在甘特图上显示问题（Jupyter，Plotly，Python）

Question

I'm trying the plotly library and I made a Gantt chart in jupyter with a fake list of students and when they enter/exit a language school.

The create_gantt method interpreted the data correctly but the display is somehow cropped on the left. Only 11 characters or so from the full names are displayed.

If you look closely on the page https://plot.ly/python/gantt/ in "Out[7]:" the M of the task "Morning Sleep" is also cropped.

I found no arguments in the method to change this. I also tried modifiying jupyter's display properties and it didn't affect the chart:

from IPython.core.display import display, HTML
display(HTML("<style>.container { width:100%; }</style>"))

Does someone have an idea to fix this? Thank you very much :).

Here's the code:

import pandas as pd
from plotly.offline import init_notebook_mode, iplot
from plotly.graph_objs import *
init_notebook_mode(connected=True)  # initiate notebook for offline plot
import plotly.figure_factory as ff

df_gantt2 =pd.DataFrame([
{'Task': 'Anthony Clark', 'Start': '2017-12-13', 'Finish': '2018-02-23'},
{'Task': 'Ariosto Li Fonti', 'Start': '2017-12-15', 'Finish': '2018-01-23'},
{'Task': 'Cettina Trevisano', 'Start': '2017-12-20', 'Finish': '2018-03-08'},
{'Task': 'Dora Padovesi', 'Start': '2018-01-11', 'Finish': '2018-01-12'},
{'Task': 'Emmeline Déziel', 'Start': '2018-01-22', 'Finish': '2018-03-25'},
{'Task': 'Sawa Tretyakov', 'Start': '2018-12-03', 'Finish': '2018-12-31'},])

fig = ff.create_gantt(df_gantt2, colors=['#333F44', '#93e4c1'],title='Students\' presence (those are fake names)',show_colorbar=True, bar_width=0.2, showgrid_x=True, showgrid_y=True)
iplot(fig,filename = 'students-presence-gantt')

Answer 1

so I figured out there is a forum for plotly and someone answered there ( https://community.plot.ly/t/gantt-cropped-text/7053/3 ).

I managed to solve the problem programmatically. I calculate the max width of the task column in pixel using a function. After creating the chart I use an uptade method and give the max width as an argument. Then I display the chart.

def max_length_col(column,font='OpenSans-Regular.ttf', font_size=14):
'''Calculates the max length of a column of a dataframe / a panda serie in pixels.
Default keyword arguments values are useful to adapt the length of the y axis of a plotly gantt chart.

Args:
    column: panda serie
    font: ttf filename (look under ...\Windows\Font, get the exact name by right-clicking on a ttf file and then go to properties)
    font_size : font size as an int

Example:
    In:
        df_gantt =pd.DataFrame([
        {'Task': 'Anthony Clark', 'Start': '2017-12-13', 'Finish': '2018-02-23'},
        {'Task': 'Ariosto Li Fonti', 'Start': '2017-12-15', 'Finish': '2018-01-23'},
        {'Task': 'Cettina Trevisano', 'Start': '2017-12-20', 'Finish': '2018-03-08'}])
        column_len = max_length_col(df_gantt['Task'])
        print(column_len)
    Out:
        117

Returns:
    Length of the column in pixel as an int
'''
from PIL import ImageFont #pip install pillow
font = ImageFont.truetype(font,font_size) # should already be installed, if not download it and save under Windows/Font
length_list = []
for row in range(len(column)):
    text = str(column[row])
    size = font.getsize(text)
    length_list.append(size[0]) # append length in pixel (size[1] for heigth)
max_length_px = max(length_list)
return max_length_px

import pandas as pd
from plotly.offline import init_notebook_mode, iplot
from plotly.graph_objs import *
init_notebook_mode(connected=True)  # initiate notebook for offline plot
import plotly.figure_factory as ff

df_gantt2 =pd.DataFrame([
{'Task': 'Anthony Clark', 'Start': '2017-12-13', 'Finish': '2018-02-23'},
{'Task': 'Ariosto Li Fonti', 'Start': '2017-12-15', 'Finish': '2018-01-23'},
{'Task': 'Cettina Trevisano', 'Start': '2017-12-20', 'Finish': '2018-03-08'},
{'Task': 'Dora Padovesi', 'Start': '2018-01-11', 'Finish': '2018-01-12'},
{'Task': 'Emmeline Déziel', 'Start': '2018-01-22', 'Finish': '2018-03-25'},
{'Task': 'Sawa Tretyakov', 'Start': '2018-12-03', 'Finish': '2018-12-31'},])

fig = ff.create_gantt(df_gantt2, colors=['#333F44', '#93e4c1'],title='Students\' presence (those are fake names)',show_colorbar=True, bar_width=0.2, showgrid_x=True, showgrid_y=True)

column_len = df_gantt2['Task']
max_length_px = max_length_col(column_len)

fig['layout'].update(autosize=False, width=800, height=500, margin=dict(l=max_length_px)) 
#Insert this line just after fig=ff.create_gantt
iplot(fig,filename = 'students-presence-gantt')