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I have a few Pandas DataFrames sharing the same value scale, but having different columns and indices. When invoking df.plot(), I get separate plot images. what I really want is to have them all in the same plot as subplots, but I'm unfortunately failing to come up with a solution to how and would highly appreciate some help.
You can manually create the subplots with matplotlib, and then plot the dataframes on a specific subplot using the ax keyword. For example for 4 subplots (2x2):
import matplotlib.pyplot as plt
fig, axes = plt.subplots(nrows=2, ncols=2)
df1.plot(ax=axes[0,0])
df2.plot(ax=axes[0,1])
...
Here axes is an array which holds the different subplot axes, and you can access one just by indexing axes.
If you want a shared x-axis, then you can provide sharex=True to plt.subplots.
You can see e.gs. in the documentation demonstrating joris answer. Also from the documentation, you could also set subplots=True and layout=(,) within the pandas plot function:
df.plot(subplots=True, layout=(1,2))
You could also use fig.add_subplot() which takes subplot grid parameters such as 221, 222, 223, 224, etc. as described in the post here. Nice examples of plot on pandas data frame, including subplots, can be seen in this ipython notebook.
You can plot multiple subplots of multiple pandas data frames using matplotlib with a simple trick of making a list of all data frame. Then using the for loop for plotting subplots.
Working code:
import matplotlib.pyplot as plt
import pandas as pd
import numpy as np
# dataframe sample data
df1 = pd.DataFrame(np.random.rand(10,2)*100, columns=['A', 'B'])
df2 = pd.DataFrame(np.random.rand(10,2)*100, columns=['A', 'B'])
df3 = pd.DataFrame(np.random.rand(10,2)*100, columns=['A', 'B'])
df4 = pd.DataFrame(np.random.rand(10,2)*100, columns=['A', 'B'])
df5 = pd.DataFrame(np.random.rand(10,2)*100, columns=['A', 'B'])
df6 = pd.DataFrame(np.random.rand(10,2)*100, columns=['A', 'B'])
#define number of rows and columns for subplots
nrow=3
ncol=2
# make a list of all dataframes
df_list = [df1 ,df2, df3, df4, df5, df6]
fig, axes = plt.subplots(nrow, ncol)
# plot counter
count=0
for r in range(nrow):
for c in range(ncol):
df_list[count].plot(ax=axes[r,c])
count+=1
Using this code you can plot subplots in any configuration. You need to define the number of rows nrow and the number of columns ncol. Also, you need to make list of data frames df_list which you wanted to plot.
You can use the familiar Matplotlib style calling a figure and subplot, but you simply need to specify the current axis using plt.gca(). An example:
plt.figure(1)
plt.subplot(2,2,1)
df.A.plot() #no need to specify for first axis
plt.subplot(2,2,2)
df.B.plot(ax=plt.gca())
plt.subplot(2,2,3)
df.C.plot(ax=plt.gca())
etc...
You can use this:
fig = plt.figure()
ax = fig.add_subplot(221)
plt.plot(x,y)
ax = fig.add_subplot(222)
plt.plot(x,z)
...
plt.show()
You may not need to use Pandas at all. Here's a matplotlib plot of cat frequencies:
x = np.linspace(0, 2*np.pi, 400)
y = np.sin(x**2)
f, axes = plt.subplots(2, 1)
for c, i in enumerate(axes):
axes[c].plot(x, y)
axes[c].set_title('cats')
plt.tight_layout()
Option 1: Create subplots from a dictionary of dataframes with long (tidy) data
Assumptions:
There is a dictionary of multiple dataframes of tidy data that are either:
Created by reading in from files
Created by separating a single dataframe into multiple dataframes
The categories, cat, may be overlapping, but all dataframes don't necessarily contain all values of cat
hue='cat'
This example uses a dict of dataframes, but a list of dataframes would be similar.
If the dataframes are wide, use pandas.DataFrame.melt to convert them to long form.
