Use the concat() method to concatenate two teradataml DataFrame objects along the index axis. The operation is performed by carrying out a database-style union or union all operation.
Examples Prerequisite
Assume the table "admissions_train" exists and a DataFrame "df" is created based on this table using the command:
>>> df = DataFrame("admissions_train")
>>> df masters gpa stats programming admitted id 22 yes 3.46 Novice Beginner 0 36 no 3.00 Advanced Novice 0 15 yes 4.00 Advanced Advanced 1 38 yes 2.65 Advanced Beginner 1 5 no 3.44 Novice Novice 0 17 no 3.83 Advanced Advanced 1 34 yes 3.85 Advanced Beginner 0 13 no 4.00 Advanced Novice 1 26 yes 3.57 Advanced Advanced 1 19 yes 1.98 Advanced Advanced 0
>>> df1 = df[df.gpa == 4].select(['id', 'stats', 'masters', 'gpa']) >>> df1 stats masters gpa id 13 Advanced no 4.0 29 Novice yes 4.0 15 Advanced yes 4.0
>>> df2 = df[df.gpa < 2].select(['id', 'stats', 'programming', 'admitted']) >>> df2 stats programming admitted id 24 Advanced Novice 1 19 Advanced Advanced 0
Example 1: Default behavior with default values for the optional arguments.
>>> # Default options >>> cdf = df1.concat(df2) >>> cdf stats masters gpa programming admitted id 19 Advanced None NaN Advanced 0 24 Advanced None NaN Novice 1 13 Advanced no 4.0 None None 29 Novice yes 4.0 None None 15 Advanced yes 4.0 None None
Example 2: concat() operation with 'join = inner'.
>>> cdf = df1.concat(df2, join='inner') >>> cdf stats id 19 Advanced 24 Advanced 13 Advanced 29 Novice 15 Advanced
Example 3: concat() operation with 'allow_duplicates=False'.
>>> # allow_duplicates = True (default) >>> cdf = df1.concat(df2) >>> cdf stats masters gpa programming admitted id 19 Advanced None NaN Advanced 0 24 Advanced None NaN Novice 1 13 Advanced no 4.0 None None 29 Novice yes 4.0 None None 15 Advanced yes 4.0 None None >>> cdf = cdf.concat(df2) >>> cdf stats masters gpa programming admitted id 19 Advanced None NaN Advanced 0 13 Advanced no 4.0 None None 24 Advanced None NaN Novice 1 24 Advanced None NaN Novice 1 19 Advanced None NaN Advanced 0 29 Novice yes 4.0 None None 15 Advanced yes 4.0 None None
>>> # allow_duplicates = False >>> cdf = cdf.concat(df2, allow_duplicates=False) >>> cdf stats masters gpa programming admitted id 19 Advanced None NaN Advanced 0 29 Novice yes 4.0 None None 24 Advanced None NaN Novice 1 15 Advanced yes 4.0 None None 13 Advanced no 4.0 None None
Example 4: concat() operation with 'sort=True'.
>>> cdf = df1.concat(df2, sort=True) >>> cdf admitted gpa masters programming stats id 19 0 NaN None Advanced Advanced 24 1 NaN None Novice Advanced 13 None 4.0 no None Advanced 29 None 4.0 yes None Novice 15 None 4.0 yes None Advanced