id
stringlengths
7
25
category
stringclasses
4 values
instruction
stringlengths
30
154
setup
stringlengths
32
144
expected
unknown
solution
stringlengths
18
232
oc_col_to_list
output_convention
Return the 'a' column as a plain Python list.
df = pl.DataFrame({'a': [1, 2, 3]})
[ 1, 2, 3 ]
result = df['a'].to_list()
oc_scalar_sum
output_convention
Return the sum of the 'v' column as a plain integer.
df = pl.DataFrame({'v': [1, 2, 3]})
6
result = int(df['v'].sum())
oc_first_value
output_convention
Return the value in the first row of column 'x' as a plain integer.
df = pl.DataFrame({'x': [42, 7, 9]})
42
result = int(df['x'][0])
oc_row_count
output_convention
Return the number of rows as a plain integer.
df = pl.DataFrame({'a': [1, 2, 3, 4]})
4
result = df.height
oc_column_names
output_convention
Return the list of column names.
df = pl.DataFrame({'name': ['a'], 'age': [1]})
[ "name", "age" ]
result = df.columns
oc_kv_dict
output_convention
Return a dict mapping each value of 'k' to its value of 'v'.
df = pl.DataFrame({'k': ['a', 'b'], 'v': [1, 2]})
{ "a": 1, "b": 2 }
result = dict(zip(df['k'].to_list(), df['v'].to_list()))
oc_rows_as_dicts
output_convention
Return every row as a list of dicts.
df = pl.DataFrame({'a': [1, 2], 'b': ['x', 'y']})
[ { "a": 1, "b": "x" }, { "a": 2, "b": "y" } ]
result = df.to_dicts()
oc_max_float
output_convention
Return the maximum value of 'v' as a plain float.
df = pl.DataFrame({'v': [1.5, 9.25, 3.0]})
9.25
result = float(df['v'].max())
oc_mean_rounded
output_convention
Return the mean of 'v' rounded to 2 decimal places, as a plain float.
df = pl.DataFrame({'v': [1.0, 2.0, 4.0]})
2.33
result = round(float(df['v'].mean()), 2)
oc_any_bool
output_convention
Return True if any value in 'v' is greater than 10, otherwise False, as a plain bool.
df = pl.DataFrame({'v': [3, 15, 7]})
true
result = bool((df['v'] > 10).any())
oc_first_row_dict
output_convention
Return the first row as a dict.
df = pl.DataFrame({'a': [1, 2], 'b': ['x', 'y']})
{ "a": 1, "b": "x" }
result = df.head(1).to_dicts()[0]
oc_distinct_count
output_convention
Return the number of distinct values in 'c' as a plain integer.
df = pl.DataFrame({'c': ['a', 'b', 'a']})
2
result = int(df['c'].n_unique())
pt_sort_desc
pandas_trap
Sort rows by 'score' from highest to lowest and return the 'name' column as a list.
df = pl.DataFrame({'name': ['x', 'y', 'z'], 'score': [7, 12, 9]})
[ "y", "z", "x" ]
result = df.sort('score', descending=True)['name'].to_list()
pt_groupby_sum
pandas_trap
Group by 'team', sum 'pts', and return a dict mapping team to its total.
df = pl.DataFrame({'team': ['a', 'b', 'a'], 'pts': [3, 5, 2]})
{ "a": 5, "b": 5 }
g = df.group_by('team').agg(pl.col('pts').sum()) result = dict(zip(g['team'].to_list(), g['pts'].to_list()))
pt_fill_nulls
pandas_trap
Replace null values in 'v' with 0 and return 'v' as a list.
df = pl.DataFrame({'v': [1, None, 3]})
[ 1, 0, 3 ]
result = df.with_columns(pl.col('v').fill_null(0))['v'].to_list()
pt_cast_type
pandas_trap
Convert column 'a' to 64-bit integers and return it as a list.
df = pl.DataFrame({'a': ['1', '2', '3']})
[ 1, 2, 3 ]
result = df.with_columns(pl.col('a').cast(pl.Int64))['a'].to_list()
pt_merge_join
pandas_trap
Inner join df and df2 on 'id', sort by 'id' ascending, and return the 'city' column as a list.