Because dataframes are being iterated through, there's no guarantee that colors will be mapped the same for each plot
A custom color map needs to be created from the unique 'cat' values for all the dataframes
Since the colors will be the same, place one legend to the side of the plots, instead of a legend in every plot
Tested in python 3.10, pandas 1.4.3, matplotlib 3.5.1, seaborn 0.11.2
Imports and Test Data
import pandas as pd
import numpy as np # used for random data
import matplotlib.pyplot as plt
from matplotlib.patches import Patch # for custom legend - square patches
from matplotlib.lines import Line2D # for custom legend - round markers
import seaborn as sns
import math import ceil # determine correct number of subplot
# synthetic data
df_dict = dict()
for i in range(1, 7):
np.random.seed(i) # for repeatable sample data
data_length = 100
data = {'cat': np.random.choice(['A', 'B', 'C'], size=data_length),
'x': np.random.rand(data_length), 'y': np.random.rand(data_length)}
df_dict[i] = pd.DataFrame(data)
# display(df_dict[1].head())
cat x y
0 B 0.944595 0.606329
1 A 0.586555 0.568851
2 A 0.903402 0.317362
3 B 0.137475 0.988616
4 B 0.139276 0.579745
# display(df_dict[6].tail())
cat x y
95 B 0.881222 0.263168
96 A 0.193668 0.636758
97 A 0.824001 0.638832
98 C 0.323998 0.505060
99 C 0.693124 0.737582
Create color mappings and plot
# create color mapping based on all unique values of cat
unique_cat = {cat for v in df_dict.values() for cat in v.cat.unique()} # get unique cats
colors = sns.color_palette('tab10', n_colors=len(unique_cat)) # get a number of colors
cmap = dict(zip(unique_cat, colors)) # zip values to colors
col_nums = 3 # how many plots per row
row_nums = math.ceil(len(df_dict) / col_nums) # how many rows of plots
# create the figue and axes
fig, axes = plt.subplots(row_nums, col_nums, figsize=(9, 6), sharex=True, sharey=True)
# convert to 1D array for easy iteration
axes = axes.flat
# iterate through dictionary and plot
for ax, (k, v) in zip(axes, df_dict.items()):
sns.scatterplot(data=v, x='x', y='y', hue='cat', palette=cmap, ax=ax)
sns.despine(top=True, right=True)
ax.legend_.remove() # remove the individual plot legends
ax.set_title(f'dataset = {k}', fontsize=11)
fig.tight_layout()
# create legend from cmap
# patches = [Patch(color=v, label=k) for k, v in cmap.items()] # square patches
patches = [Line2D([0], [0], marker='o', color='w', markerfacecolor=v, label=k, markersize=8) for k, v in cmap.items()] # round markers
# place legend outside of plot; change the right bbox value to move the legend up or down
plt.legend(title='cat', handles=patches, bbox_to_anchor=(1.06, 1.2), loc='center left', borderaxespad=0, frameon=False)
plt.show()
Option 2: Create subplots from a single dataframe with multiple separate datasets
The dataframes must be in a long form with the same column names.
This option uses pd.concat to combine multiple dataframes into a single dataframe, and .assign to add a new column.
See Import multiple csv files into pandas and concatenate into one DataFrame for creating a single dataframes from a list of files.
This option is easier because it doesn't require manually mapping colors to 'cat'
Combine DataFrames
# using df_dict, with dataframes as values, from the top
# combine all the dataframes in df_dict to a single dataframe with an identifier column
df = pd.concat((v.assign(dataset=k) for k, v in df_dict.items()), ignore_index=True)
# display(df.head())
cat x y dataset
0 B 0.944595 0.606329 1
1 A 0.586555 0.568851 1
2 A 0.903402 0.317362 1
3 B 0.137475 0.988616 1
4 B 0.139276 0.579745 1
# display(df.tail())
cat x y dataset
595 B 0.881222 0.263168 6
596 A 0.193668 0.636758 6
597 A 0.824001 0.638832 6
598 C 0.323998 0.505060 6
599 C 0.693124 0.737582 6
Plot a FacetGrid with seaborn.relplot
sns.relplot(kind='scatter', data=df, x='x', y='y', hue='cat', col='dataset', col_wrap=3, height=3)
Both options create the same result, however, it's less complicated to combine all the dataframes, and plot a figure-level plot with sns.relplot.
