I am following the tutorial on matplotlib for creating heatmaps: https://matplotlib.org/stable/gallery/images_contours_and_fields/image_annotated_heatmap.html#a-simple-categorical-heatmap
I run the code with a slight modification, which is changing the following line:
ax.grid(which="minor", color="w", linestyle='-', linewidth=3)
into
ax.grid(which="minor", color="black", linestyle='-', linewidth=1)
I get the following plot:
There is a small distortion in the line separating the second row with the third row. The line is not exactly between the rows of cells.
Zooming in on this distortion we have:
I believe this is due to aliasing? Is there a simple fix for this?
Related
When plotting matrices using matplotlib's imshow function the lines of the axes can overlap the actual plot, see the following minimal example (matshow is just a simple wrapper around imshow):
import numpy as np
import matplotlib.pyplot as plt
fig, ax = plt.subplots(figsize=(3,3))
ax.matshow(np.random.random((50, 50)), interpolation="none", cmap="Blues")
plt.savefig("example.png", dpi=300)
I would expect every entry of the matrix to be represented by a square, but in the top row it is quite obvious that the axis is hiding a bit of the plot resulting in non-square entries. The same is happening for the last column. Since I want the complete matrix to be seen - every entry with the same importance - is there any way this can be fixed?
To me, this is just a visualisation issue. If I run your code and maximise the window, I do not see the overlapping you are talking about:
Otherwise, remove the spines but without hiding the ticks:
ax.spines['top'].set_visible(False)
ax.spines['right'].set_visible(False)
ax.spines['bottom'].set_visible(False)
ax.spines['left'].set_visible(False)
EDIT
Reduce the thickness of the borders:
[x.set_linewidth(0.3) for x in ax.spines.values()]
The following is the exported image:
With 0.2 the exported image looks like this:
As a follow up to this question How to put the legend outside the plot in Matplotlib, I'm trying to put my legend outside my Seaborn plot. My simplified code is:
sns.lineplot(data=df,
x='x',
y='y',
hue='z',
palette=some dictionary)
plt.legend(bbox_to_anchor=(1.05, 1), loc=2, borderaxespad=0.)
plt.tight_layout()
However, the legend takes over the majority of the figure!
How can I instruct seaborn/matplotlib to not shrink the main figure but instead add as much whitespace as necessary?
There is a similar question here, however I fail to adapt the provided solutions to my case.
I want to have a jointplot with kind=hex while removing the marginal plot of the x-axis as it contains no information. In the linked question the suggestion is to use JointGrid directly, however Seaborn then seems to to be unable to draw the hexbin plot.
joint_kws = dict(gridsize=70)
g = sns.jointplot(data=all_data, x="Minute of Hour", y="Frequency", kind="hex", joint_kws=joint_kws)
plt.ylim([49.9, 50.1])
plt.xlim([0, 60])
g.ax_joint.axvline(x=30,ymin=49, ymax=51)
plt.show()
plt.close()
How to remove the margin plot over the x-axis?
Why is the vertical line not drawn?
Also is there a way to exchange the right margin to a plot which more clearly resembles the density?
edit: Here is a sample of the dataset (33kB). Read it with pd.read_pickle("./data.pickle")
I've been fiddling with an analog problem (using a scatterplot instead of the hexbin). In the end, the solution to your first point is awkwardly simple. Just add this line :
g.ax_marg_x.remove()
Regarding your second point, I've no clue as to why no line is plotted. But a workaround seems to be to use vlines instead :
g.ax_joint.vlines(x=30, ymin=49, ymax=51)
Concerning your last point, I'm afraid I haven't understood it. If you mean increasing/reducing the margin between the subplots, you can use the space argument stated in the doc.
I am plotting a relplot with Seaborn, but getting the legend (and an empty axis plot) printed under the main plot.
Here is how it looks like (in 2 photos, as my screen isn't that big):
Here is the code I used:
fig, axes = plt.subplots(1, 1, figsize=(12, 5))
clean_df['tax_class_at_sale'] = clean_df['tax_class_at_sale'].apply(str)
sns.relplot(x="sale_price_millions", y='gross_sqft_thousands', hue="neighborhood", data=clean_df, ax=axes)
fig.suptitle('Sale Price by Neighborhood', position=(.5,1.05), fontsize=20)
fig.tight_layout()
fig.show()
Does someone has an idea how to fix that, so that the legend (maybe much smaller, but it's not a problem) is printed next to the plot, and the empty axis disappears?
Here is my dataset form (in 2 screenshot, to capture all columns. "sale_price_millions" is the target column)
Since you failed to provide a Minimal, Complete, and Verifiable example, no one can give you a final working answer because we can't reproduce your figure. Nevertheless, you can try specifying the location for placing the legend as following and see if it works as you want
sns.relplot(x="sale_price_millions", y='gross_sqft_thousands', hue="neighborhood", data=clean_df, ax=axes)
plt.legend(loc=(1.05, 0.5))
I'm plotting a map with legends using the GeoPandas plotting function. When I plot, my legends appear in the upper right corner of the figure. Here is how it looks like:
I wanted to move the legends to the lower part of the graph. I would normally would have done something like this for a normal matplotlib plot:
fig, ax = plt.subplots(1, figsize=(4.5,10))
lima_bank_num.plot(ax=ax, column='quant_cuts', cmap='Blues', alpha=1, legend=True)
ax.legend(loc='lower left')
However, this modification is not taken into account.
This could be done using the legend_kwds argument:
df.plot(column='values', legend=True, legend_kwds={'loc': 'lower right'});
You can access the legend defined on the ax instance with ax.get_legend(). You can then update the location of the legend using the method set_bbox_to_anchor. This doesn't provide the same ease of use as the loc keyword when creating a legend from scratch, but does give control over placement. So, for your example, something like:
leg = ax.get_legend()
leg.set_bbox_to_anchor((0., 0., 0.2, 0.2))
A bit of documentation of set_bbox_to_anchor, though I don't find it extraordinarily helpful.
If you have a horizontal legend and you're trying to simply reduce the gap between the legend and plot, I recommend the colorbar approach detailed at https://gis.stackexchange.com/a/330175/32531 along with passing the pad legend_kwd argument:
legend_kwds={"orientation": "horizontal", "pad": 0.01}