3.6. Plot Styles

3.6.1. Axis naming

import matplotlib.pyplot as plt


x = [1,2,3]
y = [4,5,6]

plt.xlabel('X axis')
plt.ylabel('Y axis')

plt.plot(x, y)
plt.show()  # doctest: +SKIP

3.6.2. Title

import matplotlib.pyplot as plt


x = [1,2,3]
y = [4,5,6]

plt.title('This is my chart')

plt.plot(x, y)
plt.show()  # doctest: +SKIP

import matplotlib.pyplot as plt


x = [1,2,3]
y = [4,5,6]

plt.title('This is my chart\nSecond line')

plt.plot(x, y)
plt.show()  # doctest: +SKIP

3.6.3. Legend

• Good practice: always have labels

import matplotlib.pyplot as plt


x1 = [1,2,3]
y1 = [4,5,6]

x2 = [1,2,3]
y2 = [10,11,12]

plt.plot(x1, y1, label='first line')
plt.plot(x2, y2, label='second line')

plt.legend()
plt.show()  # doctest: +SKIP

3.6.4. Colors

• first color name letter (not recommended):

  • r - red

  • g - green

  • b - blue

  • c - cyan

  • m - magenta

  • y - yellow

  • k - karmin

  • w - white

• color names (X11/CSS4):

  • red

  • green

  • blue

  • cyan

  • magenta

  • yellow

  • karmin

  • white

  • https://en.wikipedia.org/wiki/X11_color_names#Color_name_chart

• hexadecimal code (RGB or RGBA):

  • #FF0000 - red

  • #00FF00 - green

  • #0000FF - blue

  • #FF000033 - semi-transparent red

• tuple (RGB or RGBA):

  • (0.1, 0.2, 0.5)

  • (0.1, 0.2, 0.5, 0.3)

plt.bar(x1, y1, label='Bars 1', color='blue')
plt.bar(x2, y2, label='Bars 2', color='red')

3.6.5. Line styles

• Other line styles https://matplotlib.org/gallery/lines_bars_and_markers/linestyles.html#sphx-glr-gallery-lines-bars-and-markers-linestyles-py

Figure 3.15. Basic line styles

Figure 3.16. Advanced line styles

pylab.plot(x, y, color="red", linestyle='--')

Table 3.6. fmt parameters

Character	Description
-	solid line style
--	dashed line style
-.	dash-dot line style
:	dotted line style
.	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

3.6.6. Line2D parameters

Table 3.7. Line2D parameters

Property	Value Type
alpha	float
animated	[True | False]
antialiased or aa	[True | False]
clip_box	a matplotlib.transform.Bbox instance
clip_on	[True | False]
clip_path	a Path instance and a Transform instance, a Patch
color or c	any matplotlib color
contains	the hit testing function
dash_capstyle	['butt' | 'round' | 'projecting']
dash_joinstyle	['miter' | 'round' | 'bevel']
dashes	sequence of on/off ink in points
data	(np.array xdata, np.array ydata)
figure	a matplotlib.figure.Figure instance
label	any string
linestyle or ls	[ '-' | '--' | '-.' | ':' | 'steps' | ...]
linewidth or lw	float value in points
lod	[True | False]
marker	[ '+' | ',' | '.' | '1' | '2' | '3' | '4' ]
markeredgecolor or mec	any matplotlib color
markeredgewidth or mew	float value in points
markerfacecolor or mfc	any matplotlib color
markersize or ms	float
markevery	[ None | integer | (startind, stride) ]
picker	used in interactive line selection
pickradius	the line pick selection radius
solid_capstyle	['butt' | 'round' | 'projecting']
solid_joinstyle	['miter' | 'round' | 'bevel']
transform	a matplotlib.transforms.Transform instance
visible	[True | False]
xdata	np.array
ydata	np.array
zorder	any number