df = pl.DataFrame({'id': [1, 2, 3], 'n': ['a', 'b', 'c']}) df2 = pl.DataFrame({'id': [2, 3, 4], 'city': ['x', 'y', 'z']})
[ "x", "y" ]
result = df.join(df2, on='id', how='inner').sort('id')['city'].to_list()
pt_drop_duplicates
pandas_trap
Remove duplicate rows and return the remaining rows as a list of dicts, ordered by 'a' ascending.
df = pl.DataFrame({'a': [1, 1, 2], 'b': ['x', 'x', 'y']})
[ { "a": 1, "b": "x" }, { "a": 2, "b": "y" } ]
result = df.unique().sort('a').to_dicts()
pt_isin_filter
pandas_trap
Keep only rows where 'c' is either 'b' or 'd', and return 'c' as a list.
df = pl.DataFrame({'c': ['a', 'b', 'c', 'd']})
[ "b", "d" ]
result = df.filter(pl.col('c').is_in(['b', 'd']))['c'].to_list()
pt_value_counts
pandas_trap
Count how many times each value appears in 'c' and return a dict mapping value to count.
df = pl.DataFrame({'c': ['a', 'b', 'a', 'a']})
{ "a": 3, "b": 1 }
g = df.group_by('c').agg(pl.len().alias('n')) result = dict(zip(g['c'].to_list(), g['n'].to_list()))
pt_rename_column
pandas_trap
Rename column 'old' to 'new' and return the list of column names.
df = pl.DataFrame({'old': [1, 2]})
[ "new" ]
result = df.rename({'old': 'new'}).columns
pt_string_upper
pandas_trap
Convert every value in 's' to uppercase and return 's' as a list.
df = pl.DataFrame({'s': ['ab', 'cd']})
[ "AB", "CD" ]
result = df.with_columns(pl.col('s').str.to_uppercase())['s'].to_list()
pt_filter_select_cols
pandas_trap
Keep only rows where 'a' is greater than 1, and return only columns 'a' and 'c' as a list of dicts.
df = pl.DataFrame({'a': [1, 2, 3], 'b': [4, 5, 6], 'c': [7, 8, 9]})
[ { "a": 2, "c": 8 }, { "a": 3, "c": 9 } ]
result = df.filter(pl.col('a') > 1).select(['a', 'c']).to_dicts()
pt_nunique_per_group
pandas_trap
For each group in 'g', count the distinct values of 'v'. Return a dict mapping group to that count.
df = pl.DataFrame({'g': ['x', 'x', 'y'], 'v': [1, 1, 2]})
{ "x": 1, "y": 1 }
g = df.group_by('g').agg(pl.col('v').n_unique().alias('n')) result = dict(zip(g['g'].to_list(), g['n'].to_list()))
sa_with_columns
stale_api
Add a column 'b' equal to 'a' multiplied by 2, and return 'b' as a list.
df = pl.DataFrame({'a': [1, 2]})
[ 2, 4 ]
result = df.with_columns((pl.col('a') * 2).alias('b'))['b'].to_list()
sa_row_count_expr
stale_api
Count the number of rows per group in 'g'. Return a dict mapping group to count.
df = pl.DataFrame({'g': ['a', 'a', 'b']})
{ "a": 2, "b": 1 }
g = df.group_by('g').agg(pl.len().alias('n')) result = dict(zip(g['g'].to_list(), g['n'].to_list()))
sa_cum_sum
stale_api
Return the running cumulative sum of 'v' as a list.
df = pl.DataFrame({'v': [1, 2, 3]})
[ 1, 3, 6 ]
result = df.with_columns(pl.col('v').cum_sum().alias('c'))['c'].to_list()
sa_gather
stale_api
Return the values of 'v' at row positions 0 and 2, as a list.
df = pl.DataFrame({'v': [10, 20, 30, 40]})
[ 10, 30 ]
result = df['v'].gather([0, 2]).to_list()
sa_str_length
stale_api
Return the character length of each value in 's' as a list.
df = pl.DataFrame({'s': ['ab', 'abcd']})
[ 2, 4 ]
result = df.with_columns(pl.col('s').str.len_chars().alias('n'))['n'].to_list()
sa_rank_descending
stale_api
Rank the values in 'v' from highest to lowest, where 1 is the highest. Return the ranks as a list in original row order.
df = pl.DataFrame({'v': [5, 9, 2]})
[ 2, 1, 3 ]
result = df.with_columns(pl.col('v').rank(method='min', descending=True).cast(pl.Int64).alias('r'))['r'].to_list()
sa_map_elements
stale_api
Apply a Python function to each value of 'n' that returns the value squared, and return the results as a list.