Building on #joris response above, if you have already established a reference to the subplot, you can use the reference as well. For example,
ax1 = plt.subplot2grid((50,100), (0, 0), colspan=20, rowspan=10)
...
df.plot.barh(ax=ax1, stacked=True)
Here is a working pandas subplot example, where modes is the column names of the dataframe.
dpi=200
figure_size=(20, 10)
fig, ax = plt.subplots(len(modes), 1, sharex="all", sharey="all", dpi=dpi)
for i in range(len(modes)):
ax[i] = pivot_df.loc[:, modes[i]].plot.bar(figsize=(figure_size[0], figure_size[1]*len(modes)),
ax=ax[i], title=modes[i], color=my_colors[i])
ax[i].legend()
fig.suptitle(name)
import numpy as np
import pandas as pd
imoprt matplotlib.pyplot as plt
fig, ax = plt.subplots(2,2)
df = pd.DataFrame({'A':np.random.randint(1,100,10),
'B': np.random.randint(100,1000,10),
'C':np.random.randint(100,200,10)})
for ax in ax.flatten():
df.plot(ax =ax)
This question is from this tutorial found here:
I want my plot to look like the one below but with time series data and the zoomed data not being x_lim , y_lim data but from a different source.
So in the plot above i would like the intraday data that is from a different source and the plot below would be daily data for some stock. But because they both have different source i cannot use a limit to zoom. For this i will be using yahoo datareader for daily and yfinance for intraday.
The code:
import pandas as pd
from pandas_datareader import data as web
from matplotlib.patches import ConnectionPatch
df = web.DataReader('goog', 'yahoo')
df.Close = pd.to_numeric(df['Close'], errors='coerce')
fig = plt.figure(figsize=(6, 5))
plt.subplots_adjust(bottom = 0., left = 0, top = 1., right = 1)
sub1 = fig.add_subplot(2,2,1)
sub1 = df.Close.plot()
sub2 = fig.add_subplot(2,1,2) # two rows, two columns, second cell
df.Close.pct_change().plot(ax =sub2)
sub2.plot(theta, y, color = 'orange')
con1 = ConnectionPatch(xyA=(df[1:2].index, df[2:3].Close), coordsA=sub1.transData,
xyB=(df[4:5].index, df[5:6].Close), coordsB=sub2.transData, color = 'green')
fig.add_artist(con1)
I am having trouble with xy coordinates. With the code above i am getting :
TypeError: Cannot cast array data from dtype('O') to dtype('float64')
according to the rule 'safe'
xyA=(df[1:2].index, df[2:3].Close)
What i had done here is that my xvalue is the date df[1:2].index and my y value is the price df[2:3].Close
Is converting the df to an array and then ploting my only option here? If there is any other way to get the ConnectionPatch to work kindly please advise.
df.dtypes
High float64
Low float64
Open float64
Close float64
Volume int64
Adj Close float64
dtype: object
The way matplotlib dates are plotted are by converting dates to floats as a number of days, starting with 0 on 1970-1-1, i.e. the POSIX timestamp zero. It’s different from that timestamp as it’s not the same resolution, i.e. “1” is a day instead of a second.
There’s 3 ways to compute that number,
either use matplotlib.dates.date2num
or use .toordinal() which gives you the right resolution and remove the offset corresponding to 1970-1-1,
or get the POSIX timestamp and divide by the number of seconds in a day:
df['Close'] = pd.to_numeric(df['Close'], errors='coerce')
df['Change'] = df['Close'].pct_change()
con1 = ConnectionPatch(xyA=(df.index[0].toordinal() - pd.Timestamp(0).toordinal(), df['Close'].iloc[0]), coordsA=sub1.transData,
xyB=(df.index[1].toordinal() - pd.Timestamp(0).toordinal(), df['Change'].iloc[1]), coordsB=sub2.transData, color='green')
fig.add_artist(con1)
con2 = ConnectionPatch(xyA=(df.index[-1].timestamp() / 86_400, df['Close'].iloc[-1]), coordsA=sub1.transData,
xyB=(df.index[-1].timestamp() / 86_400, df['Change'].iloc[-1]), coordsB=sub2.transData, color='green')
fig.add_artist(con2)
You also need to make sure that you’re using values that are in range for the targeted axes, in your example you use Close values on sub2 which contains pct_change’d values.
