Source code for holoviews.core.pprint

HoloViews can be used to build highly-nested data-structures
containing large amounts of raw data. As a result, it is difficult to
generate a readable representation that is both informative yet

As a result, HoloViews does not attempt to build representations that
can be evaluated with eval; such representations would typically be
far too large to be practical. Instead, all HoloViews objects can be
represented as tree structures, showing how to access and index into
your data.

In addition, there are several different ways of

import sys, re
import param
# IPython not required to import ParamPager
from param.ipython import ParamPager
from holoviews.core.util import group_sanitizer, label_sanitizer

class ParamFilter(param.ParameterizedFunction):
    Given a parameterized object, return a proxy parameterized object
    holding only the parameters that match some filter criterion.

    A filter is supplied with the parameter name and the parameter
    object and must return a boolean. A regular expression filter has
    been supplied and may be used to search for parameters mentioning
    'bounds' as follows:

    filtered = ParamFilter(obj, ParamFilter.regexp_filter('bounds'))

    This may be used to filter documentation generated by param.

    def __call__(self, obj, filter_fn=None):
        if filter_fn is None:
            return obj

        name = obj.__name__ if isinstance(obj,type) else obj.__class__.__name__
        class_proxy = type(name, (param.Parameterized,),
                      {k:v for k,v in obj.params().items() if filter_fn(k,v)})

        if isinstance(obj,type):
            return class_proxy
            instance_params = obj.get_param_values()
            obj_proxy = class_proxy()
            filtered = {k:v for k,v in instance_params
                        if (k in obj_proxy.params())
                            and not obj_proxy.params(k).constant}
            return obj_proxy

    def regexp_filter(self_or_cls, pattern):
        Builds a parameter filter using the supplied pattern (may be a
        general Python regular expression)
        def inner_filter(name, p):
            name_match =,name)
            if name_match is not None:
                return True
            doc_match =,p.doc)
            if doc_match is not None:
                return True
            return False
        return inner_filter

