scanpy.pl.stacked_violin
- scanpy.pl.stacked_violin(adata, var_names, groupby, log=False, use_raw=None, num_categories=7, title=None, colorbar_title='Median expression\\nin group', figsize=None, dendrogram=False, gene_symbols=None, var_group_positions=None, var_group_labels=None, standard_scale=None, var_group_rotation=None, layer=None, stripplot=False, jitter=False, size=1, scale='width', yticklabels=False, order=None, swap_axes=False, show=None, save=None, return_fig=False, row_palette=None, cmap='Blues', ax=None, vmin=None, vmax=None, vcenter=None, norm=None, **kwds)
Stacked violin plots.
Makes a compact image composed of individual violin plots (from
violinplot()) stacked on top of each other. Useful to visualize gene expression per cluster.Wraps
seaborn.violinplot()forAnnData.This function provides a convenient interface to the
StackedViolinclass. If you need more flexibility, you should useStackedViolindirectly.- Parameters:
- adata :
AnnData Annotated data matrix.
- var_names :
Union[str,Sequence[str],Mapping[str,Union[str,Sequence[str]]]] var_namesshould be a valid subset ofadata.var_names. Ifvar_namesis a mapping, then the key is used as label to group the values (seevar_group_labels). The mapping values should be sequences of validadata.var_names. In this case either coloring or ‘brackets’ are used for the grouping of var names depending on the plot. Whenvar_namesis a mapping, then thevar_group_labelsandvar_group_positionsare set.- groupby :
Union[str,Sequence[str]] The key of the observation grouping to consider.
- use_raw :
Optional[bool] (default:None) Use
rawattribute ofadataif present.- log :
bool(default:False) Plot on logarithmic axis.
- num_categories :
int(default:7) Only used if groupby observation is not categorical. This value determines the number of groups into which the groupby observation should be subdivided.
- categories_order
Order in which to show the categories. Note: add_dendrogram or add_totals can change the categories order.
- figsize :
Optional[Tuple[float,float]] (default:None) Figure size when
multi_panel=True. Otherwise thercParam['figure.figsize]value is used. Format is (width, height)- dendrogram :
Union[bool,str] (default:False) If True or a valid dendrogram key, a dendrogram based on the hierarchical clustering between the
groupbycategories is added. The dendrogram information is computed usingscanpy.tl.dendrogram(). Iftl.dendrogramhas not been called previously the function is called with default parameters.- gene_symbols :
Optional[str] (default:None) Column name in
.varDataFrame that stores gene symbols. By defaultvar_namesrefer to the index column of the.varDataFrame. Setting this option allows alternative names to be used.- var_group_positions :
Optional[Sequence[Tuple[int,int]]] (default:None) Use this parameter to highlight groups of
var_names. This will draw a ‘bracket’ or a color block between the given start and end positions. If the parametervar_group_labelsis set, the corresponding labels are added on top/left. E.g.var_group_positions=[(4,10)]will add a bracket between the fourthvar_nameand the tenthvar_name. By giving more positions, more brackets/color blocks are drawn.- var_group_labels :
Optional[Sequence[str]] (default:None) Labels for each of the
var_group_positionsthat want to be highlighted.- var_group_rotation :
Optional[float] (default:None) Label rotation degrees. By default, labels larger than 4 characters are rotated 90 degrees.
- layer :
Optional[str] (default:None) Name of the AnnData object layer that wants to be plotted. By default adata.raw.X is plotted. If
use_raw=Falseis set, thenadata.Xis plotted. Iflayeris set to a valid layer name, then the layer is plotted.layertakes precedence overuse_raw.- title :
Optional[str] (default:None) Title for the figure
- colorbar_title :
Optional[str] (default:'Median expression\\nin group') Title for the color bar. New line character (n) can be used.
- cmap :
Optional[str] (default:'Blues') String denoting matplotlib color map.