Of course if you want the bottom of the boxes as in your example it’s easier to express the coordinates using the axes transform instead of the data transform:
from matplotlib.dates import date2num
con1 = ConnectionPatch(xyA=(0, 0), coordsA=sub1.transAxes,
xyB=(date2num(df.index[1]), df['Change'].iloc[1]), coordsB=sub2.transData, color='green')
fig.add_artist(con1)
con2 = ConnectionPatch(xyA=(1, 0), coordsA=sub1.transAxes,
xyB=(date2num(df.index[-1]), df['Change'].iloc[-1]), coordsB=sub2.transData, color='green')
fig.add_artist(con2)
To plot your candlesticks, I’d recommend using the mplfinance (previously matplotlib.finance) package:
import mplfinance as mpf
sub3 = fig.add_subplot(2, 2, 2)
mpf.plot(df.iloc[30:70], type='candle', ax=sub3)
Putting all this together in a single script, it could look like this:
import pandas as pd, mplfinance as mpf, matplotlib.pyplot as plt
from pandas_datareader import data as web
from matplotlib.patches import ConnectionPatch
from matplotlib.dates import date2num, ConciseDateFormatter, AutoDateLocator
from matplotlib.ticker import PercentFormatter
# Get / compute data
df = web.DataReader('goog', 'yahoo')
df['Close'] = pd.to_numeric(df['Close'], errors='coerce')
df['Change'] = df['Close'].pct_change()
# Pick zoom range
zoom_start = df.index[30]
zoom_end = df.index[30 + 8 * 5] # 8 weeks ~ 2 months
# Create figures / axes
fig = plt.figure(figsize=(18, 12))
top_left = fig.add_subplot(2, 2, 1)
top_right = fig.add_subplot(2, 2, 2)
bottom = fig.add_subplot(2, 1, 2)
fig.subplots_adjust(hspace=.35)
# Plot all 3 data
df['Close'].plot(ax=bottom, linewidth=1, rot=0, title='Daily closing value', color='purple')
bottom.set_ylim(0)
df.loc[zoom_start:zoom_end, 'Change'].plot(ax=top_left, linewidth=1, rot=0, title='Daily Change, zoomed')
top_left.yaxis.set_major_formatter(PercentFormatter())
# Here instead of df.loc[...] use your intra-day data
mpf.plot(df.loc[zoom_start:zoom_end], type='candle', ax=top_right, xrotation=0, show_nontrading=True)
top_right.set_title('Last day OHLC')
# Put ConciseDateFormatters on all x-axes for fancy date display
for ax in fig.axes:
locator = AutoDateLocator()
ax.xaxis.set_major_locator(locator)
ax.xaxis.set_major_formatter(ConciseDateFormatter(locator))
# Add the connection patches
fig.add_artist(ConnectionPatch(
xyA=(0, 0), coordsA=top_left.transAxes,
xyB=(date2num(zoom_start), df.loc[zoom_start, 'Close']), coordsB=bottom.transData,
color='green'
))
fig.add_artist(ConnectionPatch(
xyA=(1, 0), coordsA=top_left.transAxes,
xyB=(date2num(zoom_end), df.loc[zoom_end, 'Close']), coordsB=bottom.transData,
color='green'
))
plt.show()
Say I have a dataframe structured like so:
Name x y
Joe 0,1,5 0,3,8
Sue 0,2,8 1,9,5
...
Harold 0,5,6 0,7,2
I'd like to plot the values in the x and y axis on a line plot based on row. In reality, there are many x and y values, but there is always one x value for every y value in these columns. The name of the plot would be the value in "name".
I've tried to do this by first converting x and y to lists in their own separate columns like so:
df['xval'] = df.['x'].str.split(',')
df['yval'] = df.['y'].str.split(',')
And then passing them to seaborn:
ax = sns.lineplot(x=df['xval'], y=df['yval'], data=df)
However, this does not work because 1) I recieve an error, which I presume is due to attempting to pass a list from a dataframe, claiming:
TypeError: unhashable type: 'list'
And 2) I cannot specify the value for df['name'] for the specific line plot. What's the best way to go about solving this problem?
Data and imports:
import pandas as pd
import seaborn as sns
from matplotlib import pyplot as plt
df = pd.DataFrame({
'name': ['joe', 'sue', 'mike'],
'x': ['0,1,5', '0,2,8', '0,4'],
'y': ['0,3,8', '1,9,5', '1,6']
})
We should convert df into a useable format for plotting. This makes all plotting eaiser. We can take advantage of the fact that x and y have a 1-to-1 relationship. Notice I've added a third name with a 2 xy value as opposed to 3 to show this method will work for varied amounts of x and y per name as long as each row has equal numbers of x and y values.