[docs]class InfoPrinter(object): """ Class for printing other information related to an object that is of use to the user. """ headings = ['\x1b[1;35m%s\x1b[0m', '\x1b[1;32m%s\x1b[0m'] ansi_escape = re.compile(r'\x1b[^m]*m') ppager = ParamPager() store = None elements = []
[docs] @classmethod def get_parameter_info(cls, obj, ansi=False, show_values=True, pattern=None, max_col_len=40): """ Get parameter information from the supplied class or object. """ if cls.ppager is None: return '' if pattern is not None: obj = ParamFilter(obj, ParamFilter.regexp_filter(pattern)) if len(obj.params()) <=1: return None param_info = cls.ppager.get_param_info(obj) param_list = cls.ppager.param_docstrings(param_info) if not show_values: retval = cls.ansi_escape.sub('', param_list) if not ansi else param_list return cls.highlight(pattern, retval) else: info = cls.ppager(obj) if ansi is False: info = cls.ansi_escape.sub('', info) return cls.highlight(pattern, info)
[docs] @classmethod def heading(cls, heading_text, char='=', level=0, ansi=False): """ Turn the supplied heading text into a suitable heading with optional underline and color. """ heading_color = cls.headings[level] if ansi else '%s' if char is None: return heading_color % '%s\n' % heading_text else: heading_ul = char*len(heading_text) return heading_color % '%s\n%s\n%s' % (heading_ul, heading_text, heading_ul)
@classmethod def highlight(cls, pattern, string): if pattern is None: return string return re.sub(pattern, '\033[43;1;30m\g<0>\x1b[0m', string, flags=re.IGNORECASE)
[docs] @classmethod def info(cls, obj, ansi=False, backend='matplotlib', visualization=True, pattern=None, elements=[]): """ Show information about an object in the given category. ANSI color codes may be enabled or disabled. """ cls.elements = elements ansi_escape = re.compile(r'\x1b[^m]*m') isclass = isinstance(obj, type) name = obj.__name__ if isclass else obj.__class__.__name__ backend_registry =, {}) plot_class = backend_registry.get(obj if isclass else type(obj), None) # Special case to handle PlotSelectors if hasattr(plot_class, 'plot_classes'): plot_class = list(plot_class.plot_classes.values())[0] if visualization is False or plot_class is None: if pattern is not None: obj = ParamFilter(obj, ParamFilter.regexp_filter(pattern)) if len(obj.params()) <=1: return ('No %r parameters found matching specified pattern %r' % (name, pattern)) info = param.ipython.ParamPager()(obj) if ansi is False: info = ansi_escape.sub('', info) return cls.highlight(pattern, info) heading = name if isclass else '{name}: {group} {label}'.format(name=name,, label=obj.label) prefix = heading lines = [prefix, cls.object_info(obj, name, backend=backend, ansi=ansi)] if not isclass: lines += ['', cls.target_info(obj, ansi=ansi)] if plot_class is not None: lines += ['', cls.options_info(plot_class, ansi, pattern=pattern)] return "\n".join(lines)
@classmethod def get_target(cls, obj): objtype=obj.__class__.__name__ group = group_sanitizer( label = ('.' + label_sanitizer(obj.label) if obj.label else '') target = '{objtype}.{group}{label}'.format(objtype=objtype, group=group, label=label) return (None, target) if hasattr(obj, 'values') else (target, None) @classmethod def target_info(cls, obj, ansi=False): if isinstance(obj, type): return '' targets = obj.traverse(cls.get_target) elements, containers = zip(*targets) element_set = set(el for el in elements if el is not None) container_set = set(c for c in containers if c is not None) element_info = None if len(element_set) == 1: element_info = 'Element: %s' % list(element_set)[0] elif len(element_set) > 1: element_info = 'Elements:\n %s' % '\n '.join(sorted(element_set)) container_info = None if len(container_set) == 1: container_info = 'Container: %s' % list(container_set)[0] elif len(container_set) > 1: container_info = 'Containers:\n %s' % '\n '.join(sorted(container_set)) heading = cls.heading('Target Specifications', ansi=ansi, char="-") target_header = '\nTargets in this object available for customization:\n' if element_info and container_info: target_info = '%s\n\n%s' % (element_info, container_info) else: target_info = element_info if element_info else container_info target_footer = ("\nTo see the options info for one of these target specifications," "\nwhich are of the form {type}[.{group}[.