Colab: Python and Sankey in Plotly

Question

I've got some simple code to test Sankey charts. It seems to stop before rendering the last "merging" flows to the last node. Any help / suggestions?

import plotly.graph_objs as go1

# one merged line - CORP01 bought CORP02
# second, occurring after first M&A - CORP04 buys CORP03
# third, occuring after second M&A - CORP04 buys CORP01

# data
source = [0,1,2,3,4,4,5,6,7,7,8,8]
target = [4,4,5,6,7,7,8,8,9,9,9,9]

# data to dict, dict to sankey
link = dict(source = source, target = target, value = value)

label = ["CORP01",   #source "0"
         "CORP02",   #source "1"
         "CORP03",   #source "2"
         "CORP04",   #source "3"
         "CORP01m",   #target "4" / source "4"
         "CORP03a",   #target "5" / source "5"
         "CORP04a",   #target "6"
         "CORP01m2",   #target "7" / source "7"
         "CORP04m",   #target "8" / source "8"
         "CORP04m2"]   #target "9"

node = dict(label = label, pad=20, thickness=10)
data = go1.Sankey(link = link, node=node)

# plot
fig = go1.Figure(data)
fig.show(renderer="colab")

The chart works until the last two flows are expected to merge into the final single node. Any thoughts?

Answer 1

As per the info from streetster - I neglected to add a list to address the value for the Sankey figure.

By adding a list for value , the chart rendered perfectly.

# data
source = [0,1,2,3,4,4,5,6,7,7,8,8]
target = [4,4,5,6,7,7,8,8,9,9,9,9]
value  = [2,2,2,2,2,2,2,2,2,2,2,2]

# data to dict, dict to sankey
link = dict(source = source, target = target, value = value)

label = ["CORP01",   #source "0"
         "CORP02",   #source "1"
         "CORP03",   #source "2"
         "CORP04",   #source "3"
         "CORP01m",   #target "4" / source "4"
         "CORP03a",   #target "5" / source "5"
         "CORP04a",   #target "6"
         "CORP01m2",   #target "7" / source "7"
         "CORP04m",   #target "8" / source "8"
         "CORP04m2"]   #target "9"

node = dict(label = label, pad=20, thickness=10)
data = go1.Sankey(link = link, node=node)

# plot
fig = go1.Figure(data)
fig.show(renderer="colab")