class pandas.Index[source]

Immutable ndarray implementing an ordered, sliceable set. The basic object storing axis labels for all pandas objects.

data : array-like (1-dimensional)
dtype : NumPy dtype (default: object)

If dtype is None, we find the dtype that best fits the data. If an actual dtype is provided, we coerce to that dtype if it’s safe. Otherwise, an error will be raised.

copy : bool

Make a copy of input ndarray

name : object

Name to be stored in the index

tupleize_cols : bool (default: True)

When True, attempt to create a MultiIndex if possible

See also

Index implementing a monotonic integer range.
Index of Categorical s.
A multi-level, or hierarchical, Index.
An Index of Interval s.
DatetimeIndex, TimedeltaIndex, PeriodIndex
Int64Index, UInt64Index, Float64Index


An Index instance can only contain hashable objects


>>> pd.Index([1, 2, 3])
Int64Index([1, 2, 3], dtype='int64')
>>> pd.Index(list('abc'))
Index(['a', 'b', 'c'], dtype='object')


T Return the transpose, which is by
array The ExtensionArray of the data backing this Series or Index.
asi8 Integer representation of the values.
base (DEPRECATED) Return the base object if the memory of the underlying data is shared.
data (DEPRECATED) Return the data pointer of the underlying data.
dtype Return the dtype object of the underlying data.
dtype_str (DEPRECATED) Return the dtype str of the underlying data.
hasnans Return if I have any nans; enables various perf speedups.
inferred_type Return a string of the type inferred from the values.
is_monotonic Alias for is_monotonic_increasing.
is_monotonic_decreasing Return if the index is monotonic decreasing (only equal or decreasing) values.
is_monotonic_increasing Return if the index is monotonic increasing (only equal or increasing) values.
is_unique Return if the index has unique values.
itemsize (DEPRECATED) Return the size of the dtype of the item of the underlying data.
nbytes Return the number of bytes in the underlying data.
ndim Number of dimensions of the underlying data, by definition 1.
nlevels Number of levels.
shape Return a tuple of the shape of the underlying data.
size Return the number of elements in the underlying data.
strides (DEPRECATED) Return the strides of the underlying data.
values Return an array representing the data in the Index.


