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plotting whit subplots in a loop python [duplicate]

Case:
I receive a dataframe with (say 50) columns.
I extract the necessary columns from that dataframe using a condition.
So we have a list of selected columns of our dataframe now. (Say this variable is sel_cols)
I need a bar chart for each of these columns value_counts().
And I need to arrange all these bar charts in 3 columns, and varying number of rows based on number of columns selected in sel_cols.
So, if say 8 columns were selected, I want the figure to have 3 columns and 3 rows, with last subplot empty or just 8 subplots in 3x3 matrix if that is possible.
I could generate each chart separately using following code:
for col in sel_cols:
df[col].value_counts().plot(kind='bar)
plt.show()
plt.show() inside the loop so that each chart is shown and not just the last one.
I also tried appending these charts to a list this way:
charts = []
for col in sel_cols:
charts.append(df[col].value_counts().plot(kind='bar))
I could convert this list into an numpy array through reshape() but then it will have to be perfectly divisible into that shape. So 8 chart objects will not be reshaped into 3x3 array.
Then I tried creating the subplots first in this way:
row = len(sel_cols)//3
fig, axes = plt.subplots(nrows=row,ncols=3)
This way I would get the subplots, but I get two problems:
I end up with extra subplots in the 3 columns which will go unplotted (8 columns example).
I do not know how to plot under each subplots through a loop.
I tried this:
for row in axes:
for chart, col in zip(row,sel_cols):
chart = data[col].value_counts().plot(kind='bar')
But this only plots the last subplot with the last column. All other subplots stays blank.
How to do this with minimal lines of code, possibly without any need for human verification of the final subplots placements?
You may use this sample dataframe:
pd.DataFrame({'A':['Y','N','N','Y','Y','N','N','Y','N'],
'B':['E','E','E','E','F','F','F','F','E'],
'C':[1,1,0,0,1,1,0,0,1],
'D':['P','Q','R','S','P','Q','R','P','Q'],
'E':['E','E','E','E','F','F','G','G','G'],
'F':[1,1,0,0,1,1,0,0,1],
'G':['N','N','N','N','Y','N','N','Y','N'],
'H':['G','G','G','E','F','F','G','F','E'],
'I':[1,1,0,0,1,1,0,0,1],
'J':['Y','N','N','Y','Y','N','N','Y','N'],
'K':['E','E','E','E','F','F','F','F','E'],
'L':[1,1,0,0,1,1,0,0,1],
})
Selected columns are: sel_cols = ['A','B','D','E','G','H','J','K']
Total 8 columns.
Expected output is bar charts for value_counts() of each of these columns arranged in subplots in a figure with 3 columns. Rows to be decided based on number of columns selected, here 8 so 3 rows.

Given OP's sample data:
df = pd.DataFrame({'A':['Y','N','N','Y','Y','N','N','Y','N'],'B':['E','E','E','E','F','F','F','F','E'],'C':[1,1,0,0,1,1,0,0,1],'D':['P','Q','R','S','P','Q','R','P','Q'],'E':['E','E','E','E','F','F','G','G','G'],'F':[1,1,0,0,1,1,0,0,1],'G':['N','N','N','N','Y','N','N','Y','N'],'H':['G','G','G','E','F','F','G','F','E'],'I':[1,1,0,0,1,1,0,0,1],'J':['Y','N','N','Y','Y','N','N','Y','N'],'K':['E','E','E','E','F','F','F','F','E'],'L':[1,1,0,0,1,1,0,0,1]})
sel_cols = list('ABDEGHJK')
data = df[sel_cols].apply(pd.value_counts)
We can plot the columns of data in several ways (in order of simplicity):
DataFrame.plot with subplots param
seaborn.catplot
Loop through plt.subplots
1. DataFrame.plot with subplots param
Set subplots=True with the desired layout dimensions. Unused subplots will be auto-disabled:
data.plot.bar(subplots=True, layout=(3, 3), figsize=(8, 6),
sharex=False, sharey=True, legend=False)
plt.tight_layout()
2. seaborn.catplot
melt the data into long-form (i.e., 1 variable per column, 1 observation per row) and pass it to seaborn.catplot:
import seaborn as sns
melted = data.melt(var_name='var', value_name='count', ignore_index=False).reset_index()
sns.catplot(data=melted, kind='bar', x='index', y='count',
col='var', col_wrap=3, sharex=False)
3. Loop through plt.subplots
zip the columns and axes to iterate in pairs. Use the ax param to place each column onto its corresponding subplot.
If the grid size is larger than the number of columns (e.g., 3*3 > 8), disable the leftover axes with set_axis_off:
fig, axes = plt.subplots(3, 3, figsize=(8, 8), constrained_layout=True, sharey=True)
# plot each col onto one ax
for col, ax in zip(data.columns, axes.flat):
data[col].plot.bar(ax=ax, rot=0)
ax.set_title(col)
# disable leftover axes
for ax in axes.flat[data.columns.size:]:
ax.set_axis_off()

