hi, I’m using this .py example
from dash import Dash, dcc, html, Input, Output
from sklearn.model_selection import train_test_split
from sklearn.neighbors import KNeighborsClassifier
from sklearn.datasets import make_moons
import plotly.graph_objects as go
import numpy as np
app = Dash(__name__)
app.layout = html.Div([
html.H4('Explanatory k-NN plot'),
dcc.Graph(id="graph"),
html.P("Select number of neighbors:"),
dcc.Slider(
id='slider-neighbors',
min=5, max=20, step=1, value=12,
marks={i: str(i) for i in range(5,21,5)})
])
@app.callback(
Output("graph", "figure"),
Input("slider-neighbors", "value"))
def train_and_display_model(k):
X, y = make_moons(noise=0.3, random_state=0) # replace with your own data source
xrange, yrange = build_range(X, y)
xx, yy = np.meshgrid(xrange, yrange)
test_input = np.c_[xx.ravel(), yy.ravel()]
clf = KNeighborsClassifier(k, weights='uniform')
clf.fit(X, y)
Z = clf.predict_proba(test_input)[:, 1]
Z = Z.reshape(xx.shape)
fig = build_figure(X, y, Z, xrange, yrange)
return fig
# ############ HELPER FUNCTIONS ############
def build_range(X, y, mesh_size=.02, margin=.25):
"""
Create an x range and a y range for building meshgrid
"""
x_min = X[:, 0].min() - margin
x_max = X[:, 0].max() + margin
y_min = X[:, 1].min() - margin
y_max = X[:, 1].max() + margin
xrange = np.arange(x_min, x_max, mesh_size)
yrange = np.arange(y_min, y_max, mesh_size)
return xrange, yrange
def build_figure(X, y, Z, xrange, yrange):
X_train, X_test, y_train, y_test = train_test_split(
X, y.astype(str), test_size=0.25, random_state=0)
trace_specs = [
[X_train, y_train, '0', 'Train', 'square'],
[X_train, y_train, '1', 'Train', 'circle'],
[X_test, y_test, '0', 'Test', 'square-dot'],
[X_test, y_test, '1', 'Test', 'circle-dot']
]
fig = go.Figure(data=[
go.Scatter(
x=X[y==label, 0], y=X[y==label, 1],
name=f'{split}, y={label}',
mode='markers', marker_symbol=marker
)
for X, y, label, split, marker in trace_specs
])
fig.update_traces(
marker_size=12, marker_line_width=1.5,
marker_color="lightyellow"
)
fig.add_trace(
go.Contour(
x=xrange, y=yrange, z=Z,
showscale=False, colorscale='RdBu',
opacity=0.4, name='Score', hoverinfo='skip'
)
)
return fig
app.run_server(debug=True)
I’ve inserted my data, and no errors appear, but the image doesnt show … what could it be?
it shows this:
