376 lines
15 KiB
Python
376 lines
15 KiB
Python
import numpy as np
|
|
import pandas as pd
|
|
import plotly.graph_objects as go
|
|
import math
|
|
|
|
from typing import List, Union
|
|
|
|
|
|
def visualize_hierarchical_documents(
|
|
topic_model,
|
|
docs: List[str],
|
|
hierarchical_topics: pd.DataFrame,
|
|
topics: List[int] = None,
|
|
embeddings: np.ndarray = None,
|
|
reduced_embeddings: np.ndarray = None,
|
|
sample: Union[float, int] = None,
|
|
hide_annotations: bool = False,
|
|
hide_document_hover: bool = True,
|
|
nr_levels: int = 10,
|
|
level_scale: str = "linear",
|
|
custom_labels: Union[bool, str] = False,
|
|
title: str = "<b>Hierarchical Documents and Topics</b>",
|
|
width: int = 1200,
|
|
height: int = 750,
|
|
) -> go.Figure:
|
|
"""Visualize documents and their topics in 2D at different levels of hierarchy.
|
|
|
|
Arguments:
|
|
topic_model: A fitted BERTopic instance.
|
|
docs: The documents you used when calling either `fit` or `fit_transform`
|
|
hierarchical_topics: A dataframe that contains a hierarchy of topics
|
|
represented by their parents and their children
|
|
topics: A selection of topics to visualize.
|
|
Not to be confused with the topics that you get from `.fit_transform`.
|
|
For example, if you want to visualize only topics 1 through 5:
|
|
`topics = [1, 2, 3, 4, 5]`.
|
|
embeddings: The embeddings of all documents in `docs`.
|
|
reduced_embeddings: The 2D reduced embeddings of all documents in `docs`.
|
|
sample: The percentage of documents in each topic that you would like to keep.
|
|
Value can be between 0 and 1. Setting this value to, for example,
|
|
0.1 (10% of documents in each topic) makes it easier to visualize
|
|
millions of documents as a subset is chosen.
|
|
hide_annotations: Hide the names of the traces on top of each cluster.
|
|
hide_document_hover: Hide the content of the documents when hovering over
|
|
specific points. Helps to speed up generation of visualizations.
|
|
nr_levels: The number of levels to be visualized in the hierarchy. First, the distances
|
|
in `hierarchical_topics.Distance` are split in `nr_levels` lists of distances.
|
|
Then, for each list of distances, the merged topics are selected that have a
|
|
distance less or equal to the maximum distance of the selected list of distances.
|
|
NOTE: To get all possible merged steps, make sure that `nr_levels` is equal to
|
|
the length of `hierarchical_topics`.
|
|
level_scale: Whether to apply a linear or logarithmic (log) scale levels of the distance
|
|
vector. Linear scaling will perform an equal number of merges at each level
|
|
while logarithmic scaling will perform more mergers in earlier levels to
|
|
provide more resolution at higher levels (this can be used for when the number
|
|
of topics is large).
|
|
custom_labels: If bool, whether to use custom topic labels that were defined using
|
|
`topic_model.set_topic_labels`.
|
|
If `str`, it uses labels from other aspects, e.g., "Aspect1".
|
|
NOTE: Custom labels are only generated for the original
|
|
un-merged topics.
|
|
title: Title of the plot.
|
|
width: The width of the figure.
|
|
height: The height of the figure.
|
|
|
|
Examples:
|
|
To visualize the topics simply run:
|
|
|
|
```python
|
|
topic_model.visualize_hierarchical_documents(docs, hierarchical_topics)
|
|
```
|
|
|
|
Do note that this re-calculates the embeddings and reduces them to 2D.
