Plotly Animation with slider - plotly-python

Question

I want to add two moving points represent the location of two trains according to the day. My day data is as shown in pic starting from 0 to 7. However, in the resulting animation, the slider does not slide into the integer day. It jumped from 1.75 to 2.25 or 2.75 to 3.25 automatically. Can anyone help me to solve that?
trainpath info
import plotly.graph_objects as go
import pandas as pd
dataset = pd.read_csv('trainpath.csv')
days = []
for k in range(len(dataset['day'])):
if dataset['day'][k] not in days:
days.append(dataset['day'][k])
t1 = [-1, 0, 1, 1, 1, 0, -1, -1, -1]
k1 = [-20, -20, -20, 0, 20, 20, 20, 0, -20]
# make list of trains
trains = []
for train in dataset["train"]:
if train not in trains:
trains.append(train)
# make figure
fig_dict = {
"data": [go.Scatter(x=t1, y=k1,
mode="lines",
line=dict(width=2, color="blue")),
go.Scatter(x=t1, y=k1,
mode="lines",
line=dict(width=2, color="blue"))],
"layout": {},
"frames": []
}
# fill in most of layout
fig_dict['layout']['title'] = {'text':'Train Animation'}
fig_dict["layout"]["xaxis"] = {"range": [-10, 10], "title": "xlocation", 'autorange':False, 'zeroline':False}
fig_dict["layout"]["yaxis"] = {"range": [-22, 22], "title": "ylocation", 'autorange':False, 'zeroline':False}
fig_dict["layout"]["hovermode"] = "closest"
fig_dict["layout"]["updatemenus"] = [
{
"buttons": [
{
"args": [None, {"frame": {"duration": 500, "redraw": False},
"fromcurrent": True, "transition": {"duration": 300,
"easing": "quadratic-in-out"}}],
"label": "Play",
"method": "animate"
},
{
"args": [[None], {"frame": {"duration": 0, "redraw": False},
"mode": "immediate",
"transition": {"duration": 0}}],
"label": "Pause",
"method": "animate"
}
],
"direction": "left",
"pad": {"r": 10, "t": 87},
"showactive": False,
"type": "buttons",
"x": 0.1,
"xanchor": "right",
"y": 0,
"yanchor": "top"
}
]
sliders_dict = {
"active": 0,
"yanchor": "top",
"xanchor": "left",
"currentvalue": {
"font": {"size": 20},
"prefix": "Day:",
"visible": True,
"xanchor": "right"
},
"transition": {"duration": 300, "easing": "cubic-in-out"},
"pad": {"b": 10, "t": 50},
"len": 0.9,
"x": 0.1,
"y": 0,
"steps": []
}
# make data
day = 0
for train in trains:
dataset_by_date = dataset[dataset['day']==day]
dataset_by_date_and_train = dataset_by_date[dataset_by_date['train']==train]
data_dict = {
'x': list(dataset_by_date_and_train['x']),
'y': list(dataset_by_date_and_train['y']),
'mode': 'markers',
'text': train,
'marker': {
'sizemode': 'area',
'sizeref': 20,
'size': 20,
# 'size': list(dataset_by_date_and_train['quantity']) # this section can be used to increase or decrease the marker size to reflect the material quantity
},
'name': train
}
fig_dict['data'].append(data_dict)
# make frames
for day in days:
frame={'data': [go.Scatter(x=t1, y=k1,
mode="lines",
line=dict(width=2, color="blue")),
go.Scatter(x=t1, y=k1,
mode="lines",
line=dict(width=2, color="blue"))], 'name':str(day)}
for train in trains:
dataset_by_date = dataset[dataset['day'] == day]
dataset_by_date_and_train = dataset_by_date[dataset_by_date['train'] == train]
data_dict = {
'x': list(dataset_by_date_and_train['x']),
'y': list(dataset_by_date_and_train['y']),
'mode': 'markers',
'text': train,
'marker': {
'sizemode': 'area',
'sizeref': 20,
'size': 20,
# 'size': list(dataset_by_date_and_train['quantity']) # this section can be used to increase or decrease the marker size to reflect the material quantity
},
'name': train
}
frame['data'].append(data_dict)
fig_dict['frames'].append(frame)
slider_step = {'args': [
[day],
{'frame': {'duration':300, 'redraw':False},
'mode': 'immediate',
'transition': {'duration':3000}}
],
'label': day,
'method': 'animate'}
sliders_dict["steps"].append(slider_step)
if day == 7:
print('H')
fig_dict["layout"]["sliders"] = [sliders_dict]
fig = go.Figure(fig_dict)
fig.show()