Making a solid legend

Community matplotlib-users
1

Hello,

I try to make the legend non-translucent, having a solid color and laying above the plot itself.

That's what I try:

import matplotlib.pyplot as plt

fig, ax1 = plt.subplots()
ax1.plot([0, 1], [0, 2], label = "Plot 1")

leg = ax1.legend(loc = 1)
leg.get_frame().set_facecolor("r")
leg.set_alpha(0)

plt.grid()
plt.show()

(you may have to pan the plot)

Taken from:
http://matplotlib.org/examples/api/legend_demo.html
http://matplotlib.org/1.3.0/examples/pylab_examples/legend_translucent.html

The set_alpha seems to have no effect at all. facecolor works, but it is always translucent.

Thanks,
Florian

2

Hello Florian,

A `get_frame()` call seems to be missing in your example. Try with

leg.get_frame().set_facecolor('r')

Note that you can also directly set this when calling `legend`:

import matplotlib.pyplot as plt

fig, ax = plt.subplots()
ax.plot([0, 1], label='Plot 1')

leg = ax.legend(loc='upper left', framealpha=1.0, facecolor='red')

ax.grid()
plt.show()

If you want to fix this for every plot you do, you may want to tweak your
matplotlibrc file or at least the related rcParams in your scrpit, which are
'legend.framecolor' and 'legend.framealpha'.

Best regards,
Adrien

···

On 23/03/2017 14:24, Florian Lindner wrote:

Hello,

I try to make the legend non-translucent, having a solid color and laying above the plot itself.

That's what I try:

import matplotlib.pyplot as plt

fig, ax1 = plt.subplots()
ax1.plot([0, 1], [0, 2], label = "Plot 1")

leg = ax1.legend(loc = 1)
leg.get_frame().set_facecolor("r")
leg.set_alpha(0)

plt.grid()
plt.show()

(you may have to pan the plot)

Taken from:
http://matplotlib.org/examples/api/legend_demo.html
pylab_examples example code: legend_translucent.py — Matplotlib 1.3.0 documentation

The set_alpha seems to have no effect at all. facecolor works, but it is always translucent.

Thanks,
Florian

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Matplotlib-users mailing list
Matplotlib-users at python.org
Matplotlib-users Info Page

3

Hello,

Hello Florian,

A `get_frame()` call seems to be missing in your example. Try with

leg.get_frame().set_facecolor('r')

Note that you can also directly set this when calling `legend`:

import matplotlib.pyplot as plt

fig, ax = plt.subplots()
ax.plot([0, 1], label='Plot 1')

leg = ax.legend(loc='upper left', framealpha=1.0, facecolor='red')

ax.grid()
plt.show()

If you want to fix this for every plot you do, you may want to tweak your
matplotlibrc file or at least the related rcParams in your scrpit, which are
'legend.framecolor' and 'legend.framealpha'.

Oh, cool, that is what I was looking for too.

I found out that my original issue is also related to twinx:

import matplotlib.pyplot as plt

fig, ax1 = plt.subplots()
ax1.plot([0, 1], [0, 2], label = "Plot 1 with some more text")
ax1.legend(framealpha = 1, bbox_to_anchor = (0.1, 1))

ax2 = ax1.twinx()
ax2.plot([0, 1], [2.2, 0], "--", label = "Plot 2 with some more text")
ax2.legend(framealpha = 1, bbox_to_anchor = (1.1,1))

plt.grid()
plt.show()

The second legend is over the right y-axis, the first legend is not over the left y-axis.

Can I set legends in a way they are always above any element?

Thanks,
Florian

···

Am 23.03.2017 um 14:38 schrieb vincent.adrien at gmail.com:

Best regards,
Adrien

On 23/03/2017 14:24, Florian Lindner wrote:

Hello,

I try to make the legend non-translucent, having a solid color and laying above the plot itself.

That's what I try:

import matplotlib.pyplot as plt

fig, ax1 = plt.subplots()
ax1.plot([0, 1], [0, 2], label = "Plot 1")

leg = ax1.legend(loc = 1)
leg.get_frame().set_facecolor("r")
leg.set_alpha(0)

plt.grid()
plt.show()

(you may have to pan the plot)

Taken from:
http://matplotlib.org/examples/api/legend_demo.html
pylab_examples example code: legend_translucent.py — Matplotlib 1.3.0 documentation

The set_alpha seems to have no effect at all. facecolor works, but it is always translucent.