|
|
The advised and preferred pipeline for using this function is as follows:
|
|
|
|
```python
|
|
from sklearn.datasets import fetch_20newsgroups
|
|
from sentence_transformers import SentenceTransformer
|
|
from bertopic import BERTopic
|
|
from umap import UMAP
|
|
|
|
# Prepare embeddings
|
|
docs = fetch_20newsgroups(subset='all', remove=('headers', 'footers', 'quotes'))['data']
|
|
sentence_model = SentenceTransformer("all-MiniLM-L6-v2")
|
|
embeddings = sentence_model.encode(docs, show_progress_bar=False)
|
|
|
|
# Train BERTopic and extract hierarchical topics
|
|
topic_model = BERTopic().fit(docs, embeddings)
|
|
hierarchical_topics = topic_model.hierarchical_topics(docs)
|
|
|
|
# Reduce dimensionality of embeddings, this step is optional
|
|
# reduced_embeddings = UMAP(n_neighbors=10, n_components=2, min_dist=0.0, metric='cosine').fit_transform(embeddings)
|
|
|
|
# Run the visualization with the original embeddings
|
|
topic_model.visualize_hierarchical_documents(docs, hierarchical_topics, embeddings=embeddings)
|
|
|
|
# Or, if you have reduced the original embeddings already:
|
|
topic_model.visualize_hierarchical_documents(docs, hierarchical_topics, reduced_embeddings=reduced_embeddings)
|
|
```
|
|
|
|
Or if you want to save the resulting figure:
|
|
|
|
```python
|
|
fig = topic_model.visualize_hierarchical_documents(docs, hierarchical_topics, reduced_embeddings=reduced_embeddings)
|
|
fig.write_html("path/to/file.html")
|
|
```
|
|
|
|
Note:
|
|
This visualization was inspired by the scatter plot representation of Doc2Map:
|
|
https://github.com/louisgeisler/Doc2Map
|
|
|
|
<iframe src="../../getting_started/visualization/hierarchical_documents.html"
|
|
style="width:1000px; height: 770px; border: 0px;""></iframe>
|
|
"""
|
|
topic_per_doc = topic_model.topics_
|
|
|
|
# Sample the data to optimize for visualization and dimensionality reduction
|
|
if sample is None or sample > 1:
|
|
sample = 1
|
|
|
|
indices = []
|
|
for topic in set(topic_per_doc):
|
|
s = np.where(np.array(topic_per_doc) == topic)[0]
|
|
size = len(s) if len(s) < 100 else int(len(s) * sample)
|
|
indices.extend(np.random.choice(s, size=size, replace=False))
|
|
indices = np.array(indices)
|
|
|
|
df = pd.DataFrame({"topic": np.array(topic_per_doc)[indices]})
|
|
df["doc"] = [docs[index] for index in indices]
|
|
df["topic"] = [topic_per_doc[index] for index in indices]
|
|
|
|
# Extract embeddings if not already done
|
|
if sample is None:
|
|
if embeddings is None and reduced_embeddings is None:
|
|
embeddings_to_reduce = topic_model._extract_embeddings(df.doc.to_list(), method="document")
|
|
else:
|
|
embeddings_to_reduce = embeddings
|
|
else:
|
|
if embeddings is not None:
|
|
embeddings_to_reduce = embeddings[indices]
|
|
elif embeddings is None and reduced_embeddings is None:
|
|
embeddings_to_reduce = topic_model._extract_embeddings(df.doc.to_list(), method="document")
|
|
|
|
# Reduce input embeddings
|
|
if reduced_embeddings is None:
|
|
try:
|
|
from umap import UMAP
|
|
|
|
umap_model = UMAP(n_neighbors=10, n_components=2, min_dist=0.0, metric="cosine").fit(embeddings_to_reduce)
|
|
embeddings_2d = umap_model.embedding_
|
|
except (ImportError, ModuleNotFoundError):
|
|
raise ModuleNotFoundError(
|
|
"UMAP is required if the embeddings are not yet reduced in dimensionality. Please install it using `pip install umap-learn`."