Creating the plot_df:
# Grab Name Column to Start Plot DF with
plot_df = df.loc[:, ['name']]
# Split X column
plot_df['x'] = df['x'].str.split(',')
# Explode X into Rows
plot_df = plot_df.explode('x').reset_index(drop=True)
# Split and Series Explode y in one step
# This works IF AND ONLY IF a 1-to-1 relationship for x and y
plot_df['y'] = df['y'].str.split(',').explode().reset_index(drop=True)
# These need to be numeric to plot correctly
plot_df.loc[:, ['x', 'y']] = plot_df.loc[:, ['x', 'y']].astype(int)
plot_df:
name x y
0 joe 0 0
1 joe 1 3
2 joe 5 8
3 sue 0 1
4 sue 2 9
5 sue 8 5
6 mike 0 1
7 mike 4 6
References to the methods used in creating plot_df:
DataFrame.loc to subset the dataframe
Series.str.split to split the comma separated values into a list
DataFrame.explode to upscale the DataFrame based on the iterable in x
DataFrame.reset_index to make index unique again after exploding
Series.explode to upscale the lists in the Series y.
Series.reset_index to make index unique again after exploding
DataFrame.astype since the values are initially strings just splitting and exploding is not enough. Will need to convert to a numeric type for them to plot correctly
Plotting (Option 1)
# Plot with hue set to name.
sns.lineplot(data=plot_df, x='x', y='y', hue='name')
plt.show()
References for plotting separate lines:
sns.lineplot to plot. Note the hue argument to create separate lines based on name.
pyplot.show to display.
Plotting (Option 2.a) Subplots:
sns.relplot(data=plot_df, x='x', y='y', col='name', kind='line')
plt.tight_layout()
plt.show()
Plotting (Option 2.b) Subplots:
# Use Grouper From plot_df
grouper = plot_df.groupby('name')
# Create Subplots based on the number of groups (ngroups)
fig, axes = plt.subplots(nrows=grouper.ngroups)
# Iterate over axes and groups
for ax, (grp_name, grp) in zip(axes, grouper):
# Plot from each grp DataFrame on ax from axes
sns.lineplot(data=grp, x='x', y='y', ax=ax, label=grp_name)
plt.show()
References for plotting subplots:
2.a
relplot the row or col parameter can be used to create subplots in a similar way to how hue creates multiple lines. This will return a seaborn.FacetGrid so post processing will be different than lineplot which returns matplotlib.axes.Axes
2.b
groupby to create iterable that can be used to plot subplots.
pyplot.subplots to create subplots to plot on.
groupby.ngroup to count number of groups.
zip to iterate over axes and groups simultaneously.
sns.lineplot to plot. Note label is needed to have legends. grp_name contains the current key that is common in the current grp DataFrame.
pyplot.show to display.
Plotting option 3 (separate plots):
# Plot from each grp DataFrame in it's own plot
for grp_name, grp in plot_df.groupby('name'):
fig, ax = plt.subplots()
sns.lineplot(data=grp, x='x', y='y', ax=ax)
ax.set_title(grp_name)
fig.show()
joe plot
mike plot
sue plot
References for plotting separate plots:
groupby to create iterable that can be used to plot each name separately.
pyplot.subplots to create separate plot to plot on.
sns.lineplot to plot. Note label is needed to have legends. grp_name contains the current key that is common in the current grp DataFrame.
pyplot.show to display.
From what I understood this is what you want.
df = pd.DataFrame()
df['name'] = ['joe', 'sue']
df['x'] = ['0,1,5', '0,2,8']
df['y'] = ['0,3,8', '1,9,5']
df['newx'] = df['x'].str.split(',')
df['newy'] = df['y'].str.split(',')
for i in range(len(df)):
sns.lineplot(x=df.loc[i, 'newx'], y=df.loc[i, 'newy'])
plt.legend(df['name'])
I have a time series data on which I would like to build a overlayed scatterplot and boxplot. The data is as so:
TokenUsed date
0 8 2020-01-05
1 8 2020-01-05
2 8 2020-01-05
3 8 2020-01-05
4 8 2020-01-05
... ... ...
51040 7 2020-02-23
51041 7 2020-02-23
51042 7 2020-02-23
51043 7 2020-02-23
51044 7 2020-02-23
This time series can be neatly shown as a boxplot (I've had trouble with the x-axis being a date, but solved it converting it to string). Now I would like to show only the data on which sum is superior to a threshold (>81) in my case. The code and the resulting image are below:
fig, ax = plt.subplots(figsize = (12,6))
ax = sns.boxplot(x="date", y="TokenUsed", data=df, ax= ax, whis=[0,100])
ax.axhline(81)
plt.locator_params(axis='x', nbins=10)
plt.show()
When I add a scatter plot, I get image (2) and by filtering only those >81 I get image(3). What I don't understand is why it can't seem to match the x-axis between the two graphs!
