more flexible type of input arguments for px functions

packages/python/plotly/plotly/express/_chart_types.py

@@ -4,7 +4,7 @@
 
 
 def scatter(
-    data_frame,
+    data_frame=None,
     x=None,
     y=None,
     color=None,
@@ -57,7 +57,7 @@ def scatter(
 
 
 def density_contour(
-    data_frame,
+    data_frame=None,
     x=None,
     y=None,
     z=None,
@@ -113,7 +113,7 @@ def density_contour(
 
 
 def density_heatmap(
-    data_frame,
+    data_frame=None,
     x=None,
     y=None,
     z=None,
@@ -167,7 +167,7 @@ def density_heatmap(
 
 
 def line(
-    data_frame,
+    data_frame=None,
     x=None,
     y=None,
     line_group=None,
@@ -212,7 +212,7 @@ def line(
 
 
 def area(
-    data_frame,
+    data_frame=None,
     x=None,
     y=None,
     line_group=None,
@@ -257,7 +257,7 @@ def area(
 
 
 def bar(
-    data_frame,
+    data_frame=None,
     x=None,
     y=None,
     color=None,
@@ -307,7 +307,7 @@ def bar(
 
 
 def histogram(
-    data_frame,
+    data_frame=None,
     x=None,
     y=None,
     color=None,
@@ -364,7 +364,7 @@ def histogram(
 
 
 def violin(
-    data_frame,
+    data_frame=None,
     x=None,
     y=None,
     color=None,
@@ -415,7 +415,7 @@ def violin(
 
 
 def box(
-    data_frame,
+    data_frame=None,
     x=None,
     y=None,
     color=None,
@@ -461,7 +461,7 @@ def box(
 
 
 def strip(
-    data_frame,
+    data_frame=None,
     x=None,
     y=None,
     color=None,
@@ -511,7 +511,7 @@ def strip(
 
 
 def scatter_3d(
-    data_frame,
+    data_frame=None,
     x=None,
     y=None,
     z=None,
@@ -562,7 +562,7 @@ def scatter_3d(
 
 
 def line_3d(
-    data_frame,
+    data_frame=None,
     x=None,
     y=None,
     z=None,
@@ -608,7 +608,7 @@ def line_3d(
 
 
 def scatter_ternary(
-    data_frame,
+    data_frame=None,
     a=None,
     b=None,
     c=None,
@@ -647,7 +647,7 @@ def scatter_ternary(
 
 
 def line_ternary(
-    data_frame,
+    data_frame=None,
     a=None,
     b=None,
     c=None,
@@ -682,7 +682,7 @@ def line_ternary(
 
 
 def scatter_polar(
-    data_frame,
+    data_frame=None,
     r=None,
     theta=None,
     color=None,
@@ -726,7 +726,7 @@ def scatter_polar(
 
 
 def line_polar(
-    data_frame,
+    data_frame=None,
     r=None,
     theta=None,
     color=None,
@@ -766,7 +766,7 @@ def line_polar(
 
 
 def bar_polar(
-    data_frame,
+    data_frame=None,
     r=None,
     theta=None,
     color=None,
@@ -804,7 +804,7 @@ def bar_polar(
 
 
 def choropleth(
-    data_frame,
+    data_frame=None,
     lat=None,
     lon=None,
     locations=None,
@@ -844,7 +844,7 @@ def choropleth(
 
 
 def scatter_geo(
-    data_frame,
+    data_frame=None,
     lat=None,
     lon=None,
     locations=None,
@@ -888,7 +888,7 @@ def scatter_geo(
 
 
 def line_geo(
-    data_frame,
+    data_frame=None,
     lat=None,
     lon=None,
     locations=None,
@@ -930,7 +930,7 @@ def line_geo(
 
 
 def scatter_mapbox(
-    data_frame,
+    data_frame=None,
     lat=None,
     lon=None,
     color=None,
@@ -966,7 +966,7 @@ def scatter_mapbox(
 
 
 def line_mapbox(
-    data_frame,
+    data_frame=None,
     lat=None,
     lon=None,
     color=None,
@@ -997,7 +997,7 @@ def line_mapbox(
 
 
 def scatter_matrix(
-    data_frame,
+    data_frame=None,
     dimensions=None,
     color=None,
     symbol=None,
@@ -1035,7 +1035,7 @@ def scatter_matrix(
 
 
 def parallel_coordinates(
-    data_frame,
+    data_frame=None,
     dimensions=None,
     color=None,
     labels={},
@@ -1059,7 +1059,7 @@ def parallel_coordinates(
 
 
 def parallel_categories(
-    data_frame,
+    data_frame=None,
     dimensions=None,
     color=None,
     labels={},

packages/python/plotly/plotly/express/_core.py

@@ -5,7 +5,7 @@
 from _plotly_utils.basevalidators import ColorscaleValidator
 from .colors import qualitative, sequential
 import math
-import pandas
+import pandas as pd
 import numpy as np
 
 from plotly.subplots import (
@@ -754,6 +754,90 @@ def apply_default_cascade(args):
         args["marginal_x"] = None
 
