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Creating a new column based on if-elif-else condition
...tion that operates on the rows of your dataframe like so:
def f(row):
if row['A'] == row['B']:
val = 0
elif row['A'] > row['B']:
val = 1
else:
val = -1
return val
Then apply it to your dataframe passing in the axis=1 option:
In [1]: df['C'] = df.apply(f...
Is std::unique_ptr required to know the full definition of T?
...ve code like the above. When it executes, bad things will probably happen. If you're very lucky your program will crash. However a more probable outcome is that your program will silently leak memory as ~A() won't be called.
Using auto_ptr<A> in the above example doesn't help. You still get t...
How should one go about choosing a default TCP/IP port for a new service?
...
If all developers go by that logic it would mean that all new services gather around the few unassigned ports. What would the probability be that a service is running on an assigned port vs an unassigned port. (Sorry if I'm...
IPN vs PDT in Paypal
I'm having some trouble choosing between PayPal's Instant Payment Notification (IPN) and Payment Data Transfer (PDT).
3 Ans...
Detecting design mode from a Control's constructor
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@Filip Kunc: if this doesn't work in OnPaint, you may check this condition in constructor and store it in a class field.
– IMil
Apr 6 '16 at 18:37
...
django MultiValueDictKeyError error, how do I deal with it
... on standard dicts and is a way to fetch a value while providing a default if it does not exist.
is_private = request.POST.get('is_private', False)
Generally,
my_var = dict.get(<key>, <default>)
share
...
XPath to find elements that does not have an id or class
...
That will give you all tr elements lacking both id and class attributes. If you want all tr elements lacking one of the two, use or instead of and:
//tr[not(@id) or not(@class)]
When attributes and elements are used in this way, if the attribute or element has a value it is treated as if it's t...
Changing the interval of SetInterval while it's running
...llback = function(tick, counter) {
return function() {
if (--tick >= 0) {
window.setTimeout(internalCallback, ++counter * factor);
callback();
}
}
}(times, 0);
window.setTimeout(internalCallback, factor);
};
// cons...
Use PHP composer to clone git repo
...S TO THE REPOSITORY?
Yes?
DOES THE REPOSITORY HAVE A composer.json FILE
If you have a repository you can write to: Add a composer.json file, or fix the existing one, and DON'T use the solution below.
Go to @igorw 's answer
ONLY USE THIS IF YOU DON'T HAVE A REPOSITORY
OR IF THE REPOSITORY DOES N...
MySql : Grant read only options?
...
If there is any single privilege that stands for ALL READ operations on database.
It depends on how you define "all read."
"Reading" from tables and views is the SELECT privilege. If that's what you mean by "all read" then...