Code:
fig, ax = plt.subplots(figsize = (12,6))
ax = sns.boxplot(x="date", y="TokenUsed", data=df, ax= ax, whis=[0,100])
# Without filter
ax = sns.scatterplot(x="date", y="TokenUsed", data=df, ax= ax,color=".25")
# Filter
ax = sns.scatterplot(x="date", y="TokenUsed", data=df[df["TokenUsed"]>81], ax= ax,color=".25")
ax.axhline(81)
plt.locator_params(axis='x', nbins=10)
plt.show()
Answer:
Try editing your filtering such that no rows of df are actually removed. That is, apply a mask specifically on the TokenUsed column, such that values are replaced with NaN (rather than the whole row being removed). Here's how I would implement this:
#make a new copy df, use that to plot
df2['TokenUsed'] = df2['TokenUsed'].mask(df2['TokenUsed'] < 81)
ax = sns.scatterplot(x="date", y="TokenUsed", data=df2, ax= ax,color=".25")
Explanation
Caveat: this is really my understanding of what is going on from my own observations; I am not actually aware of the implementation behind the scenes
seaborn is less aware of the dates then you are expecting. When creating the boxplot and using the date column for the x-axis, seaborn groups the data by each unique value in the date column. It orders these strings and then creates an integer position for each of them (starting from 0). The y-data are then plotted against these integer values, and the x-tick-labels are replaced with the corresponding string value. So in your case, there are 8 unique date strings, and they are plotted at x-positions from 0 to 7. Also, it doesn't actually matter that they look like dates. You could add more string values to the date column; their position relative to prior data would depend on their alphabetical order (e.g. I would guess the string '00-00-0000' would appear first and the string '999' would appear last).
The filter df[df["TokenUsed"]>81] removes any rows where the TokenUsed value is below 81. This means that the filtered DataFrame will not have as many string date values as the original data. This then creates the unexpected result when plotting. In your filtered data, the first date with values above 81 is 2020-02-09. So in the scatterplot call, those values get plotted at x=0, which is confusing because the values from 2020-01-05 were plotted at x=0 in the call to boxplot.
The fix is to make sure all the original dates are still present in the filtered data, but to replace the filtered out values with NaN so nothing gets plotted.
Here is the example I used to test this:
import pandas as pd
import numpy as np
import seaborn as sns
import matplotlib.pyplot as plt
# fake data, only one date has values over 80
dr = ['01-05-2020'] * 100 + ['01-12-2020'] * 100 + ['01-19-2020'] * 100
data = list(np.random.randint(0,80,200)) + list(np.random.randint(50,150,100))
df = pd.DataFrame({'date':dr, 'TokenUsed':data})
fig, ax = plt.subplots(figsize = (12,6))
ax = sns.boxplot(x="date", y="TokenUsed", data=df, ax=ax, whis=[0,100])
df2 = df.copy()
df2['TokenUsed'] = df2['TokenUsed'].mask(df2['TokenUsed'] < 81)
# the fix
df2 = df.copy()
df2['TokenUsed'] = df2['TokenUsed'].mask(df2['TokenUsed'] < 81)
ax = sns.scatterplot(x="date", y="TokenUsed", data=df2, ax= ax,color=".25")
ax.axhline(81)
plt.locator_params(axis='x', nbins=10)
plt.show()
If I use the same filter that you applied, I get the same issue.
I have a few Pandas DataFrames sharing the same value scale, but having different columns and indices. When invoking df.plot(), I get separate plot images. what I really want is to have them all in the same plot as subplots, but I'm unfortunately failing to come up with a solution to how and would highly appreciate some help.
You can manually create the subplots with matplotlib, and then plot the dataframes on a specific subplot using the ax keyword. For example for 4 subplots (2x2):
import matplotlib.pyplot as plt
fig, axes = plt.subplots(nrows=2, ncols=2)
df1.plot(ax=axes[0,0])
df2.plot(ax=axes[0,1])
...
Here axes is an array which holds the different subplot axes, and you can access one just by indexing axes.
