[SOLVED] In python, how to call a function with an argument on a click event

In python, how to call a function with an argument on a click event

I created the code below, but when I click on the click me button I get the following error message:

TypeError: 'mpfr' object is not callable

Would someone know what is wrong with the code?

import gmpy2 as g
from ipywidgets import widgets
from IPython.display import display

button = widgets.Button(description="Click Me!")
display(button)

max_precision = g.get_max_precision()
pi = g.const_pi()
g.set_context(g.context())

def set_bits_precision(decimal_precision):
    bits_precision = int(decimal_precision/g.log(2))
    if (bits_precision > max_precision): bits_precision = max_precision
    ctx = g.get_context()
    ctx.precision = bits_precision
    return

def square_root(number):
    return g.sqrt(number)

def circle_perimeter(radius):
    return 2*pi*radius 

def on_button_clicked(x):
    return square_root(x)

set_bits_precision(10)
print(pi)
button.on_click(on_button_clicked(2))

Solution

button.on_click must be given a callback function. You pass the result of on_button_clicked evaluated with parameter 2 (so, literally the square root of 2) instead of passing in a function. You can use partial function evaluation to do what you want, by replacing your last line of code with:

import functools
button.on_click(functools.partial(on_button_clicked, 2))