 
+def build_or_augment_dataframe(args, attrables, array_attrables, constructor):
+    """
+    Constructs an implicit dataframe and modifies `args` in-place.
+    `attrables` is a list of keys into `args`, all of whose corresponding
+    values are converted into columns of a dataframe.
+    Used to be support calls to plotting function that elide a dataframe
+    argument; for example `scatter(x=[1,2], y=[3,4])`.
+    """
+
+    # We start from an empty DataFrame except for the case of functions which
+    # implicitely need all dimensions: Splom, Parcats, Parcoords
+    # This could be refined when dimensions is given
+    if constructor in [go.Splom, go.Parcats, go.Parcoords]:  # we take all dimensions
+        df = args["data_frame"]
+    else:
+        df = pd.DataFrame()
+
+    # Retrieve labels (to change column names)
+    labels = args.get("labels")  # labels or None
+
+    # Valid column names
+    df_columns = (
+        args["data_frame"].columns if args.get("data_frame") is not None else None
+    )
+    group_attrs = ["symbol", "line_dash"]
+    for group_attr in group_attrs:
+        if group_attr in args:
+            attrables += [group_attr]
+
+    # Loop over possible arguments
+    for field_name in attrables:
+        argument_list = (
+            [args.get(field_name)]
+            if field_name not in array_attrables
+            else args.get(field_name)
+        )
+        if argument_list is None:  # argument not specified, continue
+            continue
+        # Argument name: field_name if the argument is a list
+        # Else we give names like ["hover_data_0, hover_data_1"] etc.
+        field_list = (
+            [field_name]
+            if field_name not in array_attrables
+            else [field_name + "_" + str(i) for i in range(len(argument_list))]
+        )
+        # argument_list and field_list ready, iterate over them
+        for i, (argument, field) in enumerate(zip(argument_list, field_list)):
+            if argument is None:
+                continue
+            elif isinstance(argument, str):  # just a column name
+                # Check validity of column name
+                try:
+                    df[argument] = args["data_frame"][argument]
+                    continue
+                except KeyError:
+                    raise ValueError(
+                        "Value of '%s' is not the name of a column in 'data_frame'. "
+                        "Expected one of %s but received: %s"
+                        % (field, str(list(df_columns)), argument)
+                    )
+            # Case of index
+            elif isinstance(argument, pd.core.indexes.range.RangeIndex):
+                col_name = argument.name if argument.name else "index"
+                col_name = labels[field] if labels and labels.get(field) else col_name
+                try:
+                    df.insert(0, col_name, argument)
+                except ValueError:  # if col named index already exists, replace
+                    df[col_name] = argument
+            # Case of numpy array or df column
+            else:
+                try:
+                    col_name = argument.name  # pandas df
+                except AttributeError:
+                    col_name = labels[field] if labels and labels.get(field) else field
+                df[col_name] = argument
+            # Update argument with column name now that column exists
+            if field_name not in array_attrables:
+                args[field_name] = col_name
+            else:
+                args[field_name][i] = col_name
+    args["data_frame"] = df
+    return args
+
+
 def infer_config(args, constructor, trace_patch):
     # Declare all supported attributes, across all plot types
     attrables = (
@@ -766,27 +850,8 @@ def infer_config(args, constructor, trace_patch):
     array_attrables = ["dimensions", "custom_data", "hover_data"]
     group_attrables = ["animation_frame", "facet_row", "facet_col", "line_group"]
 
-    # Validate that the strings provided as attribute values reference columns
-    # in the provided data_frame
-    df_columns = args["data_frame"].columns
-
-    for attr in attrables + group_attrables + ["color"]:
-        if attr in args and args[attr] is not None:
-            maybe_col_list = [args[attr]] if attr not in array_attrables else args[attr]
-            for maybe_col in maybe_col_list:
-                try:
-                    in_cols = maybe_col in df_columns
-                except TypeError:
-                    in_cols = False
-                if not in_cols:
-                    value_str = (
-                        "Element of value" if attr in array_attrables else "Value"
-                    )
-                    raise ValueError(
-                        "%s of '%s' is not the name of a column in 'data_frame'. "
-                        "Expected one of %s but received: %s"
-                        % (value_str, attr, str(list(df_columns)), str(maybe_col))
-                    )
+    all_attrables = attrables + group_attrables + ["color"]
+    build_or_augment_dataframe(args, all_attrables, array_attrables, constructor)
 
     attrs = [k for k in attrables if k in args]
     grouped_attrs = []
@@ -1095,7 +1160,7 @@ def make_figure(args, constructor, trace_patch={}, layout_patch={}):
     fig.layout.update(layout_patch)
     fig.frames = frame_list if len(frames) > 1 else []
 
-    fig._px_trendlines = pandas.DataFrame(trendline_rows)
+    fig._px_trendlines = pd.DataFrame(trendline_rows)
 
     configure_axes(args, constructor, fig, orders)
     configure_animation_controls(args, constructor, fig)