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matplotlib.pyplot.plot

matplotlib.pyplot.plot(*args, **kwargs)

Plot y versus x as lines and/or markers.

Call signatures:

plot([x], y, [fmt], data=None, **kwargs)
plot([x], y, [fmt], [x2], y2, [fmt2], ..., **kwargs)

The coordinates of the points or line nodes are given by x, y.

The optional parameter fmt is a convenient way for defining basic formatting like color, marker and linestyle. It’s a shortcut string notation described in the Notes section below.

>>> plot(x, y)        # plot x and y using default line style and color
>>> plot(x, y, 'bo')  # plot x and y using blue circle markers
>>> plot(y)           # plot y using x as index array 0..N-1
>>> plot(y, 'r+')     # ditto, but with red plusses

You can use Line2D properties as keyword arguments for more control on the appearance. Line properties and fmt can be mixed. The following two calls yield identical results:

>>> plot(x, y, 'go--', linewidth=2, markersize=12)
>>> plot(x, y, color='green', marker='o', linestyle='dashed', linewidth=2, markersize=12)

When conflicting with fmt, keyword arguments take precedence.

Plotting labelled data

There’s a convenient way for plotting objects with labelled data (i.e. data that can be accessed by index obj['y']). Instead of giving the data in x and y, you can provide the object in the data parameter and just give the labels for x and y:

>>> plot('xlabel', 'ylabel', data=obj)

All indexable objects are supported. This could e.g. be a dict, a pandas.DataFame or a structured numpy array.

Plotting multiple sets of data

There are various ways to plot multiple sets of data.

  • The most straight forward way is just to call plot multiple times. Example:

    >>> plot(x1, y1, 'bo')
>>> plot(x2, y2, 'go')

  • Alternatively, if your data is already a 2d array, you can pass it directly to x, y. A separate data set will be drawn for every column.

    Example: an array a where the first column represents the x values and the other columns are the y columns:

    >>> plot(a[0], a[1:])

  • The third way is to specify multiple sets of [x], y, [fmt] groups:

    >>> plot(x1, y1, 'g^', x2, y2, 'g-')

    In this case, any additional keyword argument applies to all datasets. Also this syntax cannot be combined with the data parameter.

By default, each line is assigned a different style specified by a ‘style cycle’. The fmt and line property parameters are only necessary if you want explicit deviations from these defaults. Alternatively, you can also change the style cycle using the ‘axes.prop_cycle’ rcParam.

Parameters:

x, y : array-like or scalar

The horizontal / vertical coordinates of the data points. x values are optional. If not given, they default to [0, ..., N-1].

Commonly, these parameters are arrays of length N. However, scalars are supported as well (equivalent to an array with constant value).

The parameters can also be 2-dimensional. Then, the columns represent separate data sets.

fmt : str, optional

A format string, e.g. ‘ro’ for red circles. See the Notes section for a full description of the format strings.

Format strings are just an abbreviation for quickly setting basic line properties. All of these and more can also be controlled by keyword arguments.

data : indexable object, optional

An object with labelled data. If given, provide the label names to plot in x and y.

Note

Technically there’s a slight ambiguity in calls where the second label is a valid fmt. plot('n', 'o', data=obj) could be plt(x, y) or plt(y, fmt). In such cases, the former interpretation is chosen, but a warning is issued. You may suppress the warning by adding an empty format string plot('n', 'o', '', data=obj).
Returns:

lines

A list of Line2D objects that were added.
Other Parameters:
 

scalex, scaley : bool, optional, default: True

These parameters determined if the view limits are adapted to the data limits. The values are passed on to autoscale_view.

**kwargs : Line2D properties, optional

kwargs are used to specify properties like a line label (for auto legends), linewidth, antialiasing, marker face color. Example:

>>> plot([1,2,3], [1,2,3], 'go-', label='line 1', linewidth=2)
>>> plot([1,2,3], [1,4,9], 'rs',  label='line 2')

If you make multiple lines with one plot command, the kwargs apply to all those lines.

