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pl_pca_variance_ratio

Plot PCA variance ratios to visualize explained variance in single-cell RNA sequencing data, aiding dimensionality reduction and analysis interpretation. Supports customizable plotting parameters.

Instructions

Plot the PCA variance ratio to visualize explained variance.

Input Schema

TableJSON Schema
NameRequiredDescriptionDefault
color_mapNoColor map to use for continuous variables.
figsizeNoFigure size. Format is (width, height).
legend_fontoutlineNoLine width of the legend font outline in pt.
legend_fontsizeNoNumeric size in pt or string describing the size.
legend_fontweightNoLegend font weight. A numeric value in range 0-1000 or a string.bold
legend_locNoLocation of legend, either 'on data', 'right margin' or a valid keyword for the loc parameter.right margin
logNoPlot on logarithmic scale.
n_pcsNoNumber of PCs to show.
paletteNoColors to use for plotting categorical annotation groups.
vcenterNoThe value representing the center of the color scale.
vmaxNoThe value representing the upper limit of the color scale.
vminNoThe value representing the lower limit of the color scale.

Implementation Reference

  • The main handler function that executes the tool logic for all pl tools, including pl_pca_variance_ratio, by looking up the scanpy function in pl_func and calling it with prepared arguments from the input schema.
    def run_pl_func(ads, func, arguments): """ Execute a Scanpy plotting function with the given arguments. Parameters ---------- adata : AnnData Annotated data matrix. func : str Name of the plotting function to execute. arguments : dict Arguments to pass to the plotting function. Returns ------- The result of the plotting function. """ adata = ads.adata_dic[ads.active] if func not in pl_func: raise ValueError(f"Unsupported function: {func}") run_func = pl_func[func] parameters = inspect.signature(run_func).parameters kwargs = {k: arguments.get(k) for k in parameters if k in arguments} if "title" not in parameters: kwargs.pop("title", False) kwargs.pop("return_fig", True) kwargs["show"] = False kwargs["save"] = ".png" try: fig = run_func(adata, **kwargs) fig_path = set_fig_path(func, **kwargs) add_op_log(adata, run_func, kwargs) return fig_path except Exception as e: raise e return fig_path
  • Pydantic model defining the input schema for the pl_pca_variance_ratio tool, with parameters n_pcs and log.
    class PCAVarianceRatioModel(BaseVisualizationModel): """Input schema for the pca_variance_ratio plotting tool.""" n_pcs: int = Field( default=30, description="Number of PCs to show.", gt=0 ) log: bool = Field( default=False, description="Plot on logarithmic scale." ) @field_validator('n_pcs') def validate_n_pcs(cls, v: int) -> int: """Validate n_pcs is positive""" if v <= 0: raise ValueError("n_pcs must be a positive integer") return v
  • Definition and registration of the MCP Tool instance for pl_pca_variance_ratio, including name, description, and schema reference.
    pl_pca_variance_ratio = types.Tool( name="pl_pca_variance_ratio", description="Plot the PCA variance ratio to visualize explained variance.", inputSchema=PCAVarianceRatioModel.model_json_schema(), )
  • Mapping dictionary pl_func that associates the tool name 'pl_pca_variance_ratio' with the core scanpy handler function sc.pl.pca_variance_ratio, used by run_pl_func.
    pl_func = { "pl_pca": sc.pl.pca, "pl_embedding": sc.pl.embedding, # Add the new embedding function "diffmap": sc.pl.diffmap, "pl_violin": sc.pl.violin, "pl_stacked_violin": sc.pl.stacked_violin, "pl_heatmap": sc.pl.heatmap, "pl_dotplot": sc.pl.dotplot, "pl_matrixplot": sc.pl.matrixplot, "pl_tracksplot": sc.pl.tracksplot, "pl_scatter": sc.pl.scatter, "embedding_density": sc.pl.embedding_density, "rank_genes_groups": sc.pl.rank_genes_groups, "pl_rank_genes_groups_dotplot": sc.pl.rank_genes_groups_dotplot, # Add function mapping "pl_clustermap": sc.pl.clustermap, "pl_highly_variable_genes": sc.pl.highly_variable_genes, "pl_pca_variance_ratio": sc.pl.pca_variance_ratio, }
  • Tools dictionary pl_tools that registers the pl_pca_variance_ratio Tool instance for use in the MCP server.
    pl_tools = { "pl_pca": pl_pca_tool, "pl_embedding": pl_embedding, # Add the new embedding tool # "diffmap": diffmap, "pl_violin": pl_violin, "pl_stacked_violin": pl_stacked_violin, "pl_heatmap": pl_heatmap, "pl_dotplot": pl_dotplot, "pl_matrixplot": pl_matrixplot, "pl_tracksplot": pl_tracksplot, "pl_scatter": pl_scatter, # "embedding_density": embedding_density, # "spatial": spatial, # "rank_genes_groups": rank_genes_groups, "pl_rank_genes_groups_dotplot": pl_rank_genes_groups_dotplot, # Add tool mapping # "pl_clustermap": pl_clustermap, "pl_highly_variable_genes": pl_highly_variable_genes, "pl_pca_variance_ratio": pl_pca_variance_ratio, }

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