LAB 4 Python

1)
import math
n = 0
result = 0
while True:
    try:
        n = raw_input("n=")
        n = int(n)
        x = raw_input("x=")
        x = float(x)
        if n<1:
            print "n > 0"
        else:
            break
        if x<1:
            print "x > 0"
        else:
            break
    except:
        print "NaN"
for k in range (n+1):
    result += ((-1)**k * x**(2*k))/math.factorial(2*k)
print "%f" %result

2)
import math
n = 0
result = 0
while True:
    try:
        n = raw_input("n=")
        n = int(n)
        m = raw_input("m=")
        m = float(m)
        if n<1:
            print "n > 0"
        elif m<1:
            print "m > 0"
        else:
            break
    except:
        print "NaN"
for k in range (1, n+1):
    result += (math.e ** (-m) * m ** k)/math.factorial(k)
print "%f" %result

3)
import math
n = 0
f = 0
result = 0

def getnr(name):
        r = input(name + "=")
        t = str(type(r))
        if t == "<type 'int'>" or t == "<type 'float'>":
                return float(r)
        while t != "<type 'int'>" and t != "<type 'float'>":
                print("singur int sau float");
                r = input (name + "=");
                t = str(type(r));
        if t == "<type 'int'>" or t == "<type 'float'>":
                return float(r)
while True:
    try:
        n = raw_input("n=")
        n = int(n)
        z = raw_input("z=")
        z = float(z)
        if n<1:
            print "n > 0"
        else:
            break
        if z<1:
            print "x > 0"
        else:
            break
    except:
        print "nop"

for k in range (n+1):
    #result += ((-1)**k * x**(2*k))/math.factorial(2*k)
     f += (math.factorial(4*k) * z **k) / (2**(4*k)*math.sqrt(2)*math.factorial(2*k) * math.factorial(2*k+1))
g = math.sqrt((1-math.sqrt(1-z))/z)
print "f = %f" %f
print "g = %f" %g

4)
import math
def a(n, a0):
    return math.atan((-3)*a0 + 10)
a0 = 1
while True:
    try:
        a0 = float(raw_input('a0 = '))
        if a0<0:
            print 'invalid'
        else:
            break
    except:
        print 'NaN'
eps = 1E-7
n = 1
while True:
    a1 = a(n,a0)
    if abs(a1 - a0) < eps:
        break
    a0 = a1
    n += 1
print "%f" %a0
print "%f" %a1
print "%f" %n

5)
from math import cos as cos
n=raw_input('n=')
n=int(n)
def a(n):
    return (-4**n)*(-1+cos(2**(-n)))
eps=raw_input('eps=')
eps=float(eps)
while True:
  an=a(n)
  if abs(an-1/2)<eps:
     print n;
     break;
  n+=1