{label}]], do{type}).") return '\n'.join([heading, target_header, target_info, target_footer]) @classmethod def object_info(cls, obj, name, backend, ansi=False): element = not getattr(obj, '_deep_indexable', False) element_url ='{backend}/{obj}.html' container_url ='{backend}/{obj}.html' url = element_url if element else container_url link = url.format(obj=name, backend=backend) link = None if element and (name not in cls.elements) else link msg = ("\nOnline example: {link}" if link else '' + "\nHelp for the data object:{obj})" + " or<{lower}_instance>)") return '\n'.join([msg.format(obj=name, lower=name.lower(), link=link)]) @classmethod def options_info(cls, plot_class, ansi=False, pattern=None): if plot_class.style_opts: backend_name = plot_class.backend style_info = ("\n(Consult %s's documentation for more information.)" % backend_name) style_keywords = '\t%s' % ', '.join(plot_class.style_opts) style_msg = '%s\n%s' % (style_keywords, style_info) else: style_msg = '\t<No style options available>' param_info = cls.get_parameter_info(plot_class, ansi=ansi, pattern=pattern) lines = [ cls.heading('Style Options', ansi=ansi, char="-"), '', style_msg, '', cls.heading('Plot Options', ansi=ansi, char="-"), ''] if param_info is not None: lines += ["The plot options are the parameters of the plotting class:\n", param_info] elif pattern is not None: lines+= ['No %r parameters found matching specified pattern %r.' % (plot_class.__name__, pattern)] else: lines+= ['No %r parameters found.' % plot_class.__name__] return '\n'.join(lines)
[docs]class PrettyPrinter(object): """ The PrettyPrinter used to print all HoloView objects via the pprint classmethod. """ tab = ' ' type_formatter= ':{type}' @classmethod def pprint(cls, node): reprval = cls.serialize(cls.recurse(node)) if sys.version_info.major == 2: return str(reprval.encode("utf8")) else: return str(reprval) @classmethod def serialize(cls, lines): accumulator = [] for level, line in lines: accumulator.append((level * + line) return "\n".join(accumulator) @classmethod def shift(cls, lines, shift=0): return [(lvl+shift, line) for (lvl, line) in lines] @classmethod def padding(cls, items): return max(len(p) for p in items) if len(items) > 1 else len(items[0])
[docs] @classmethod def component_type(cls, node): "Return the dotted information" if node is None: return '' return cls.type_formatter.format(type=str(type(node).__name__))
[docs] @classmethod def recurse(cls, node, attrpath=None, attrpaths=[], siblings=[], level=0, value_dims=True): """ Recursive function that builds up an ASCII tree given an AttrTree node. """ level, lines = cls.node_info(node, attrpath, attrpaths, siblings, level, value_dims) attrpaths = ['.'.join(k) for k in node.keys()] if hasattr(node, 'children') else [] siblings = [node.get(child) for child in attrpaths] for attrpath in attrpaths: lines += cls.recurse(node.get(attrpath), attrpath, attrpaths=attrpaths, siblings=siblings, level=level+1, value_dims=value_dims) return lines
[docs] @classmethod def node_info(cls, node, attrpath, attrpaths, siblings, level, value_dims): """ Given a node, return relevant information. """ if hasattr(node, 'children'): (lvl, lines) = (level, [(level, cls.component_type(node))]) elif hasattr(node, 'main'): (lvl, lines) = cls.adjointlayout_info(node, siblings, level, value_dims) elif getattr(node, '_deep_indexable', False): (lvl, lines) = cls.ndmapping_info(node, siblings, level, value_dims) elif hasattr(node, 'unit_format'): (lvl, lines) = level, [(level, repr(node))] else: (lvl, lines) = cls.element_info(node, siblings, level, value_dims) # The attribute indexing path acts as a prefix (if applicable) if attrpath is not None: padding = cls.padding(attrpaths) (fst_lvl, fst_line) = lines[0] lines[0] = (fst_lvl, '.'+attrpath.ljust(padding) +' ' + fst_line) return (lvl, lines)
[docs] @classmethod def element_info(cls, node, siblings, level, value_dims): """ Return the information summary for an Element. This consists of the dotted name followed by an value dimension names. """ info = cls.component_type(node) if siblings: padding = cls.padding([cls.component_type(el) for el in siblings]) info.ljust(padding) if len(node.kdims) >= 1: info += + '[%s]' % ','.join( for d in node.kdims) if value_dims and len(node.vdims) >= 1: info += + '(%s)' % ','.join( for d in node.vdims) return level, [(level, info)]
@classmethod def adjointlayout_info(cls, node, siblings, level, value_dims): first_line = cls.component_type(node) lines = [(level, first_line)] additional_lines = [] for component in list( additional_lines += cls.recurse(component, level=level) lines += cls.shift(additional_lines, 1) return level, lines @classmethod def ndmapping_info(cls, node, siblings, level, value_dims): key_dim_info = '[%s]' % ','.join( for d in node.kdims) first_line = cls.component_type(node) + + key_dim_info lines = [(level, first_line)] additional_lines = [] if len( == 0: return level, lines # .last has different semantics for GridSpace last = list([-1] if hasattr(last, 'children'): additional_lines = cls.recurse(last, level=level) # NdOverlays, GridSpace, Ndlayouts elif last is not None and getattr(last, '_deep_indexable'): level, additional_lines = cls.ndmapping_info(last, [], level, value_dims) else: _, additional_lines = cls.element_info(last, siblings, level, value_dims) lines += cls.shift(additional_lines, 1) return level, lines
__all__ = ['PrettyPrinter', 'InfoPrinter']