python jupyter magic %%writefile returns SyntaxError: invalid syntax

Question

# [ ] The following program asks the user for a circle radius then display the area and circumference
# Modify the program so it only displays the information when executed directly
# The program should not display anything if it is imported as a module 


%%writefile main_script.py

def main(): 
    from math import pi

    def circle_area(r):
        return pi * (r ** 2)

    def circle_circumference(r):
        return  2 * pi * r

    radius = float(input("Enter radius: "))
    print("Area =", circle_area(radius))
    print("Circumference =", circle_circumference(radius))

if __name__="__main__":
    main()


----------
  File "<ipython-input-3-70ba6a5d5e98>", line 6
    %%writefile main_script.py
    ^
SyntaxError: invalid syntax

How do I fix this??

Its an exercise, but I just dont get how this system command works,can you explain?

ignore:for word requirements ignore:for word requirements

Justin's anwer is correct: isn't it work for you? – Meziane Mar 22 '19 at 08:19 — Meziane, Mar 22 '19 at 08:19

Justin · Answer 1 · 2018-11-29T21:23:42.013

16

This is not working for you because you have a comment in the first line(s) of your code in the notebook cell. If you move your comments underneath the magic command it will write the file.

%%writefile main_script.py

# Add all of your comments here after the magic command

def main(): 
    def add_my_code(here):
        return here

if __name__="__main__":
    main()

edited Nov 29 '18 at 21:23

answered Nov 29 '18 at 21:18

Justin

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Does this work for R kernels in Jupyter notebook ? – heisenbug47 Dec 10 '20 at 06:52

score 1 · Answer 2 · answered Sep 10 '18 at 11:10

1

%%writefile main_script.py

writefile is a command of Jupyter notebook, it's not part of a source code.

So it will give you a syntax error as a part of Python code. However, executed in Jupyter Notebook will tell it to write contents following this command to a file specified after writefile, i.e. to main_script.py

Look at how-to-append-a-file-with-a-newline-using-writefile-a-command-in-jupyter for more info

answered Sep 10 '18 at 11:10

Andrew_Lvov

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yes, I expected it to write a main_script.py. somehow it returns the error message instead...what should I do to fix it? – Karen Jiang Sep 10 '18 at 11:38
Did you paste this code inside `Jupyter Notebook` app ? – Andrew_Lvov Sep 10 '18 at 11:42
its an jupyter notebook exercise, written inside of it. – Karen Jiang Sep 10 '18 at 12:16

Anton Zubochenko · Answer 3 · 2018-09-14T17:49:46.350

0

You have to write

%%writefile

in the first line.

edited Sep 14 '18 at 17:49

answered Sep 14 '18 at 16:19

Anton Zubochenko

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the main problem is to solve EOFError. And i don't know how. You have any idea? – Anton Zubochenko Sep 14 '18 at 18:25

python jupyter magic %%writefile returns SyntaxError: invalid syntax

3 Answers3