Joins and Binds

Combine tables by key columns (joins) or by stacking (binds).

`df_inner_join` (T1, T2, key) — Function

Join two tables on a key column, keeping only rows with matching keys in both tables.

Examples

(%i1) T1 : df_table(["id", "name"],
                     [df_string_column(["1","2","3"]),
                      df_string_column(["Alice","Bob","Charlie"])])$
(%i2) T2 : df_table(["id", "score"],
                     [df_string_column(["1","2"]),
                      ndarray([90.0, 80.0])])$
(%i3) df_inner_join(T1, T2, "id");
(%o3)              df_table: 2 rows x 3 cols

See also: df_left_join, df_bind_cols

`df_left_join` (T1, T2, key) — Function

Join two tables on a key column, keeping all rows from the left table. Unmatched right columns are filled with 0 (numeric) or “” (string).

Examples

(%i1) df_left_join(T1, T2, "id");
(%o1)              df_table: 3 rows x 3 cols

`df_bind_rows` (T1, T2) — Function

Stack two tables vertically. Column names must match exactly.

Examples

(%i1) A : df_table(["x"], [ndarray([1.0, 2.0])])$
(%i2) B : df_table(["x"], [ndarray([3.0, 4.0])])$
(%i3) df_table_shape(df_bind_rows(A, B));
(%o3)                        [4, 1]

`df_bind_cols` (T1, T2) — Function

Stack two tables horizontally. Row counts must match and column names must not overlap.

Examples

(%i1) X : df_table(["x"], [ndarray([1.0, 2.0])])$
(%i2) Y : df_table(["y"], [ndarray([3.0, 4.0])])$
(%i3) df_table_names(df_bind_cols(X, Y));
(%o3)                        [x, y]

See also: df_bind_rows, df_inner_join

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