Here is a list of available Line2D properties:

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 (0.0 transparent through 1.0 opaque)
animated bool
antialiased or aa bool
clip_box a Bbox instance
clip_on bool
clip_path [(Path, Transform) | Patch | None]
color or c any matplotlib color
contains a callable function
dash_capstyle [‘butt’ | ‘round’ | ‘projecting’]
dash_joinstyle [‘miter’ | ‘round’ | ‘bevel’]
dashes sequence of on/off ink in points
drawstyle [‘default’ | ‘steps’ | ‘steps-pre’ | ‘steps-mid’ | ‘steps-post’]
figure a Figure instance
fillstyle [‘full’ | ‘left’ | ‘right’ | ‘bottom’ | ‘top’ | ‘none’]
gid an id string
label object
linestyle or ls [‘solid’ | ‘dashed’, ‘dashdot’, ‘dotted’ | (offset, on-off-dash-seq) | '-' | '--' | '-.' | ':' | 'None' | ' ' | '']
linewidth or lw float value in points
marker A valid marker style
markeredgecolor or mec any matplotlib color
markeredgewidth or mew float value in points
markerfacecolor or mfc any matplotlib color
markerfacecoloralt or mfcalt any matplotlib color
markersize or ms float
markevery [None | int | length-2 tuple of int | slice | list/array of int | float | length-2 tuple of float]
path_effects AbstractPathEffect
picker float distance in points or callable pick function fn(artist, event)
pickradius float distance in points
rasterized bool or None
sketch_params (scale: float, length: float, randomness: float)
snap bool or None
solid_capstyle [‘butt’ | ‘round’ | ‘projecting’]
solid_joinstyle [‘miter’ | ‘round’ | ‘bevel’]
transform a matplotlib.transforms.Transform instance
url a url string
visible bool
xdata 1D array
ydata 1D array
zorder float

See also

scatter
XY scatter plot with markers of variing size and/or color ( sometimes also called bubble chart).

Notes

Format Strings

A format string consists of a part for color, marker and line:

fmt = '[color][marker][line]'

Each of them is optional. If not provided, the value from the style cycle is used. Exception: If line is given, but no marker, the data will be a line without markers.

Colors

The following color abbreviations are supported:

character color
'b' blue
'g' green
'r' red
'c' cyan
'm' magenta
'y' yellow
'k' black
'w' white

If the color is the only part of the format string, you can additionally use any matplotlib.colors spec, e.g. full names ('green') or hex strings ('#008000').

Markers

character description
'.' point marker
',' pixel marker
'o' circle marker
'v' triangle_down marker
'^' triangle_up marker
'<' triangle_left marker
'>' triangle_right marker
'1' tri_down marker
'2' tri_up marker
'3' tri_left marker
'4' tri_right marker
's' square marker
'p' pentagon marker
'*' star marker
'h' hexagon1 marker
'H' hexagon2 marker
'+' plus marker
'x' x marker
'D' diamond marker
'd' thin_diamond marker
'|' vline marker
'_' hline marker

Line Styles

character description
'-' solid line style
'--' dashed line style
'-.' dash-dot line style
':' dotted line style

Example format strings:

'b'    # blue markers with default shape
'ro'   # red circles
'g-'   # green solid line
'--'   # dashed line with default color
'k^:'  # black triangle_up markers connected by a dotted line

Note

In addition to the above described arguments, this function can take a data keyword argument. If such a data argument is given, the following arguments are replaced by data[<arg>]:

  • All arguments with the following names: ‘x’, ‘y’.
© Copyright 2002 - 2012 John Hunter, Darren Dale, Eric Firing, Michael Droettboom and the Matplotlib development team; 2012 - 2017 The Matplotlib development team. Last updated on Jan 23, 2018. Created using Sphinx 1.6.5.