If you want a shared x-axis, then you can provide sharex=True to plt.subplots.
You can see e.gs. in the documentation demonstrating joris answer. Also from the documentation, you could also set subplots=True and layout=(,) within the pandas plot function:
df.plot(subplots=True, layout=(1,2))
You could also use fig.add_subplot() which takes subplot grid parameters such as 221, 222, 223, 224, etc. as described in the post here. Nice examples of plot on pandas data frame, including subplots, can be seen in this ipython notebook.
You can plot multiple subplots of multiple pandas data frames using matplotlib with a simple trick of making a list of all data frame. Then using the for loop for plotting subplots.
Working code:
import matplotlib.pyplot as plt
import pandas as pd
import numpy as np
# dataframe sample data
df1 = pd.DataFrame(np.random.rand(10,2)*100, columns=['A', 'B'])
df2 = pd.DataFrame(np.random.rand(10,2)*100, columns=['A', 'B'])
df3 = pd.DataFrame(np.random.rand(10,2)*100, columns=['A', 'B'])
df4 = pd.DataFrame(np.random.rand(10,2)*100, columns=['A', 'B'])
df5 = pd.DataFrame(np.random.rand(10,2)*100, columns=['A', 'B'])
df6 = pd.DataFrame(np.random.rand(10,2)*100, columns=['A', 'B'])
#define number of rows and columns for subplots
nrow=3
ncol=2
# make a list of all dataframes
df_list = [df1 ,df2, df3, df4, df5, df6]
fig, axes = plt.subplots(nrow, ncol)
# plot counter
count=0
for r in range(nrow):
for c in range(ncol):
df_list[count].plot(ax=axes[r,c])
count+=1
Using this code you can plot subplots in any configuration. You need to define the number of rows nrow and the number of columns ncol. Also, you need to make list of data frames df_list which you wanted to plot.
You can use the familiar Matplotlib style calling a figure and subplot, but you simply need to specify the current axis using plt.gca(). An example:
plt.figure(1)
plt.subplot(2,2,1)
df.A.plot() #no need to specify for first axis
plt.subplot(2,2,2)
df.B.plot(ax=plt.gca())
plt.subplot(2,2,3)
df.C.plot(ax=plt.gca())
etc...
You can use this:
fig = plt.figure()
ax = fig.add_subplot(221)
plt.plot(x,y)
ax = fig.add_subplot(222)
plt.plot(x,z)
...
plt.show()
You may not need to use Pandas at all. Here's a matplotlib plot of cat frequencies:
x = np.linspace(0, 2*np.pi, 400)
y = np.sin(x**2)
f, axes = plt.subplots(2, 1)
for c, i in enumerate(axes):
axes[c].plot(x, y)
axes[c].set_title('cats')
plt.tight_layout()
Option 1: Create subplots from a dictionary of dataframes with long (tidy) data
Assumptions:
There is a dictionary of multiple dataframes of tidy data that are either:
Created by reading in from files
Created by separating a single dataframe into multiple dataframes
The categories, cat, may be overlapping, but all dataframes don't necessarily contain all values of cat
hue='cat'
This example uses a dict of dataframes, but a list of dataframes would be similar.
If the dataframes are wide, use pandas.DataFrame.melt to convert them to long form.
