2.4.2.B.sagews

from sympy.physics.units import *
from sympy import *
from sympy import N as Num

print("\n--- User input -----------------------")

symbolic = True
symbolic = False

if symbolic:
    # quantity = symbol:
    a, F, E, I = var("a, F, E, I")
else:
    # quantity =  factor times unit:
    a = S(4)/10 *m
    F = 5 *kilo*newton
    E = 210 *giga*pascal
    I = (26 + S(5)/10) *cm**4

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

print("\n--- b: -------------------------------")
x=var("x")
M = - 2*F/5*x

print("\n--- c: -------------------------------")
C1, C2 = var("C1, C2")

EI_w_pp = - M
EI_w_p  = integrate(EI_w_pp,x) + C1
EI_w    = integrate(EI_w_p,x) + C2

print("\n--- d: -------------------------------")
eq1 = Eq(EI_w.subs(x,0*a), 0)
eq2 = Eq(EI_w.subs(x,5*a), 0)

sol = solve([eq1, eq2], [C1, C2])

EI_w = EI_w.subs([(C1, sol[C1]), (C2, sol[C2])])

# Displacement:
w = EI_w/E/I

pprint(["w(x): ", w.simplify()])
print("\n--- e: -------------------------------")

w=w.simplify().subs(x,5*a/2)
if not (symbolic):
    pprint(["w(5a/2): ", Num(w,3)])
else: # use symbols:
    pprint(["w(5a/2): ", w])

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

--- User input ----------------------- --- a: ------------------------------- --- b: ------------------------------- --- c: ------------------------------- --- d: ------------------------------- 3 20*x 80*x [w(x): , ------- - ----] 2 3339 3339*m --- e: ------------------------------- [w(5a/2): , -0.018*m] --- f: -------------------------------