bokeh.models.sources¶
-
class
AjaxDataSource(*args, **kw)[source]¶ Bases:
bokeh.models.sources.RemoteSource-
if_modified¶ property type:
BoolWhether to include an
If-Modified-Sinceheader in AJAX requests to the server. If this header is supported by the server, then only new data since the last request will be returned.
-
-
class
ColumnDataSource(*args, **kw)[source]¶ Bases:
bokeh.models.sources.ColumnarDataSourceMaps names of columns to sequences or arrays.
If the ColumnDataSource initializer is called with a single argument that is a dict or pandas.DataFrame, that argument is used as the value for the “data” attribute. For example:
ColumnDataSource(mydict) # same as ColumnDataSource(data=mydict) ColumnDataSource(df) # same as ColumnDataSource(data=df)
Note
There is an implicit assumption that all the columns in a a given ColumnDataSource have the same length.
-
data¶ property type:
ColumnData(String,Seq(Any) )Mapping of column names to sequences of data. The data can be, e.g, Python lists or tuples, NumPy arrays, etc.
-
add(data, name=None)[source]¶ Appends a new column of data to the data source.
Parameters: - data (seq) – new data to add
- name (str, optional) – column name to use. If not supplied, generate a name of the form “Series ####”
Returns: the column name used
Return type:
-
classmethod
from_df(data)[source]¶ Create a
dictof columns from a Pandas DataFrame, suitable for creating a ColumnDataSource.Parameters: data (DataFrame) – data to convert Returns: dict[str, np.array]
-
patch(patches, setter=None)[source]¶ Efficiently update data source columns at specific locations
If it is only necessary to update a small subset of data in a ColumnDataSource, this method can be used to efficiently update only the subset, instead of requiring the entire data set to be sent.
This method should be passed a dictionary that maps column names to lists of tuples that describe a patch change to apply. To replace individual items in columns entirely, the tuples should be of the form:
(index, new_value) # replace a single column value # or (slice, new_values) # replace several column values
Values at an index or slice will be replaced with the corresponding new values.
In the case of columns whose values are other arrays or lists, (e.g. image or patches glyphs), it is also possible to patch “subregions”. In this case the first item of the tuple should be a whose first element is the index of the array item in the CDS patch, and whose subsequent elements are integer indices or slices into the array item:
# replace the entire 10th column of the 2nd array: +----------------- index of item in column data source | | +--------- row subindex into array item | | | | +- column subindex into array item V V V ([2, slice(None), 10], new_values)
Imagining a list of 2d NumPy arrays, the patch above is roughly equivalent to:
data = [arr1, arr2, ...] # list of 2d arrays data[2][:, 10] = new_data
There are some limitations to the kinds of slices and data that can be accepted.
- Negative
start,stop, orstepvalues for slices will result in aValueError. - In a slice,
start > stopwill result in aValueError - When patching 1d or 2d subitems, the subitems must be NumPy arrays.
- New values must be supplied as a flattened one-dimensional array of the appropriate size.
Parameters: patches (dict[str, list[tuple]]) – lists of patches for each column Returns: None Raises: ValueErrorExample:
The following example shows how to patch entire column elements. In this case,
source = ColumnDataSource(data=dict(foo=[10, 20, 30], bar=[100, 200, 300])) patches = { 'foo' : [ (slice(2), [11, 12]) ], 'bar' : [ (0, 101), (2, 301) ], } source.patch(patches)
After this operation, the value of the
source.datawill be:dict(foo=[11, 22, 30], bar=[101, 200, 301])
For a more comprehensive complete example, see examples/howto/patch_app.py.
- Negative
-
remove(name)[source]¶ Remove a column of data.
Parameters: name (str) – name of the column to remove Returns: None Note
If the column name does not exist, a warning is issued.
-
stream(new_data, rollover=None, setter=None)[source]¶ Efficiently update data source columns with new append-only data.
In cases where it is necessary to update data columns in, this method can efficiently send only the new data, instead of requiring the entire data set to be re-sent.
Parameters: - new_data (dict[str, seq]) –
a mapping of column names to sequences of new data to append to each column.
All columns of the data source must be present in
new_data, with identical-length append data. - rollover (int, optional) – A maximum column size, above which data from the start of the column begins to be discarded. If None, then columns will continue to grow unbounded (default: None)
Returns: None
Raises: ValueErrorExample:
source = ColumnDataSource(data=dict(foo=[], bar=[])) # has new, identical-length updates for all columns in source new_data = { 'foo' : [10, 20], 'bar' : [100, 200], } source.stream(new_data)
- new_data (dict[str, seq]) –
-
-
class
ColumnarDataSource(**kwargs)[source]¶ Bases:
bokeh.models.sources.DataSourceA base class for data source types, which can be mapped onto a columnar format.
Note
This is an abstract base class used to help organize the hierarchy of Bokeh model types. It is not useful to instantiate on its own.
-
class
DataSource(**kwargs)[source]¶ Bases:
bokeh.model.ModelA base class for data source types.
Note
This is an abstract base class used to help organize the hierarchy of Bokeh model types. It is not useful to instantiate on its own.
-
callback¶ property type:
Instance(Callback)A callback to run in the browser whenever the selection is changed.
-
selected¶ property type:
Dict(String,Dict(String,Any) )A dict to indicate selected indices on different dimensions on this DataSource. Keys are:
# selection information for line and patch glyphs '0d' : { # the glyph that was selected 'glyph': None # array with the [smallest] index of the segment of the line that was hit 'indices': [] } # selection for most (point-like) glyphs, except lines and patches '1d': { # indices of the points included in the selection indices: [] } # selection information for multiline and patches glyphs '2d': { # mapping of indices of the multiglyph to array of glyph indices that were hit # e.g. {3: [5, 6], 4: [5]} indices: {} }
-
-
class
RemoteSource(*args, **kw)[source]¶ Bases:
bokeh.models.sources.ColumnDataSourceNote
This is an abstract base class used to help organize the hierarchy of Bokeh model types. It is not useful to instantiate on its own.