Python Panel passing a dataframe in param.Parameterized class
I can build a dashboard using panel. I know want to include the code in a class including the data manipulation.
df = ydata.load_web(rebase=True)
class Plot(param.Parameterized):
df = df
col = list(df.columns)
Index1 = param.ListSelector(default=col, objects=col)
Index2 = param.ListSelector(default=col[1:2], objects=col)
def dashboard(self, **kwargs):
unds = list(set(self.Index1 + self.Index2))
return self.df[unds].hvplot()
b = Plot(name="Index Selector")
pn.Row(b.param, b.dashboard)
I would like to call
b = Plot(name="Index Selector", df=ydata.load_web(rebase=True))
Using a parameterized DataFrame and two methods for
the code could look like this:
# Test data frame with two columns
df = pd.DataFrame(np.random.randint(90,100,size=(100, 1)), columns=['1'])
df['2'] = np.random.randint(70,80,size=(100, 1))
class Plot(param.Parameterized):
df = param.DataFrame(precedence=-1) # precedence <1, will not be shown as widget
df_columns = param.ListSelector(default=[], objects=[], label='DataFrame columns')
def __init__(self, **params):
super(Plot, self).__init__(**params)
# set the column selector with the data frame provided at initialization
self.set_df_columns_selector()
# method is triggered each time the data frame changes
@param.depends('df', watch=True)
def set_df_columns_selector(self):
col = list(self.df.columns)
print('Set the df index selector when the column list changes: {}'.format(col))
self.param.df_columns.objects = list(col) # set choosable columns according current df
self.df_columns = [self.param.df_columns.objects[0]] # set column 1 as default
# method is triggered each time the choosen columns change
@param.depends('df_columns', watch=True)
def set_plots(self):
print('Plot the columns choosen by the df column selector: {}'.format(self.df_columns))
plotlist = [] # start with empty list
for i in self.df_columns:
# append plot for each choosen column
plotlist.append(hv.Curve({'x': self.df.index, 'y':self.df[i]}))
self.plot = hv.Overlay(plotlist)
def dashboard(self):
return self.plot
b = Plot(name="Plot", df=df)
layout = pn.Row(b.param, b.dashboard)
layout.app()
#or:
#pn.Row(b.param, b.dashboard)
This way the parameterized variables take care of updating the plots.