalar, optional
-
Shaft width in arrow units; default depends on choice of units, above, and number of vectors; a typical starting value is about 0.005 times the width of the plot.
-
headwidth : scalar, optional
-
Head width as multiple of shaft width, default is 3
-
headlength : scalar, optional
-
Head length as multiple of shaft width, default is 5
-
headaxislength : scalar, optional
-
Head length at shaft intersection, default is 4.5
-
minshaft : scalar, optional
-
Length below which arrow scales, in units of head length. Do not set this to less than 1, or small arrows will look terrible! Default is 1
-
minlength : scalar, optional
-
Minimum length as a multiple of shaft width; if an arrow length is less than this, plot a dot (hexagon) of this diameter instead. Default is 1.
-
pivot : [ 'tail' | 'mid' | 'middle' | 'tip' ], optional
-
The part of the arrow that is at the grid point; the arrow rotates about this point, hence the name pivot.
-
color : [ color | color sequence ], optional
-
This is a synonym for the
PolyCollection
facecolor kwarg. If C has been set, color has no effect.
See also
-
quiverkey
- Add a key to a quiver plot
Notes
Additional
PolyCollection
keyword arguments:Property Description agg_filter
a filter function, which takes a (m, n, 3) float array and a dpi value, and returns a (m, n, 3) array alpha
float or None animated
bool antialiased
or antialiasedsBoolean or sequence of booleans array
ndarray capstyle
unknown clim
a length 2 sequence of floats; may be overridden in methods that have vmin
andvmax
kwargs.clip_box
a Bbox
instanceclip_on
bool clip_path
[( Path
,Transform
) |Patch
| None]cmap
a colormap or registered colormap name color
matplotlib color arg or sequence of rgba tuples contains
a callable function edgecolor
or edgecolorsmatplotlib color spec or sequence of specs facecolor
or facecolorsmatplotlib color spec or sequence of specs figure
a Figure
instancegid
an id string hatch
[ '/' | '\' | '|' | '-' | '+' | 'x' | 'o' | 'O' | '.' | '*' ] joinstyle
unknown label
object linestyle
or dashes or linestyles['solid' | 'dashed', 'dashdot', 'dotted' | (offset, on-off-dash-seq) | '-'
|'--'
|'-.'
|':'
|'None'
|' '
|''
]linewidth
or linewidths or lwfloat or sequence of floats norm
Normalize
offset_position
[ 'screen' | 'data' ] offsets
float or sequence of floats path_effects
AbstractPathEffect
picker
[None | bool | float | callable] pickradius
float distance in points rasterized
bool or None sketch_params
(scale: float, length: float, randomness: float) snap
bool or None transform
Transform
url
a url string urls
List[str] or None visible
bool zorder
float -
Examples using matplotlib.axes.Axes.quiver
© 2012–2018 Matplotlib Development Team. All rights reserved.
Licensed under the Matplotlib License Agreement.
https://matplotlib.org/2.2.3/api/_as_gen/matplotlib.axes.Axes.quiver.html