DataFrame class

DataFrame for all sorts of data accumulation, analysis & manipulation and collection tasks.

Row access is granted through regular indexing, as DataFrame extends the data matrix of shape (rows x columns). Columns may be accessed via dataframe('columnName').

Inheritance

Constructors

DataFrame.empty(): Returns an empty dataframe.
DataFrame.fromNamesAndData(List<String> columnNames, DataMatrix data): Build a dataframe from specified columnNames and data. The data is expected to be of the shape (rows x columns).
factory
DataFrame.fromRowMaps(List<RecordRowMap> rowMaps): Builds a dataframe from a list of rowMaps, e.g. [{'col1': 420, 'col2': 69}, {'col1': 666, 'col2': 1470}].

Properties

columnNames → List<String>: no setter
first ↔ RecordRow: The first element.
getter/setter pairinherited
hashCode → int: Returns hashCode accounting for both the data and _trackedColumnNames
no setteroverride
isEmpty → bool: Whether this collection has no elements.
no setterinherited
isNotEmpty → bool: Whether this collection has at least one element.
no setterinherited
iterator → Iterator<RecordRow>: A new Iterator that allows iterating the elements of this Iterable.
no setterinherited
l → List<RecordRow>: finalinherited
last ↔ RecordRow: The last element.
getter/setter pairinherited
length ↔ int: The number of objects in this list.
getter/setter pairinherited
nColumns → int: Returns the number of columns currently held by the instance.
no setter
reversed → Iterable<RecordRow>: An Iterable of the objects in this list in reverse order.
no setterinherited
runtimeType → Type: A representation of the runtime type of the object.
no setterinherited
shape → List<int>: Returns an unmodifiable list of nRows, nColumns.
no setter
single → RecordRow: Checks that this iterable has only one element, and returns that element.
no setterinherited

