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@obikag
Created February 25, 2015 00:11
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Prime number methods done in Python. First method determines if a number is prime, while the second method print to screen the first 'n' prime numbers. View comments for more information.
'''
Created on Feb 24, 2015
'''
# Method to determine if a number is a prime number
def isPrime(num):
if num <= 0 :
print("Number must be a positive integer greater than zero")
return False
elif (num == 1):
return True
'''
Prime number is divisible by itself and one,
so we check for other factors between the prime number and one. (1 < x < num)
'''
for x in range(num-1,1,-1):
if ((num % x) == 0):
return False
return True
# Method to print the first 'n' prime numbers
def printPrime(n):
count = 1
pnum = 1
while True:
if isPrime(pnum):
print(pnum)
pnum += 1
count += 1 # count only incremented when a prime number is found
else:
pnum += 1
if (count > n): break
#***Test Section***
print(isPrime(1)) #True
print(isPrime(-2)) #Number must be a positive integer greater than zero; False
print(isPrime(51)) #False
print(isPrime(3037)) #True
printPrime(10)
'''
Output:
1
2
3
5
7
11
13
17
19
23
'''
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