Refreshing a matplolib plot on a flask app after updating dataset

Question

I have been using the suggestion here:

How to render and return plot to view in flask?

to create a plot in my flask app.

In the app I can update the actual values in the data set, and the plot updates respectively, BUT the 'previous plot line' does not.

I tried saving the file as a static plot in a folder, but then the updated data is not refreshed.

Any suggestions will be appreciated.

may be after adding the code in your question, we find some reasons. your methodology of storing new graph and represent that graph is good. — Nour-Allah Hussein, Dec 29 '20 at 16:10

score 0 · Accepted Answer · answered Dec 29 '20 at 17:21

I just found this link that offers a solution for my problem.

Basically, changing the basic code in the link in the question:

img = io.BytesIO() 
sns.set_style("dark")
plt.plot(df.Date, df.Value) 
plt.savefig(img, format='png', transparent = True) 
img.seek(0)   
plot_url = base64.b64encode(img.getvalue()).decode()

to:

fig,ax=plt.subplots(figsize=(6,6))
ax=sns.set(style="darkgrid")
sns.lineplot(df.Date, df.Value)
canvas=FigureCanvas(fig)
img = io.BytesIO()
fig.savefig(img,transparent = True)
img.seek(0)
plot_url = base64.b64encode(img.getvalue()).decode()

Refreshing a matplolib plot on a flask app after updating dataset

1 Answers1