How to add data in dataframe in python

DataFrame.append[other, ignore_index=False, verify_integrity=False, sort=False][source]#

Append rows of other to the end of caller, returning a new object.

Columns in other that are not in the caller are added as new columns.

ParametersotherDataFrame or Series/dict-like object, or list of these

The data to append.

ignore_indexbool, default False

If True, the resulting axis will be labeled 0, 1, …, n - 1.

verify_integritybool, default False

If True, raise ValueError on creating index with duplicates.

sortbool, default False

Sort columns if the columns of self and other are not aligned.

Changed in version 1.0.0: Changed to not sort by default.

ReturnsDataFrame

A new DataFrame consisting of the rows of caller and the rows of other.

See also

concat

General function to concatenate DataFrame or Series objects.

Notes

If a list of dict/series is passed and the keys are all contained in the DataFrame’s index, the order of the columns in the resulting DataFrame will be unchanged.

Iteratively appending rows to a DataFrame can be more computationally intensive than a single concatenate. A better solution is to append those rows to a list and then concatenate the list with the original DataFrame all at once.

Examples

>>> df = pd.DataFrame[[[1, 2], [3, 4]], columns=list['AB'], index=['x', 'y']]
>>> df
   A  B
x  1  2
y  3  4
>>> df2 = pd.DataFrame[[[5, 6], [7, 8]], columns=list['AB'], index=['x', 'y']]
>>> df.append[df2]
   A  B
x  1  2
y  3  4
x  5  6
y  7  8

With ignore_index set to True:

>>> df.append[df2, ignore_index=True]
   A  B
0  1  2
1  3  4
2  5  6
3  7  8

The following, while not recommended methods for generating DataFrames, show two ways to generate a DataFrame from multiple data sources.

Less efficient:

>>> df = pd.DataFrame[columns=['A']]
>>> for i in range[5]:
...     df = df.append[{'A': i}, ignore_index=True]
>>> df
   A
0  0
1  1
2  2
3  3
4  4

More efficient:

>>> pd.concat[[pd.DataFrame[[i], columns=['A']] for i in range[5]],
...           ignore_index=True]
   A
0  0
1  1
2  2
3  3
4  4

How do you add value to a data frame?

add[] method is used for addition of dataframe and other, element-wise [binary operator add]. Equivalent to dataframe + other, but with support to substitute a fill_value for missing data in one of the inputs. fill_value : [None or float value, default None] Fill missing [NaN] values with this value.

How do you add data to a column in a DataFrame?

In pandas you can add/append a new column to the existing DataFrame using DataFrame. insert[] method, this method updates the existing DataFrame with a new column. DataFrame. assign[] is also used to insert a new column however, this method returns a new Dataframe after adding a new column.

How do you add a value to a DataFrame column in Python?

You can use the assign[] function to add a new column to the end of a pandas DataFrame: df = df. assign[col_name=[value1, value2, value3, ...]]

What is SUM [] in pandas?

Pandas DataFrame sum[] Method The sum[] method adds all values in each column and returns the sum for each column. By specifying the column axis [ axis='columns' ], the sum[] method searches column-wise and returns the sum of each row.

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