- standard_scale :
Optional[Literal['var','obs']] (default:None) Whether or not to standardize the given dimension between 0 and 1, meaning for each variable or group, subtract the minimum and divide each by its maximum.
- swap_axes :
bool(default:False) By default, the x axis contains
var_names(e.g. genes) and the y axis thegroupbycategories. By settingswap_axesthen x are thegroupbycategories and y thevar_names.- return_fig :
Optional[bool] (default:False) Returns
DotPlotobject. Useful for fine-tuning the plot. Takes precedence overshow=False.- stripplot :
bool(default:False) Add a stripplot on top of the violin plot. See
stripplot().- jitter :
Union[float,bool] (default:False) Add jitter to the stripplot (only when stripplot is True) See
stripplot().- size :
int(default:1) Size of the jitter points.
- order :
Optional[Sequence[str]] (default:None) Order in which to show the categories. Note: if
dendrogram=Truethe categories order will be given by the dendrogram andorderwill be ignored.- scale :
Literal['area','count','width'] (default:'width') The method used to scale the width of each violin. If ‘width’ (the default), each violin will have the same width. If ‘area’, each violin will have the same area. If ‘count’, a violin’s width corresponds to the number of observations.
- yticklabels :
Optional[bool] (default:False) Set to true to view the y tick labels.
- row_palette :
Optional[str] (default:None) Be default, median values are mapped to the violin color using a color map (see
cmapargument). Alternatively, a ‘row_palette` can be given to color each violin plot row using a different colors. The value should be a valid seaborn or matplotlib palette name (seecolor_palette()). Alternatively, a single color name or hex value can be passed, e.g.'red'or'#cc33ff'.- show :
Optional[bool] (default:None) Show the plot, do not return axis.
- save :
Union[str,bool,None] (default:None) If
Trueor astr, save the figure. A string is appended to the default filename. Infer the filetype if ending on {'.pdf','.png','.svg'}.- ax :
Optional[_AxesSubplot] (default:None) A matplotlib axes object. Only works if plotting a single component.
- vmin :
Optional[float] (default:None) The value representing the lower limit of the color scale. Values smaller than vmin are plotted with the same color as vmin.
- vmax :
Optional[float] (default:None) The value representing the upper limit of the color scale. Values larger than vmax are plotted with the same color as vmax.
- vcenter :
Optional[float] (default:None) The value representing the center of the color scale. Useful for diverging colormaps.
- norm :
Optional[Normalize] (default:None) Custom color normalization object from matplotlib. See
https://matplotlib.org/stable/tutorials/colors/colormapnorms.htmlfor details.- kwds
Are passed to
violinplot().
- adata :
- Return type:
- Returns:
: If
return_figisTrue, returns aStackedViolinobject, else ifshowis false, return axes dict
See also
StackedViolinThe StackedViolin class can be used to to control several visual parameters not available in this function.
rank_genes_groups_stacked_violin()using the
rank_genes_groups()function.
Examples
Visualization of violin plots of a few genes grouped by the category ‘bulk_labels’:
>>> import scanpy as sc >>> adata = sc.datasets.pbmc68k_reduced() >>> markers = ['C1QA', 'PSAP', 'CD79A', 'CD79B', 'CST3', 'LYZ'] >>> sc.pl.stacked_violin(adata, markers, groupby='bulk_labels', dendrogram=True)
Same visualization but passing var_names as dict, which adds a grouping of the genes on top of the image:
>>> markers = {'T-cell': 'CD3D', 'B-cell': 'CD79A', 'myeloid': 'CST3'} >>> sc.pl.stacked_violin(adata, markers, groupby='bulk_labels', dendrogram=True)
Get StackedViolin object for fine tuning
>>> vp = sc.pl.stacked_violin(adata, markers, 'bulk_labels', return_fig=True) >>> vp.add_totals().style(ylim=(0,5)).show()
The axes used can be obtained using the get_axes() method:
>>> axes_dict = vp.get_axes()