Because dataframes are being iterated through, there's no guarantee that colors will be mapped the same for each plot
A custom color map needs to be created from the unique 'cat' values for all the dataframes
Since the colors will be the same, place one legend to the side of the plots, instead of a legend in every plot
Tested in python 3.10, pandas 1.4.3, matplotlib 3.5.1, seaborn 0.11.2
Imports and Test Data
import pandas as pd
import numpy as np # used for random data
import matplotlib.pyplot as plt
from matplotlib.patches import Patch # for custom legend - square patches
from matplotlib.lines import Line2D # for custom legend - round markers
import seaborn as sns
import math import ceil # determine correct number of subplot
# synthetic data
df_dict = dict()
for i in range(1, 7):
np.random.seed(i) # for repeatable sample data
data_length = 100
data = {'cat': np.random.choice(['A', 'B', 'C'], size=data_length),
'x': np.random.rand(data_length), 'y': np.random.rand(data_length)}
df_dict[i] = pd.DataFrame(data)
# display(df_dict[1].head())
cat x y
0 B 0.944595 0.606329
1 A 0.586555 0.568851
2 A 0.903402 0.317362
3 B 0.137475 0.988616
4 B 0.139276 0.579745
# display(df_dict[6].tail())
cat x y
95 B 0.881222 0.263168
96 A 0.193668 0.636758
97 A 0.824001 0.638832
98 C 0.323998 0.505060
99 C 0.693124 0.737582
Create color mappings and plot
# create color mapping based on all unique values of cat
unique_cat = {cat for v in df_dict.values() for cat in v.cat.unique()} # get unique cats
colors = sns.color_palette('tab10', n_colors=len(unique_cat)) # get a number of colors
cmap = dict(zip(unique_cat, colors)) # zip values to colors
col_nums = 3 # how many plots per row
row_nums = math.ceil(len(df_dict) / col_nums) # how many rows of plots
# create the figue and axes
fig, axes = plt.subplots(row_nums, col_nums, figsize=(9, 6), sharex=True, sharey=True)
# convert to 1D array for easy iteration
axes = axes.flat
# iterate through dictionary and plot
for ax, (k, v) in zip(axes, df_dict.items()):
sns.scatterplot(data=v, x='x', y='y', hue='cat', palette=cmap, ax=ax)
sns.despine(top=True, right=True)
ax.legend_.remove() # remove the individual plot legends
ax.set_title(f'dataset = {k}', fontsize=11)
fig.tight_layout()
# create legend from cmap
# patches = [Patch(color=v, label=k) for k, v in cmap.items()] # square patches
patches = [Line2D([0], [0], marker='o', color='w', markerfacecolor=v, label=k, markersize=8) for k, v in cmap.items()] # round markers
# place legend outside of plot; change the right bbox value to move the legend up or down
plt.legend(title='cat', handles=patches, bbox_to_anchor=(1.06, 1.2), loc='center left', borderaxespad=0, frameon=False)
plt.show()
Option 2: Create subplots from a single dataframe with multiple separate datasets
The dataframes must be in a long form with the same column names.
This option uses pd.concat to combine multiple dataframes into a single dataframe, and .assign to add a new column.
See Import multiple csv files into pandas and concatenate into one DataFrame for creating a single dataframes from a list of files.
This option is easier because it doesn't require manually mapping colors to 'cat'
Combine DataFrames
# using df_dict, with dataframes as values, from the top
# combine all the dataframes in df_dict to a single dataframe with an identifier column
df = pd.concat((v.assign(dataset=k) for k, v in df_dict.items()), ignore_index=True)
# display(df.head())
cat x y dataset
0 B 0.944595 0.606329 1
1 A 0.586555 0.568851 1
2 A 0.903402 0.317362 1
3 B 0.137475 0.988616 1
4 B 0.139276 0.579745 1
# display(df.tail())
cat x y dataset
595 B 0.881222 0.263168 6
596 A 0.193668 0.636758 6
597 A 0.824001 0.638832 6
598 C 0.323998 0.505060 6
599 C 0.693124 0.737582 6
Plot a FacetGrid with seaborn.relplot
sns.relplot(kind='scatter', data=df, x='x', y='y', hue='cat', col='dataset', col_wrap=3, height=3)
Both options create the same result, however, it's less complicated to combine all the dataframes, and plot a figure-level plot with sns.relplot.
Building on #joris response above, if you have already established a reference to the subplot, you can use the reference as well. For example,
ax1 = plt.subplot2grid((50,100), (0, 0), colspan=20, rowspan=10)
...
df.plot.barh(ax=ax1, stacked=True)
Here is a working pandas subplot example, where modes is the column names of the dataframe.
dpi=200
figure_size=(20, 10)
fig, ax = plt.subplots(len(modes), 1, sharex="all", sharey="all", dpi=dpi)
for i in range(len(modes)):
ax[i] = pivot_df.loc[:, modes[i]].plot.bar(figsize=(figure_size[0], figure_size[1]*len(modes)),
ax=ax[i], title=modes[i], color=my_colors[i])
ax[i].legend()
fig.suptitle(name)
import numpy as np
import pandas as pd
imoprt matplotlib.pyplot as plt
fig, ax = plt.subplots(2,2)
df = pd.DataFrame({'A':np.random.randint(1,100,10),
'B': np.random.randint(100,1000,10),
'C':np.random.randint(100,200,10)})
for ax in ax.flatten():
df.plot(ax =ax)