df = pl.DataFrame({'n': [1, 2, 3]})
[ 1, 4, 9 ]
result = df.with_columns(pl.col('n').map_elements(lambda x: x * x, return_dtype=pl.Int64).alias('sq'))['sq'].to_list()
sa_list_namespace
stale_api
Column 'xs' holds lists. Return the length of each list as a list of integers.
df = pl.DataFrame({'xs': [[1, 2], [3, 4, 5]]})
[ 2, 3 ]
result = df.with_columns(pl.col('xs').list.len().alias('n'))['n'].to_list()
sa_explode
stale_api
Expand column 'xs' so each list element becomes its own row, then return 'xs' as a list.
df = pl.DataFrame({'g': ['a', 'b'], 'xs': [[1, 2], [3]]})
[ 1, 2, 3 ]
result = df.explode('xs')['xs'].to_list()
sa_top_k
stale_api
Return the 2 largest values in 'v', sorted from highest to lowest, as a list.
df = pl.DataFrame({'v': [5, 1, 9, 3]})
[ 9, 5 ]
result = df['v'].top_k(2).sort(descending=True).to_list()
sa_shift_fill
stale_api
Shift the 'v' column down by one position, filling the first slot with 0. Return as a list.
df = pl.DataFrame({'v': [1, 2, 3]})
[ 0, 1, 2 ]
result = df.with_columns(pl.col('v').shift(1, fill_value=0).alias('s'))['s'].to_list()
sa_pivot
stale_api
Pivot the table so rows come from 'r', columns from 'c', and cell values from 'v'. Return the result as a list of dicts sorted by 'r'.
df = pl.DataFrame({'r': ['x', 'x', 'y'], 'c': ['a', 'b', 'a'], 'v': [1, 2, 3]})
[ { "r": "x", "a": 1, "b": 2 }, { "r": "y", "a": 3, "b": null } ]
result = df.pivot(on='c', index='r', values='v').sort('r').to_dicts()
h_rank_over_group
hard
Within each 'grp', rank rows by 'val' descending where 1 is the highest. Return the ranks as a list in original row order.
df = pl.DataFrame({'grp': ['a', 'a', 'b', 'b'], 'val': [5, 9, 2, 7]})
[ 2, 1, 2, 1 ]
result = df.with_columns(pl.col('val').rank(method='min', descending=True).over('grp').cast(pl.Int64).alias('r'))['r'].to_list()
h_multi_key_join
hard
Inner join df and df2 on both 'a' and 'b'. Sort by 'a' ascending and return the 'w' column as a list.
df = pl.DataFrame({'a': [1, 1, 2], 'b': ['x', 'y', 'x'], 'v': [10, 20, 30]}) df2 = pl.DataFrame({'a': [1, 2], 'b': ['x', 'x'], 'w': [100, 200]})
[ 100, 200 ]
result = df.join(df2, on=['a', 'b'], how='inner').sort('a')['w'].to_list()
h_conditional_sum
hard
For each group in 'g', sum only the 'v' values where 'ok' is True. Return a dict mapping group to that sum.
df = pl.DataFrame({'g': ['a', 'a', 'b'], 'v': [1, 5, 7], 'ok': [True, False, True]})
{ "a": 1, "b": 7 }
g = df.group_by('g').agg(pl.col('v').filter(pl.col('ok')).sum().alias('s')) result = dict(zip(g['g'].to_list(), g['s'].to_list()))
h_top_n_per_group
hard
For each group in 'g', keep the 2 rows with the largest 'v'. Return the kept 'v' values as a list sorted ascending.
df = pl.DataFrame({'g': ['a', 'a', 'a', 'b', 'b'], 'v': [3, 9, 5, 1, 8]})
[ 1, 5, 8, 9 ]
r = df.filter(pl.col('v').rank(method='ordinal', descending=True).over('g') <= 2) result = sorted(r['v'].to_list())
h_rolling_mean
hard
Compute the rolling mean of 'v' over a window of 2 rows. Return it as a list; the first entry should be null.