all(self, \*args, \*\*kwargs) Return whether all elements are True.
any(self, \*args, \*\*kwargs) Return whether any element is True.
append(self, other) Append a collection of Index options together.
argmax(self[, axis, skipna]) Return an ndarray of the maximum argument indexer.
argmin(self[, axis, skipna]) Return a ndarray of the minimum argument indexer.
argsort(self, \*args, \*\*kwargs) Return the integer indices that would sort the index.
asof(self, label) Return the label from the index, or, if not present, the previous one.
asof_locs(self, where, mask) Find the locations (indices) of the labels from the index for every entry in the where argument.
astype(self, dtype[, copy]) Create an Index with values cast to dtypes.
contains(self, key) (DEPRECATED) Return a boolean indicating whether the provided key is in the index.
copy(self[, name, deep, dtype]) Make a copy of this object.
delete(self, loc) Make new Index with passed location(-s) deleted.
difference(self, other[, sort]) Return a new Index with elements from the index that are not in other.
drop(self, labels[, errors]) Make new Index with passed list of labels deleted.
drop_duplicates(self[, keep]) Return Index with duplicate values removed.
droplevel(self[, level]) Return index with requested level(s) removed.
dropna(self[, how]) Return Index without NA/NaN values
duplicated(self[, keep]) Indicate duplicate index values.
equals(self, other) Determine if two Index objects contain the same elements.
factorize(self[, sort, na_sentinel]) Encode the object as an enumerated type or categorical variable.
fillna(self[, value, downcast]) Fill NA/NaN values with the specified value
format(self[, name, formatter]) Render a string representation of the Index.
get_duplicates(self) (DEPRECATED) Extract duplicated index elements.
get_indexer(self, target[, method, limit, …]) Compute indexer and mask for new index given the current index.
get_indexer_for(self, target, \*\*kwargs) Guaranteed return of an indexer even when non-unique.
get_indexer_non_unique(self, target) Compute indexer and mask for new index given the current index.
get_level_values(self, level) Return an Index of values for requested level.
get_loc(self, key[, method, tolerance]) Get integer location, slice or boolean mask for requested label.
get_slice_bound(self, label, side, kind) Calculate slice bound that corresponds to given label.
get_value(self, series, key) Fast lookup of value from 1-dimensional ndarray.
get_values(self) (DEPRECATED) Return Index data as an numpy.ndarray.
groupby(self, values) Group the index labels by a given array of values.
holds_integer(self) Whether the type is an integer type.
identical(self, other) Similar to equals, but check that other comparable attributes are also equal.
insert(self, loc, item) Make new Index inserting new item at location.
intersection(self, other[, sort]) Form the intersection of two Index objects.
is_(self, other) More flexible, faster check like is but that works through views.
is_categorical(self) Check if the Index holds categorical data.
is_type_compatible(self, kind) Whether the index type is compatible with the provided type.
isin(self, values[, level]) Return a boolean array where the index values are in values.
isna(self) Detect missing values.
isnull(self) Detect missing values.
item(self) Return the first element of the underlying data as a python scalar.
join(self, other[, how, level, …]) Compute join_index and indexers to conform data structures to the new index.
map(self, mapper[, na_action]) Map values using input correspondence (a dict, Series, or function).
max(self[, axis, skipna]) Return the maximum value of the Index.
memory_usage(self[, deep]) Memory usage of the values
min(self[, axis, skipna]) Return the minimum value of the Index.
notna(self) Detect existing (non-missing) values.
notnull(self) Detect existing (non-missing) values.
nunique(self[, dropna]) Return number of unique elements in the object.
putmask(self, mask, value) Return a new Index of the values set with the mask.
ravel(self[, order]) Return an ndarray of the flattened values of the underlying data.
reindex(self, target[, method, level, …]) Create index with target’s values (move/add/delete values as necessary).
rename(self, name[, inplace]) Alter Index or MultiIndex name.
repeat(self, repeats[, axis]) Repeat elements of a Index.
searchsorted(self, value[, side, sorter]) Find indices where elements should be inserted to maintain order.
set_names(self, names[, level, inplace]) Set Index or MultiIndex name.
set_value(self, arr, key, value) Fast lookup of value from 1-dimensional ndarray.
shift(self[, periods, freq]) Shift index by desired number of time frequency increments.
slice_indexer(self[, start, end, step, kind]) For an ordered or unique index, compute the slice indexer for input labels and step.
slice_locs(self[, start, end, step, kind]) Compute slice locations for input labels.
sort(self, \*args, \*\*kwargs) Use sort_values instead.
sort_values(self[, return_indexer, ascending]) Return a sorted copy of the index.
sortlevel(self[, level, ascending, …]) For internal compatibility with with the Index API.
str alias of pandas.core.strings.StringMethods
summary(self[, name]) (DEPRECATED) Return a summarized representation.
symmetric_difference(self, other[, …]) Compute the symmetric difference of two Index objects.
take(self, indices[, axis, allow_fill, …]) Return a new Index of the values selected by the indices.
to_flat_index(self) Identity method.
to_frame(self[, index, name]) Create a DataFrame with a column containing the Index.
to_list(self) Return a list of the values.
to_native_types(self[, slicer]) Format specified values of self and return them.
to_numpy(self[, dtype, copy]) A NumPy ndarray representing the values in this Series or Index.
to_series(self[, index, name]) Create a Series with both index and values equal to the index keys useful with map for returning an indexer based on an index.
tolist(self) Return a list of the values.
transpose(self, \*args, \*\*kwargs) Return the transpose, which is by definition self.
union(self, other[, sort]) Form the union of two Index objects.
unique(self[, level]) Return unique values in the index.
value_counts(self[, normalize, sort, …]) Return a Series containing counts of unique values.
where(self, cond[, other]) Return an Index of same shape as self and whose corresponding entries are from self where cond is True and otherwise are from other.
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