Example python code used for the KNIME Python View node to demonstrate plot image generation using Plotly and Kaleido

knime_python_view_node_code_snippet.py

# Import modules and functions
import plotly.express as px
from plotly.offline import plot

# Apply short name to input_table dataframe
df=input_table

# Define category labels
categoryList=list(df.columns)

# Assign X as “Week No”
X = categoryList[0]

# Assign Y as the other columns
Y = categoryList[1:]


# Define the plot
fig=px.area(df,x = X, y = Y, 
	title = "Total deaths by Health Board", 
	labels={"value": "No of deaths", "variable": "Health Board"})

# Launch plot in the browser
plot(fig, auto_open=True)

# Save image as interactive HTML
fig.write_html("../../Images/stacked_area_plot_weekly_total_deaths.html")

# -------------------------------------
# Use Kaleido to generate the following static images
# Plotly will attempt to use Kaleido by default so no real need to specify engine.
# -------------------------------------

# Save image as static png
fig.write_image("../../Images/stacked_area_plot_weekly_total_deaths.png", engine="kaleido")

# Save image as static jpeg
fig.write_image("../../Images/stacked_area_plot_weekly_total_deaths.jpeg", engine="kaleido")

# Save image as static svg
fig.write_image("../../Images/stacked_area_plot_weekly_total_deaths.svg", engine="kaleido")

# Save image as static pdf
fig.write_image("../../Images/stacked_area_plot_weekly_total_deaths.pdf", engine="kaleido")

# Generate KNIME output_image
# -----------------------------------------
# Load Plotly IO module
import plotly.io as pio

# Convert figure to a static image bytes string and set output_image to this.
output_image = pio.to_image (fig, format='png', engine="kaleido")

# -----------------------------------------