df = pl.DataFrame({'v': [1.0, 2.0, 3.0, 4.0]})
[ null, 1.5, 2.5, 3.5 ]
result = df.with_columns(pl.col('v').rolling_mean(window_size=2).alias('m'))['m'].to_list()
h_cumsum_by_group
hard
Compute a cumulative sum of 'v' within each group in 'g'. Return as a list in original row order.
df = pl.DataFrame({'g': ['a', 'a', 'b', 'b'], 'v': [1, 2, 10, 20]})
[ 1, 3, 10, 30 ]
result = df.with_columns(pl.col('v').cum_sum().over('g').alias('c'))['c'].to_list()
h_lag_diff
hard
For each row compute the difference between 'v' and the previous row's 'v'. The first row should be null. Return as a list.
df = pl.DataFrame({'v': [10, 13, 18]})
[ null, 3, 5 ]
result = df.with_columns((pl.col('v') - pl.col('v').shift(1)).alias('d'))['d'].to_list()
h_multi_agg
hard
Group by 'k'. For each group compute the mean of 'v' and the number of rows. Return a dict mapping k to a two-element list [mean, count].
df = pl.DataFrame({'k': ['a', 'a', 'b'], 'v': [1.0, 3.0, 10.0]})
{ "a": [ 2, 2 ], "b": [ 10, 1 ] }
g = df.group_by('k').agg([pl.col('v').mean().alias('m'), pl.len().alias('n')]) result = {k: [m, n] for k, m, n in zip(g['k'].to_list(), g['m'].to_list(), g['n'].to_list())}
h_split_count
hard
Each value in 'tags' is a comma-separated string. Return the total number of tags across all rows as a plain integer.
df = pl.DataFrame({'tags': ['a,b', 'c', 'd,e,f']})
6
result = int(df.with_columns(pl.col('tags').str.split(',').list.len().alias('n'))['n'].sum())
h_when_then_chain
hard
Label each value in 'n' as 'low' if under 10, 'mid' if under 100, otherwise 'high'. Return the labels as a list.
df = pl.DataFrame({'n': [5, 9, 12, 98, 103]})
[ "low", "low", "mid", "mid", "high" ]
result = df.with_columns(pl.when(pl.col('n') < 10).then(pl.lit('low')).when(pl.col('n') < 100).then(pl.lit('mid')).otherwise(pl.lit('high')).alias('l'))['l'].to_list()
h_filter_by_group_size
hard
Keep only the rows whose group in 'g' contains more than one row, then return the 'g' values of those rows as a list sorted ascending.
df = pl.DataFrame({'g': ['a', 'a', 'b', 'c'], 'v': [1, 2, 5, 9]})
[ "a", "a" ]
result = sorted(df.filter(pl.len().over('g') > 1)['g'].to_list())
h_anti_join
hard
Return the 'id' values in df that do NOT appear in df2, sorted ascending, as a list.
df = pl.DataFrame({'id': [1, 2, 3]}) df2 = pl.DataFrame({'id': [2]})
[ 1, 3 ]
result = df.join(df2, on='id', how='anti').sort('id')['id'].to_list()
oc2_sum_float
output_convention
Return the sum of 'v' as a plain float.
df = pl.DataFrame({'v': [1.5, 2.25, 3.0]})
6.75
result = float(df['v'].sum())
oc2_n_columns
output_convention
Return the number of columns as a plain integer.
df = pl.DataFrame({'a': [1], 'b': [2], 'c': [3]})
3
result = len(df.columns)
oc2_shape_list
output_convention
Return the table's shape as a two-element list [rows, columns].
df = pl.DataFrame({'a': [1, 2, 3], 'b': [4, 5, 6]})
[ 3, 2 ]
result = [df.height, df.width]
oc2_null_count
output_convention
Return how many nulls are in column 'v', as a plain integer.
df = pl.DataFrame({'v': [1, None, 3, None]})
2
result = int(df['v'].null_count())
oc2_last_row_dict
output_convention
Return the last row as a dict.
df = pl.DataFrame({'a': [1, 2, 3], 'b': ['x', 'y', 'z']})
{ "a": 3, "b": "z" }
result = df.tail(1).to_dicts()[0]
oc2_nth_value
output_convention
Return the value in row index 2 of column 'v' as a plain integer.
df = pl.DataFrame({'v': [10, 20, 30, 40]})
30
result = int(df['v'][2])
oc2_median_float
output_convention
Return the median of 'v' as a plain float.
