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Python: Check whether a given string is number or not using Lambda

Python Lambda: Exercise-9 with Solution

Write a Python program to check whether a given string is number or not using Lambda.

Sample Solution:

Python Code :

is_num = lambda q: q.replace('.','',1).isdigit()
print(is_num('26587'))
print(is_num('4.2365'))
print(is_num('-12547'))
print(is_num('00'))
print(is_num('A001'))
print(is_num('001'))
print("\nPrint checking numbers:")
is_num1 = lambda r: is_num(r[1:]) if r[0]=='-' else is_num(r)
print(is_num1('-16.4'))
print(is_num1('-24587.11'))

Sample Output:

True
True
False
True
False
True

Print checking numbers:
True
True

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Python: Tips of the Day

Python: Cache results with decorators

There is a great way to cache functions with decorators in Python. Caching will help save time and precious resources when there is an expensive function at hand.

Implementation is easy, just import lru_cache from functools library and decorate your function using @lru_cache.

from functools import lru_cache

@lru_cache(maxsize=None)
def fibo(a):
    if a <= 1:
        return a
    else:
        return fibo(a-1) + fibo(a-2)

for i in range(20):
    print(fibo(i), end="|")

print("\n\n", fibo.cache_info())

Output:

0|1|1|2|3|5|8|13|21|34|55|89|144|233|377|610|987|1597|2584|4181|

 CacheInfo(hits=36, misses=20, maxsize=None, currsize=20)