|
|
)
|
|
elif sample is not None and reduced_embeddings is not None:
|
|
embeddings_2d = reduced_embeddings[indices]
|
|
elif sample is None and reduced_embeddings is not None:
|
|
embeddings_2d = reduced_embeddings
|
|
|
|
# Combine data
|
|
df["x"] = embeddings_2d[:, 0]
|
|
df["y"] = embeddings_2d[:, 1]
|
|
|
|
# Create topic list for each level, levels are created by calculating the distance
|
|
distances = hierarchical_topics.Distance.to_list()
|
|
if level_scale == "log" or level_scale == "logarithmic":
|
|
log_indices = (
|
|
np.round(
|
|
np.logspace(
|
|
start=math.log(1, 10),
|
|
stop=math.log(len(distances) - 1, 10),
|
|
num=nr_levels,
|
|
)
|
|
)
|
|
.astype(int)
|
|
.tolist()
|
|
)
|
|
log_indices.reverse()
|
|
max_distances = [distances[i] for i in log_indices]
|
|
elif level_scale == "lin" or level_scale == "linear":
|
|
max_distances = [
|
|
distances[indices[-1]] for indices in np.array_split(range(len(hierarchical_topics)), nr_levels)
|
|
][::-1]
|
|
else:
|
|
raise ValueError("level_scale needs to be one of 'log' or 'linear'")
|
|
|
|
for index, max_distance in enumerate(max_distances):
|
|
# Get topics below `max_distance`
|
|
mapping = {topic: topic for topic in df.topic.unique()}
|
|
selection = hierarchical_topics.loc[hierarchical_topics.Distance <= max_distance, :]
|
|
selection.Parent_ID = selection.Parent_ID.astype(int)
|
|
selection = selection.sort_values("Parent_ID")
|
|
|
|
for row in selection.iterrows():
|
|
for topic in row[1].Topics:
|
|
mapping[topic] = row[1].Parent_ID
|
|
|
|
# Make sure the mappings are mapped 1:1
|
|
mappings = [True for _ in mapping]
|
|
while any(mappings):
|
|
for i, (key, value) in enumerate(mapping.items()):
|
|
if value in mapping.keys() and key != value:
|
|
mapping[key] = mapping[value]
|
|
else:
|
|
mappings[i] = False
|
|
|
|
# Create new column
|
|
df[f"level_{index + 1}"] = df.topic.map(mapping)
|
|
df[f"level_{index + 1}"] = df[f"level_{index + 1}"].astype(int)
|
|
|
|
# Prepare topic names of original and merged topics
|
|
trace_names = []
|
|
topic_names = {}
|
|
for topic in range(hierarchical_topics.Parent_ID.astype(int).max()):
|
|
if topic < hierarchical_topics.Parent_ID.astype(int).min():
|
|
if topic_model.get_topic(topic):
|
|
if isinstance(custom_labels, str):
|
|
trace_name = f"{topic}_" + "_".join(
|
|
list(zip(*topic_model.topic_aspects_[custom_labels][topic]))[0][:3]
|
|
)
|
|
elif topic_model.custom_labels_ is not None and custom_labels:
|
|
trace_name = topic_model.custom_labels_[topic + topic_model._outliers]
|
|
else:
|
|
trace_name = f"{topic}_" + "_".join([word[:20] for word, _ in topic_model.get_topic(topic)][:3])
|
|
topic_names[topic] = {
|
|
"trace_name": trace_name[:40],
|
|
"plot_text": trace_name[:40],
|
|
}
|
|
trace_names.append(trace_name)
|
|
else:
|
|
trace_name = (
|
|
f"{topic}_"
|
|
+ hierarchical_topics.loc[hierarchical_topics.Parent_ID == str(topic), "Parent_Name"].values[0]
|
|
)
|
|
plot_text = "_".join([name[:20] for name in trace_name.split("_")[:3]])
|
|
topic_names[topic] = {
|
|
"trace_name": trace_name[:40],
|
|
"plot_text": plot_text[:40],
|
|
}
|
|
trace_names.append(trace_name)
|
|
|
|
# Prepare traces
|
|
all_traces = []
|
|
for level in range(len(max_distances)):
|
|
traces = []
|
|
|
|
# Outliers
|
|
if topic_model._outliers:
|
|
traces.append(
|
|
go.Scattergl(
|
|
x=df.loc[(df[f"level_{level + 1}"] == -1), "x"],
|
|
y=df.loc[df[f"level_{level + 1}"] == -1, "y"],
|
|
mode="markers+text",
|
|
name="other",
|
|
hoverinfo="text",
|
|
