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What's the function like sum() but for multiplication? product()?
...our data consists of floats, you can compute a product using sum() with exponents and logarithms:
>>> from math import log, exp
>>> data = [1.2, 1.5, 2.5, 0.9, 14.2, 3.8]
>>> exp(sum(map(log, data)))
218.53799999999993
>>> 1.2 * 1.5 * 2.5 * 0.9 * 14.2 * 3.8
218....
Is there still any reason to learn AWK?
I am constantly learning new tools, even old fashioned ones, because I like to use the right solution for the problem.
24 A...
What is the difference between dict.items() and dict.iteritems() in Python2?
...hod named iteritems(). The original remains for backwards compatibility.
One of Python 3’s changes is that items() now return iterators, and a list is never fully built. The iteritems() method is also gone, since items() in Python 3 works like viewitems() in Python 2.7.
...
Why are elementwise additions much faster in separate loops than in a combined loop?
... clock_t start = clock();
int c = 0;
while (c++ < 10000){
#if ONE_LOOP
for(int j=0;j<n;j++){
a1[j] += b1[j];
c1[j] += d1[j];
}
#else
for(int j=0;j<n;j++){
a1[j] += b1[j];
}
for(int j=0;j<n;j++){
...
Why would one use nested classes in C++?
Can someone please point me towards some nice resources for understanding and using nested classes? I have some material like Programming Principles and things like this IBM Knowledge Center - Nested Classes
...
List of standard lengths for database fields
...irst name.
Email addresses maxed out at 62
characters. Most of the longer ones
were actually lists of email
addresses separated by semicolons.
Street address maxes out at 95
characters. The long ones were all
valid.
Max city length was 35.
This should be a decent statistical spread for people in...
Regex to validate password strength
...has two uppercase letters.
(?=.*[!@#$&*]) Ensure string has one special case letter.
(?=.*[0-9].*[0-9]) Ensure string has two digits.
(?=.*[a-z].*[a-z].*[a-z]) Ensure string has three lowercase letters.
.{8} Ensure string is of length 8.
$ ...
How can I get the concatenation of two lists in Python without modifying either one? [duplicate]
...eturns the concatenation of the lists:
concat = first_list + second_list
One disadvantage of this method is that twice the memory is now being used . For very large lists, depending on how you're going to use it once it's created, itertools.chain might be your best bet:
>>> import iterto...
LINQ: Not Any vs All Don't
Often I want to check if a provided value matches one in a list (e.g. when validating):
8 Answers
...
Semaphore vs. Monitors - what's the difference?
...ions or methods of a monitor object will enforce mutual exclusion, so only one thread may be performing any action on the object at a given time. If one thread is currently executing a member function of the object then any other thread that tries to call a member function of that object will have t...