3.3.E.sagews

from sympy import *
from sympy import N as Num

print("--- User input ----------------------")

symbolic = True
# symbolic = False

if not (symbolic):
    #
    # factors:
    (r_val, R_val) = (1, 2.5)
    Om_val = pi/2
    #
    # quantity =  factor times unit:
    (r, R) = (r_val*m, R_val*m)
    Om = Om_val/s
else:
    # quantity = symbol:
    r, R = var("r, R")
    Om = var("Omega")

print("\n--- e: ------------------------------")

om = R/r*Om
v2 = sqrt(2)*R*Om

pprint(["om", Num(om,3)])
pprint(["v2", Num(v2,3)])

--- User input ---------------------- --- e: ------------------------------ Omega*R [om, -------] r [v2, 1.41*Omega*R]