Thanks,
Florian

_______________________________________________
Matplotlib-users mailing list
Matplotlib-users at python.org
Matplotlib-users Info Page

4

I am not an expert of the legend codebase but it seems like you can achieve this
with the following snippet heavily insprired from this [SO
thread](python - Matplotlib: how to adjust zorder of second legend? - Stack Overflow)
and the Matplotlib [tutorial on
legend](http://matplotlib.org/users/legend_guide.html). In a nutshell, you build
a legend-like artist similar to the one of the first axes and display it into
the second axis.

import matplotlib.pyplot as plt

plt.rcParams['legend.framealpha'] = 1.0
plt.rcParams['legend.facecolor'] = '0.95'

fig, ax1 = plt.subplots()
ax1.plot([0, 1], [0, 2], label="Plot 1")

ax2 = ax1.twinx()
ax2.plot([0, 1], [2.2, 0], "--", label="Plot 2")
ax2.legend(bbox_to_anchor=(1, 1))

# Manually add *leg1*, the legend of *ax1*, to *ax2* so it displays "on top"
handles1, labels1 = ax1.get_legend_handles_labels()
leg1 = plt.legend(handles1, labels1, loc="upper left", bbox_to_anchor=(0, 1))
ax2.add_artist(leg1)
# `loc="upper left"` (or anything but "best") is highly recommended, as it
# determines which part of the bbox is anchored to the desired coordinates.
# "best" (the new default btw.) could lead to weird behaviors when changing
# just a bit the anchor position...

# Just in case: here is a simple way to display a single common legend.
# Note the it will replace the previous legend on *ax2*.
#handles1, labels1 = ax1.get_legend_handles_labels()
#handles2, labels2 = ax2.get_legend_handles_labels()
#ax2.legend(handles1+handles2, labels1+labels2, loc="lower center")

plt.grid()
plt.show()

Best,
Adrien

PS: I made a mistake in my previous email. The correct rcParams key are
'legend.framealpha' and *'legend.facecolor'* (not 'legend.framecolor').

···

On 23/03/2017 15:10, Florian Lindner wrote:

Hello,

Am 23.03.2017 um 14:38 schrieb vincent.adrien at gmail.com:

Hello Florian,

A `get_frame()` call seems to be missing in your example. Try with

leg.get_frame().set_facecolor('r')

Note that you can also directly set this when calling `legend`:

import matplotlib.pyplot as plt

fig, ax = plt.subplots()
ax.plot([0, 1], label='Plot 1')

leg = ax.legend(loc='upper left', framealpha=1.0, facecolor='red')

ax.grid()
plt.show()

If you want to fix this for every plot you do, you may want to tweak your
matplotlibrc file or at least the related rcParams in your scrpit, which are
'legend.framecolor' and 'legend.framealpha'.

Oh, cool, that is what I was looking for too.

I found out that my original issue is also related to twinx:

import matplotlib.pyplot as plt

fig, ax1 = plt.subplots()
ax1.plot([0, 1], [0, 2], label = "Plot 1 with some more text")
ax1.legend(framealpha = 1, bbox_to_anchor = (0.1, 1))

ax2 = ax1.twinx()
ax2.plot([0, 1], [2.2, 0], "--", label = "Plot 2 with some more text")
ax2.legend(framealpha = 1, bbox_to_anchor = (1.1,1))

plt.grid()
plt.show()

The second legend is over the right y-axis, the first legend is not over the left y-axis.

Can I set legends in a way they are always above any element?

Thanks,
Florian

Best regards,
Adrien

On 23/03/2017 14:24, Florian Lindner wrote:

Hello,

I try to make the legend non-translucent, having a solid color and laying above the plot itself.

That's what I try:

import matplotlib.pyplot as plt

fig, ax1 = plt.subplots()
ax1.plot([0, 1], [0, 2], label = "Plot 1")

leg = ax1.legend(loc = 1)
leg.get_frame().set_facecolor("r")
leg.set_alpha(0)

plt.grid()
plt.show()

(you may have to pan the plot)

Taken from:
http://matplotlib.org/examples/api/legend_demo.html
pylab_examples example code: legend_translucent.py — Matplotlib 1.3.0 documentation

The set_alpha seems to have no effect at all. facecolor works, but it is always translucent.

Thanks,
Florian

_______________________________________________
Matplotlib-users mailing list
Matplotlib-users at python.org
Matplotlib-users Info Page

_______________________________________________
Matplotlib-users mailing list
Matplotlib-users at python.org
Matplotlib-users Info Page