hovertext=df.loc[(df[f"level_{level + 1}"] == -1), "doc"] if not hide_document_hover else None,
|
|
showlegend=False,
|
|
marker=dict(color="#CFD8DC", size=5, opacity=0.5),
|
|
)
|
|
)
|
|
|
|
# Selected topics
|
|
if topics:
|
|
selection = df.loc[(df.topic.isin(topics)), :]
|
|
unique_topics = sorted([int(topic) for topic in selection[f"level_{level + 1}"].unique()])
|
|
else:
|
|
unique_topics = sorted([int(topic) for topic in df[f"level_{level + 1}"].unique()])
|
|
|
|
for topic in unique_topics:
|
|
if topic != -1:
|
|
if topics:
|
|
selection = df.loc[(df[f"level_{level + 1}"] == topic) & (df.topic.isin(topics)), :]
|
|
else:
|
|
selection = df.loc[df[f"level_{level + 1}"] == topic, :]
|
|
|
|
if not hide_annotations:
|
|
selection.loc[len(selection), :] = None
|
|
selection["text"] = ""
|
|
selection.loc[len(selection) - 1, "x"] = selection.x.mean()
|
|
selection.loc[len(selection) - 1, "y"] = selection.y.mean()
|
|
selection.loc[len(selection) - 1, "text"] = topic_names[int(topic)]["plot_text"]
|
|
|
|
traces.append(
|
|
go.Scattergl(
|
|
x=selection.x,
|
|
y=selection.y,
|
|
text=selection.text if not hide_annotations else None,
|
|
hovertext=selection.doc if not hide_document_hover else None,
|
|
hoverinfo="text",
|
|
name=topic_names[int(topic)]["trace_name"],
|
|
mode="markers+text",
|
|
marker=dict(size=5, opacity=0.5),
|
|
)
|
|
)
|
|
|
|
all_traces.append(traces)
|
|
|
|
# Track and count traces
|
|
nr_traces_per_set = [len(traces) for traces in all_traces]
|
|
trace_indices = [(0, nr_traces_per_set[0])]
|
|
for index, nr_traces in enumerate(nr_traces_per_set[1:]):
|
|
start = trace_indices[index][1]
|
|
end = nr_traces + start
|
|
trace_indices.append((start, end))
|
|
|
|
# Visualization
|
|
fig = go.Figure()
|
|
for traces in all_traces:
|
|
for trace in traces:
|
|
fig.add_trace(trace)
|
|
|
|
for index in range(len(fig.data)):
|
|
if index >= nr_traces_per_set[0]:
|
|
fig.data[index].visible = False
|
|
|
|
# Create and add slider
|
|
steps = []
|
|
for index, indices in enumerate(trace_indices):
|
|
step = dict(
|
|
method="update",
|
|
label=str(index),
|
|
args=[{"visible": [False] * len(fig.data)}],
|
|
)
|
|
for index in range(indices[1] - indices[0]):
|
|
step["args"][0]["visible"][index + indices[0]] = True
|
|
steps.append(step)
|
|
|
|
sliders = [dict(currentvalue={"prefix": "Level: "}, pad={"t": 20}, steps=steps)]
|
|
|
|
# Add grid in a 'plus' shape
|
|
x_range = (
|
|
df.x.min() - abs((df.x.min()) * 0.15),
|
|
df.x.max() + abs((df.x.max()) * 0.15),
|
|
)
|
|
y_range = (
|
|
df.y.min() - abs((df.y.min()) * 0.15),
|
|
df.y.max() + abs((df.y.max()) * 0.15),
|
|
)
|
|
fig.add_shape(
|
|
type="line",
|
|
x0=sum(x_range) / 2,
|
|
y0=y_range[0],
|
|
x1=sum(x_range) / 2,
|
|
y1=y_range[1],
|
|
line=dict(color="#CFD8DC", width=2),
|
|
)
|
|
fig.add_shape(
|
|
type="line",
|
|
x0=x_range[0],
|
|
y0=sum(y_range) / 2,
|
|
x1=x_range[1],
|
|
y1=sum(y_range) / 2,
|
|
line=dict(color="#9E9E9E", width=2),
|
|
)
|
|
fig.add_annotation(x=x_range[0], y=sum(y_range) / 2, text="D1", showarrow=False, yshift=10)
|
|
fig.add_annotation(y=y_range[1], x=sum(x_range) / 2, text="D2", showarrow=False, xshift=10)
|
|
|
|
# Stylize layout
|
|
fig.update_layout(
|
|
sliders=sliders,
|
|
template="simple_white",
|
|
title={
|
|
"text": f"{title}",
|
|
"x": 0.5,
|
|
"xanchor": "center",
|
|
"yanchor": "top",
|
|
"font": dict(size=22, color="Black"),
|
|
},
|
|
width=width,
|
|
height=height,
|
|
)
|
|
|
|
fig.update_xaxes(visible=False)
|
|
fig.update_yaxes(visible=False)
|
|
return fig
|