Methods

add(RecordRow element) → void: Adds value to the end of this list, extending the length by one.
inherited
addAll(Iterable<RecordRow> iterable) → void: Appends all objects of iterable to the end of this list.
inherited
addColumn(String name, RecordCol records) → void: Add a new column to the end of the dataframe. The records have to be of the same length as the dataframe.
addRowFromMap(RecordRowMap rowMap) → void: Add a new row represented by rowMap of the structure {columnName: record} to the end of the dataframe.
any(bool test(RecordRow element)) → bool: Checks whether any element of this iterable satisfies test.
inherited
asMap() → Map<int, RecordRow>: An unmodifiable Map view of this list.
inherited
call<T>(String colName, {int start = 0, int? end}) → Column<T>: Enables (typed) column access.
cast<R>() → List<R>: Returns a view of this list as a list of R instances.
inherited
clear() → void: Removes all objects from this list; the length of the list becomes zero.
inherited
columnAsIterable<T>(String colName, {int start = 0, int? end}) → Iterable<T>: Returns an iterable over the records of a column sliced as per start and end.
columnIndex(String colName) → int: Accesses column index in O(1).
columnMap() → Map<String, RecordCol>: Returns a {columnName: columnData} representation.
columns() → Iterable<Column>: Returns an iterable over all columns.
contains(Object? element) → bool: Whether the collection contains an element equal to element.
inherited
copy() → DataFrame: Returns a copy of the instance.
elementAt(int index) → RecordRow: Returns the indexth element.
inherited
every(bool test(RecordRow element)) → bool: Checks whether every element of this iterable satisfies test.
inherited
expand<T>(Iterable<T> f(RecordRow element)) → Iterable<T>: Expands each element of this Iterable into zero or more elements.
inherited
fillRange(int start, int end, [RecordRow? fill]) → void: Overwrites a range of elements with fillValue.
inherited
firstWhere(bool test(RecordRow element), {RecordRow orElse()?}) → RecordRow: The first element that satisfies the given predicate test.
inherited
fold<T>(T initialValue, T combine(T previousValue, RecordRow element)) → T: Reduces a collection to a single value by iteratively combining each element of the collection with an existing value
inherited
followedBy(Iterable<RecordRow> other) → Iterable<RecordRow>: Creates the lazy concatenation of this iterable and other.
inherited
forEach(void action(RecordRow element)) → void: Invokes action on each element of this iterable in iteration order.
inherited
getRange(int start, int end) → Iterable<RecordRow>: Creates an Iterable that iterates over a range of elements.
inherited
head({int nRows = 5, bool asView = true}) → DataFrame: Returns a DataFrame consisting of the first nRows rows or less if the instance holds less.
indexOf(Object? element, [int start = 0]) → int: The first index of element in this list.
inherited
indexWhere(bool test(RecordRow element), [int start = 0]) → int: The first index in the list that satisfies the provided test.
inherited
insert(int index, RecordRow element) → void: Inserts element at position index in this list.
inherited
insertAll(int index, Iterable<RecordRow> iterable) → void: Inserts all objects of iterable at position index in this list.
inherited
join([String separator = ""]) → String: Converts each element to a String and concatenates the strings.
inherited
lastIndexOf(Object? element, [int? start]) → int: The last index of element in this list.
inherited
lastIndexWhere(bool test(RecordRow element), [int? start]) → int: The last index in the list that satisfies the provided test.
inherited
lastWhere(bool test(RecordRow element), {RecordRow orElse()?}) → RecordRow: The last element that satisfies the given predicate test.
inherited
map<T>(T f(RecordRow element)) → Iterable<T>: The current elements of this iterable modified by toElement.
inherited
masked(List<bool> mask, {bool asView = true}) → DataFrame: Returns a masked DataFrame.
multiIndexed(Iterable<int> indices, {bool asView = true}) → DataFrame: Returns a DataFrame composed of the rows specified through indices.
noSuchMethod(Invocation invocation) → dynamic: Invoked when a nonexistent method or property is accessed.
inherited
record<T>(int rowIndex, String colName) → T: Grab a (typed) record sitting at dataframecolName.
reduce(RecordRow combine(RecordRow previousValue, RecordRow element)) → RecordRow: Reduces a collection to a single value by iteratively combining elements of the collection using the provided function.
inherited
remove(Object? element) → bool: Removes the first occurrence of value from this list.
inherited
removeAt(int index) → RecordRow: Removes the object at position index from this list.
inherited
removeColumn(String name) → RecordCol: Remove a column from the dataframe and return it.
removeLast() → RecordRow: Removes and returns the last object in this list.
inherited
removeRange(int start, int end) → void: Removes a range of elements from the list.
inherited
removeWhere(bool test(RecordRow element)) → void: Removes all objects from this list that satisfy test.
inherited
replaceRange(int start, int end, Iterable<RecordRow> newContents) → void: Replaces a range of elements with the elements of replacements.
inherited
retainWhere(bool test(RecordRow element)) → void: Removes all objects from this list that fail to satisfy test.
inherited
rowMaps() → List<RecordRowMap>: Returns a list of {columnName: value} Map-representations for each row.
setAll(int index, Iterable<RecordRow> iterable) → void: Overwrites elements with the objects of iterable.
inherited
setRange(int start, int end, Iterable<RecordRow> iterable, [int skipCount = 0]) → void: Writes some elements of iterable into a range of this list.
inherited
shuffle([Random? random]) → void: Shuffles the elements of this list randomly.
inherited
singleWhere(bool test(RecordRow element), {RecordRow orElse()?}) → RecordRow: The single element that satisfies test.
inherited
skip(int count) → Iterable<RecordRow>: Creates an Iterable that provides all but the first count elements.
inherited
skipWhile(bool test(RecordRow element)) → Iterable<RecordRow>: Creates an Iterable that skips leading elements while test is satisfied.
inherited
slice({int start = 0, int? end}) → void: Row-slice instance in-place.
sliced({int start = 0, int? end, bool asView = true}) → DataFrame: Returns a DataFrame whose rows have been sliced with respect to start & end.
sort([int compare(RecordRow a, RecordRow b)?]) → void: Sorts this list according to the order specified by the compare function.
inherited
sortBy(String colName, {bool ascending = true, bool nullsFirst = true, Comparator<Record?>? compareRecords}) → void: In-place counterpart to sortedBy.
sortedBy(String colName, {bool ascending = true, bool nullsFirst = true, Comparator<Record?>? compareRecords}) → DataFrame: Returns a new dataframe sorted by the column colName.
sublist(int start, [int? end]) → List<RecordRow>: Returns a new list containing the elements between start and end.
inherited
take(int count) → Iterable<RecordRow>: Creates a lazy iterable of the count first elements of this iterable.
inherited
takeWhile(bool test(RecordRow element)) → Iterable<RecordRow>: Creates a lazy iterable of the leading elements satisfying test.
inherited
toCsv(String path, {bool includeHeader = true, String? nullRepresentation = null, String fieldDelimiter = ',', String textDelimiter = '"', String eolToken = '\n', Encoding encoding = utf8}) → Future<void>: Save the instance as csv to path.
toList({bool growable = true}) → List<RecordRow>: Creates a List containing the elements of this Iterable.
inherited
toSet() → Set<RecordRow>: Creates a Set containing the same elements as this iterable.
inherited
toString() → String: Returns a readable String representation of the instance including its row indices, column names & data
override
transformColumn(String name, dynamic transformElement(dynamic element)) → void: Transform the values corresponding to name as per transformElement in-place.
where(bool test(RecordRow element)) → Iterable<RecordRow>: Creates a new lazy Iterable with all elements that satisfy the predicate test.
inherited
whereType<T>() → Iterable<T>: Creates a new lazy Iterable with all elements that have type T.
inherited
withColumns(List<String> columnNames, {bool asView = true}) → DataFrame: Returns a DataFrame comprised of a subset of present columns specified by columnNames.

Operators

operator +(List<RecordRow> other) → List<RecordRow>: Returns the concatenation of this list and other.
inherited
operator ==(Object other) → bool: The equality operator.
override
operator [](int index) → RecordRow: The object at the given index in the list.
inherited
operator []=(int index, RecordRow value) → void: Sets the value at the given index in the list to value.
inherited

Static Methods

fromCsv({String? path, Stream<List<int>>? rowStream, Encoding decoding = utf8, String fieldDelimiter = ',', String textDelimiter = '"', String eolToken = '\n', bool containsHeader = true, List<String>? columnNames, List<String>? skipColumns, int? maxRows, Set<Record?> parseAsNull = const {}, bool convertNumeric = true, bool convertDates = true, String? datePattern}) → Future<DataFrame>: Build a dataframe from csv data.