df = pl.DataFrame({'v': [1.0, 5.0, 3.0]})
3
result = float(df['v'].median())
oc2_all_bool
output_convention
Return True if every value in 'v' is greater than 0, otherwise False, as a plain bool.
df = pl.DataFrame({'v': [3, 8, 1]})
true
result = bool((df['v'] > 0).all())
oc2_all_bool_false
output_convention
Return True if every value in 'v' is greater than 5, otherwise False, as a plain bool.
df = pl.DataFrame({'v': [3, 8, 1]})
false
result = bool((df['v'] > 5).all())
oc2_pairs
output_convention
Return a list of two-element lists pairing each 'k' with its 'v', in row order.
df = pl.DataFrame({'k': ['a', 'b'], 'v': [1, 2]})
[ [ "a", 1 ], [ "b", 2 ] ]
result = [[k, v] for k, v in zip(df['k'].to_list(), df['v'].to_list())]
oc2_dtypes_str
output_convention
Return the data type names of the columns as a list of strings, in column order.
df = pl.DataFrame({'a': [1], 'b': ['x']})
[ "Int64", "String" ]
result = [str(d) for d in df.dtypes]
oc2_unique_sorted_list
output_convention
Return the distinct values of 'c' sorted ascending, as a list.
df = pl.DataFrame({'c': [3, 1, 3, 2]})
[ 1, 2, 3 ]
result = sorted(df['c'].unique().to_list())
oc2_min_int
output_convention
Return the smallest value in 'v' as a plain integer.
df = pl.DataFrame({'v': [7, 2, 9]})
2
result = int(df['v'].min())
oc2_std_rounded
output_convention
Return the standard deviation of 'v' rounded to 3 decimal places, as a plain float.
df = pl.DataFrame({'v': [2.0, 4.0, 4.0, 4.0, 5.0, 5.0, 7.0, 9.0]})
2.138
result = round(float(df['v'].std()), 3)
oc2_is_empty
output_convention
Return True if the table has no rows, otherwise False, as a plain bool.
df = pl.DataFrame({'a': [1, 2]})
false
result = df.height == 0
oc2_column_as_strings
output_convention
Return the values of 'n' converted to strings, as a list.
df = pl.DataFrame({'n': [1, 2, 3]})
[ "1", "2", "3" ]
result = [str(x) for x in df['n'].to_list()]
oc2_sum_two_cols
output_convention
Return the combined total of every value in columns 'a' and 'b', as a plain integer.
df = pl.DataFrame({'a': [1, 2], 'b': [10, 20]})
33
result = int(df['a'].sum() + df['b'].sum())
oc2_count_matching
output_convention
Return how many rows have 'v' greater than 5, as a plain integer.
df = pl.DataFrame({'v': [3, 8, 6, 1]})
2
result = int((df['v'] > 5).sum())
pt2_between
pandas_trap
Keep only rows where 'v' is between 10 and 30 inclusive, and return 'v' as a list.
df = pl.DataFrame({'v': [5, 10, 22, 30, 41]})
[ 10, 22, 30 ]
result = df.filter(pl.col('v').is_between(10, 30))['v'].to_list()
pt2_startswith
pandas_trap
Keep only rows where 'sku' starts with 'A', and return 'sku' as a list.
df = pl.DataFrame({'sku': ['A1', 'B2', 'A3']})
[ "A1", "A3" ]
result = df.filter(pl.col('sku').str.starts_with('A'))['sku'].to_list()
pt2_str_replace
pandas_trap
Replace every '-' with '_' in column 's' and return 's' as a list.
df = pl.DataFrame({'s': ['a-b', 'c-d']})
[ "a_b", "c_d" ]
result = df.with_columns(pl.col('s').str.replace_all('-', '_'))['s'].to_list()
pt2_dropna
pandas_trap
Remove rows where 'v' is null and return 'v' as a list.
df = pl.DataFrame({'v': [1, None, 3]})
[ 1, 3 ]
result = df.drop_nulls('v')['v'].to_list()
pt2_abs
pandas_trap
Return the absolute value of every entry in 'v', as a list.
df = pl.DataFrame({'v': [-3, 4, -5]})
[ 3, 4, 5 ]
result = df.with_columns(pl.col('v').abs().alias('o'))['o'].to_list()
pt2_round_col
pandas_trap
Round every value in 'v' to 1 decimal place and return 'v' as a list.
df = pl.DataFrame({'v': [1.24, 3.68]})
[ 1.2, 3.7 ]
result = df.with_columns(pl.col('v').round(1))['v'].to_list()
pt2_clip
pandas_trap
Limit every value in 'v' to a maximum of 10, leaving smaller values unchanged. Return 'v' as a list.
df = pl.DataFrame({'v': [4, 15, 9, 22]})
[ 4, 10, 9, 10 ]
result = df.with_columns(pl.col('v').clip(upper_bound=10))['v'].to_list()
pt2_sort_two_cols
pandas_trap
Sort by 'g' ascending then 'v' descending, and return 'v' as a list.
df = pl.DataFrame({'g': ['b', 'a', 'a'], 'v': [1, 5, 9]})
[ 9, 5, 1 ]
result = df.sort(['g', 'v'], descending=[False, True])['v'].to_list()
pt2_concat_rows
pandas_trap
Stack df on top of df2 into one table and return column 'a' as a list.
df = pl.DataFrame({'a': [1, 2]}) df2 = pl.DataFrame({'a': [3]})
[ 1, 2, 3 ]
result = pl.concat([df, df2])['a'].to_list()
pt2_groupby_two_keys
pandas_trap
Group by both 'g' and 'h', sum 'v', and return the summed values sorted ascending as a list.
df = pl.DataFrame({'g': ['a', 'a', 'b'], 'h': ['x', 'y', 'x'], 'v': [1, 2, 7]})
[ 1, 2, 7 ]
g = df.group_by(['g', 'h']).agg(pl.col('v').sum()) result = sorted(g['v'].to_list())
pt2_idxmax
pandas_trap
Return the row index of the largest value in 'v', as a plain integer.
df = pl.DataFrame({'v': [4, 19, 7]})
1
result = int(df['v'].arg_max())
pt2_head_tail
pandas_trap
Return the last 2 values of 'v' as a list, in row order.
df = pl.DataFrame({'v': [1, 2, 3, 4]})
[ 3, 4 ]
result = df.tail(2)['v'].to_list()
pt2_mean_per_column
pandas_trap
Return a dict mapping each column name to the mean of that column.
df = pl.DataFrame({'a': [2.0, 4.0], 'b': [10.0, 20.0]})
{ "a": 3, "b": 15 }
result = {c: float(df[c].mean()) for c in df.columns}
pt2_nlargest
pandas_trap
Return the 2 largest values of 'v', sorted from highest to lowest, as a list.
df = pl.DataFrame({'v': [5, 22, 13, 8]})
[ 22, 13 ]
result = df.sort('v', descending=True).head(2)['v'].to_list()
pt2_where_mask
pandas_trap
Replace every value in 'v' below 0 with 0, leaving others unchanged. Return 'v' as a list.
df = pl.DataFrame({'v': [-4, 3, -1, 8]})
[ 0, 3, 0, 8 ]
result = df.with_columns(pl.when(pl.col('v') < 0).then(0).otherwise(pl.col('v')).alias('v'))['v'].to_list()
pt2_duplicated
pandas_trap
Return the values of 'v' that appear more than once, sorted ascending, as a list.
df = pl.DataFrame({'v': [1, 2, 2, 3, 3, 3]})
[ 2, 3 ]
g = df.group_by('v').agg(pl.len().alias('n')).filter(pl.col('n') > 1) result = sorted(g['v'].to_list())
pt2_select_dtypes
pandas_trap
Return the names of the columns that hold text values, as a list.
df = pl.DataFrame({'a': [1], 'b': ['x'], 'c': ['y']})
[ "b", "c" ]
result = [c for c, d in zip(df.columns, df.dtypes) if d == pl.String]
pt2_astype_float
pandas_trap
Convert 'a' to floating point numbers and return it as a list.
df = pl.DataFrame({'a': [1, 2]})
[ 1, 2 ]
result = df.with_columns(pl.col('a').cast(pl.Float64))['a'].to_list()
sa2_with_row_index
stale_api
Add a column called 'idx' holding each row's position starting at 0, and return 'idx' as a list.
df = pl.DataFrame({'v': [9, 8, 7]})
[ 0, 1, 2 ]
result = df.with_row_index('idx')['idx'].cast(pl.Int64).to_list()
sa2_cum_max
stale_api
Return the running maximum of 'v' as a list.
