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Questions tagged [series]

A Series object represents a data series. This may be represented as the SeriesCollection class (Java, C#) or Series class in Python Pandas.

  • A series is not necessarily plotted on a chart; it can store data point values that are used to perform a calculation from which another series is created and then plotted. More info available on MSDN.

  • This tag is also used in the context of questions on [pandas] Series. See the pandas tag wiki for more details.

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How to convert index of a pandas dataframe into a column

How to convert an index of a dataframe into a column? For example: gi ptt_loc 0 384444683 593 1 384444684 594 2 384444686 596 to index1 gi ptt_loc 0 0 384444683 593 1 1 …
msakya
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Combining two Series into a DataFrame in pandas

I have two Series s1 and s2 with the same (non-consecutive) indices. How do I combine s1 and s2 to being two columns in a DataFrame and keep one of the indices as a third column?
user7289
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Keep only date part when using pandas.to_datetime

I use pandas.to_datetime to parse the dates in my data. Pandas by default represents the dates with datetime64[ns] even though the dates are all daily only. I wonder whether there is an elegant/clever way to convert the dates to datetime.date or…
user1642513
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Conditional Replace Pandas

I have a DataFrame, and I want to replace the values in a particular column that exceed a value with zero. I had thought this was a way of achieving this: df[df.my_channel > 20000].my_channel = 0 If I copy the channel into a new data frame it's…
BMichell
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How to get the first column of a pandas DataFrame as a Series?

I tried: x=pandas.DataFrame(...) s = x.take([0], axis=1) And s gets a DataFrame, not a Series.
Yariv
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Pandas: change data type of Series to String

I use Pandas 'ver 0.12.0' with Python 2.7 and have a dataframe as below: df = pd.DataFrame({'id' : [123,512,'zhub1', 12354.3, 129, 753, 295, 610], 'colour': ['black', 'white','white','white', 'black',…
Zhubarb
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Convert pandas Series to DataFrame

I have a Pandas series sf: email email1@email.com [1.0, 0.0, 0.0] email2@email.com [2.0, 0.0, 0.0] email3@email.com [1.0, 0.0, 0.0] email4@email.com [4.0, 0.0, 0.0] email5@email.com [1.0, 0.0, 3.0] email6@email.com [1.0, 5.0,…
woshitom
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Strings in a DataFrame, but dtype is object

Why does Pandas tell me that I have objects, although every item in the selected column is a string — even after explicit conversion. This is my DataFrame: Int64Index: 56992 entries, 0 to 56991 Data columns…
Xiphias
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Convert pandas data frame to series

I'm somewhat new to pandas. I have a pandas data frame that is 1 row by 23 columns. I want to convert this into a series. I'm wondering what the most pythonic way to do this is? I've tried pd.Series(myResults) but it complains ValueError: cannot…
user1357015
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Pandas selecting by label sometimes return Series, sometimes returns DataFrame

In Pandas, when I select a label that only has one entry in the index I get back a Series, but when I select an entry that has more then one entry I get back a data frame. Why is that? Is there a way to ensure I always get back a data frame? In…
Job Evers
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Pandas: convert categories to numbers

Suppose I have a dataframe with countries that goes as: cc | temp US | 37.0 CA | 12.0 US | 35.0 AU | 20.0 I know that there is a pd.get_dummies function to convert the countries to 'one-hot encodings'. However, I wish to convert them to indices…
sachinruk
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Get first element of Series without knowing the index

Is there any way to access the first element of a Series without knowing its index? Let's say I have the following Series: import pandas as pd key='MCS096' SUBJECTS = pd.DataFrame( { "ID": pd.Series([146], index=[145]), "study":…
Hello lad
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Python: Pandas Series - Why use loc?

Why do we use 'loc' for pandas dataframes? it seems the following code with or without using loc both compile anr run at a simulular speed %timeit df_user1 = df.loc[df.user_id=='5561'] 100 loops, best of 3: 11.9 ms per loop or %timeit…
Runner Bean
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Floor or ceiling of a pandas series in python?

I have a pandas series series. If I want to get the element-wise floor or ceiling, is there a built in method or do I have to write the function and use apply? I ask because the data is big so I appreciate efficiency. Also this question has not…
wolfsatthedoor
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Extract values in Pandas value_counts()

Say we have used pandas dataframe[column].value_counts() which outputs: apple 5 sausage 2 banana 2 cheese 1 How do you extract the values in the order same as shown above from max to min ? e.g: [apple,sausage,banana,cheese]
JamesButterlips
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