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Scatter plot form dataframe with index on x-axis

I've got pandas DataFrame, df, with index named date and the columns columnA, columnB and columnC

I am trying to scatter plot index on a x-axis and columnA on a y-axis using the DataFrame syntax.

When I try:

df.plot(kind='scatter', x='date', y='columnA') 

I ma getting an error KeyError: 'date' probably because the date is not column

df.plot(kind='scatter', y='columnA') 

I am getting an error:

ValueError: scatter requires and x and y column 

so no default index on x-axis.

df.plot(kind='scatter', x=df.index, y='columnA') 

I am getting error

KeyError: "DatetimeIndex(['1818-01-01', '1818-01-02', '1818-01-03', '1818-01-04',\n                           '1818-01-05', '1818-01-06', '1818-01-07', '1818-01-08',\n                           '1818-01-09', '1818-01-10',\n               ...\n                             '2018-03-22', '2018-03-23', '2018-03-24', '2018-03-25',\n                           '2018-03-26', '2018-03-27', '2018-03-28', '2018-03-29',\n                            '2018-03-30', '2018-03-31'],\n   dtype='datetime64[ns]', name='date', length=73139, freq=None) not in index" 

I can plot it if I use matplotlib.pyplot directly

plt.scatter(df.index, df['columnA']) 

Is there a way to plot index as x-axis using the DataFrame kind syntax?

like image 714
Kocur4d Avatar asked Apr 14 '18 18:04

Kocur4d


2 Answers

This is kind of ugly (I think the matplotlib solution you used in your question is better, FWIW), but you can always create a temporary DataFrame with the index as a column usinng

df.reset_index() 

If the index was nameless, the default name will be 'index'. Assuming this is the case, you could use

df.reset_index().plot(kind='scatter', x='index', y='columnA') 
like image 195
Ami Tavory Avatar answered Sep 18 '22 18:09

Ami Tavory


A more simple solution would be:

df['x1'] = df.index 
df.plot(kind='scatter', x='x1', y='columnA') 

Just create the index variable outside of the plot statement.

like image 31
Clovis Avatar answered Sep 17 '22 18:09

Clovis