Alternative to the answer by tdy, I tried to do it without seaborn using Matplotlib and a for loop.
Figured it might be better for some who want specific control over subplots with formatting and other parameters, then this is another way:
fig = plt.figure(1,figsize=(16,12))
for i, col in enumerate(sel_cols,1):
fig.add_subplot(3,4,i,)
data[col].value_counts().plot(kind='bar',ax=plt.gca())
plt.title(col)
plt.tight_layout()
plt.show(1)
plt.subplot activates a subplot, while plt.gca() points to the active subplot.

Plot sub-bar charts on a dataframe groupby

Hi I am having some trouble plotting sub-bar charts after a dataframe groupby
Post groupby, the data is as per the below :
I tried the below to create a bar chart.
df_temp[df_temp.index =='ABC'].unstack().plot.bar(figsize=(10,2))
How can I plot a bar charts where the x-axis is the date and y-axis is the count and each row (ABC and EFG) is its own subplot (vertically stacked)
Example below
thanks for your help !

thanks to #r-beginnners
#remove the multi-level column
df.columns = df.columns.droplevel()
#plot the sub-plots
# if y-axis scale to be the same, use sharey=True
df.T.plot(subplots=True, layout=(2,1), kind='bar', sharey=True)

Multiple boxplot with seaborn, but not within the same frame

In case of pandas boxplot, we could use:
for column in df:
plt.figure()
df.boxplot([column])
What could be done equivalently using seaborn, I want to plot multiple boxplots, but not in the same frame, rather for every column individually in loop

You can pass an Axes object to sns.boxplot:
for column in df:
fig, ax = plt.subplots()
sns.boxplot(df[column], ax=ax)

How to plot multiple dataframes to the same plot axes

I have two dataframes, with unique x and y coordinates, and I want to plot them in the same figure.
I am now plotting two dataframes in same figure as such:
plt.plot(df1['x'],df1['y'])
plt.plot(df2['x'],df2['y'])
plt.show
However, pandas also has plotting functionality.
df.plot()
How could I achieve the same as my first example but use the pandas functionality?

To plot all columns against the index as line plots.
ax = df1.plot()
df2.plot(ax=ax)
A single pandas.DataFrame.plot (not subplots=True) returns a matplotlib.axes.Axes, which you can then pass to the second dataframe.
To plot specific columns as x and y. Specifying x and y is required for scatter plots (kind='scatter').
ax = df1.plot(x='Lat', y='Lon', figsize=(8, 8))
df2.plot(ax=ax, x='Lat', y='Lon')

Values missing: Overlaying points on boxplot subplots from a pandas dataframe

I have two dataframes: df1 with 5000 rows and 12 columns and df2 with a single row and identical 12 columns as df1. I would like to plot each column on a separate subplot as a boxplot with values from df1, and overlay it with scatter plots (just one value per boxplot) from df2.
UPDATE: I tried using a transposed df2 with a numerical index. The following code does not give me any error but only one value on the second boxplot is visible.. I can't see the rest
labels = df1.columns.values
fig, axes = plt.subplots(nrows = 3, ncols = 4,gridspec_kw=dict(hspace=0.4))
targets = zip(labels, axes.flatten())
for i, (col, ax) in enumerate(targets):
print col
pd.DataFrame(df1[col]).boxplot(ax=ax, return_tpe = 'axes')
ax.scatter(df2.index[i], df2['mycol'].values[i])
ax.legend()
plt.show()
Tried attaching the image here but I am slow today...
https://drive.google.com/file/d/0B0Bhe_qx3BgGWkJUdE45UEJqSFk/view?usp=sharing
Using pandas plotting:
Getting boxplot subplots only is easy using
ax = df1.plot(subplots = True)
But I don't know how to specify y for the scatter plot
ax = df2.plot(x = df2.plot.index, y = ???, subplots = True)