add column to a dataframe r code example
Example 1: how to add a column to a pandas df
#using the insert function:
df.insert(location, column_name, list_of_values)
#example
df.insert(0, 'new_column', ['a','b','c'])
#explanation:
#put "new_column" as first column of the dataframe
#and puts 'a','b' and 'c' as values
#using array-like access:
df['new_column_name'] = value
#df stands for dataframe
Example 2: add column in spark dataframe
from pyspark.sql.functions import lit
df = sqlContext.createDataFrame(
[(1, "a", 23.0), (3, "B", -23.0)], ("x1", "x2", "x3"))
df_with_x4 = df.withColumn("x4", lit(0))
df_with_x4.show()
## +---+---+-----+---+
## | x1| x2| x3| x4|
## +---+---+-----+---+
## | 1| a| 23.0| 0|
## | 3| B|-23.0| 0|
## +---+---+-----+---+