df = pl.DataFrame({'v': [3, 1, 7, 5]})
[ 3, 3, 7, 7 ]
result = df.with_columns(pl.col('v').cum_max().alias('o'))['o'].to_list()
sa2_cum_prod
stale_api
Return the running product of 'v' as a list.
df = pl.DataFrame({'v': [2, 3, 2]})
[ 2, 6, 12 ]
result = df.with_columns(pl.col('v').cum_prod().alias('o'))['o'].to_list()
sa2_arg_sort
stale_api
Return the row positions that would sort 'v' in ascending order, as a list.
df = pl.DataFrame({'v': [30, 10, 20]})
[ 1, 2, 0 ]
result = df['v'].arg_sort().cast(pl.Int64).to_list()
sa2_strip_chars
stale_api
Remove leading and trailing whitespace from every value in 's' and return 's' as a list.
df = pl.DataFrame({'s': [' a ', ' b']})
[ "a", "b" ]
result = df.with_columns(pl.col('s').str.strip_chars())['s'].to_list()
sa2_bottom_k
stale_api
Return the 2 smallest values of 'v', sorted ascending, as a list.
df = pl.DataFrame({'v': [8, 2, 5, 9]})
[ 2, 5 ]
result = df['v'].bottom_k(2).sort().to_list()
sa2_concat_str
stale_api
Join columns 'a' and 'b' into one string per row separated by '-', and return the results as a list.
df = pl.DataFrame({'a': ['x', 'y'], 'b': ['1', '2']})
[ "x-1", "y-2" ]
result = df.with_columns(pl.concat_str([pl.col('a'), pl.col('b')], separator='-').alias('o'))['o'].to_list()
sa2_is_duplicated
stale_api
Return a list of booleans saying, for each row, whether its 'v' value occurs more than once.
df = pl.DataFrame({'v': [1, 2, 1]})
[ true, false, true ]
result = df['v'].is_duplicated().to_list()
sa2_unique_maintain_order
stale_api
Return the distinct values of 'c' in the order they first appear, as a list.
df = pl.DataFrame({'c': ['b', 'a', 'b', 'c']})
[ "b", "a", "c" ]
result = df['c'].unique(maintain_order=True).to_list()
sa2_str_to_lower
stale_api
Convert every value in 's' to lowercase and return 's' as a list.
df = pl.DataFrame({'s': ['AB', 'Cd']})
[ "ab", "cd" ]
result = df.with_columns(pl.col('s').str.to_lowercase())['s'].to_list()
sa2_list_sum
stale_api
Column 'xs' holds lists of numbers. Return the sum of each list, as a list of integers.
df = pl.DataFrame({'xs': [[1, 2], [3, 4, 5]]})
[ 3, 12 ]
result = df.with_columns(pl.col('xs').list.sum().alias('o'))['o'].to_list()
sa2_list_first
stale_api
Column 'xs' holds lists. Return the first element of each list, as a list.
df = pl.DataFrame({'xs': [[7, 2], [4, 9, 1]]})
[ 7, 4 ]
result = df.with_columns(pl.col('xs').list.first().alias('o'))['o'].to_list()
sa2_str_contains_literal
stale_api
Keep only rows where 'p' contains the literal text '.csv', and return 'p' as a list.
df = pl.DataFrame({'p': ['a.csv', 'b.txt', 'cxcsv']})
[ "a.csv" ]
result = df.filter(pl.col('p').str.contains('.csv', literal=True))['p'].to_list()
sa2_replace_values
stale_api
Replace the value 2 with 99 in column 'v', leaving other values unchanged. Return 'v' as a list.
df = pl.DataFrame({'v': [1, 2, 3, 2]})
[ 1, 99, 3, 99 ]
result = df.with_columns(pl.col('v').replace(2, 99))['v'].to_list()
sa2_diff
stale_api
Return the difference between each value of 'v' and the previous one. The first entry should be null.
df = pl.DataFrame({'v': [10, 14, 9]})
[ null, 4, -5 ]
result = df.with_columns(pl.col('v').diff().alias('o'))['o'].to_list()
sa2_n_unique_expr
stale_api
Return the number of distinct values in 'c' as a plain integer, computed with a polars expression.
df = pl.DataFrame({'c': ['a', 'b', 'a', 'c']})
3
result = int(df.select(pl.col('c').n_unique()).item())