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Is Python strongly typed?
...n choice made when + was implemented, but not really a necessity following from the language's semantics. In fact, when you overload + on a custom type, you can make it implicitly convert anything to a number:
def to_number(x):
"""Try to convert function argument to float-type object."""
tr...
Why should I declare a virtual destructor for an abstract class in C++?
....delete]/: ... if the static type of the object to be deleted is different from its dynamic type, ... the static type shall have a virtual destructor or the behavior is undefined. .... It would still be undefined if Derived used an implicitly generated destructor.
– Mankarse
...
How can I get sin, cos, and tan to use degrees instead of radians?
...
Multiply the input by Math.PI/180 to convert from degrees to radians before calling the system trig functions.
You could also define your own functions:
function sinDegrees(angleDegrees) {
return Math.sin(angleDegrees*Math.PI/180);
};
and so on.
...
How can I make my custom objects Parcelable?
...eator CREATOR = new Parcelable.Creator() {
public Student createFromParcel(Parcel in) {
return new Student(in);
}
public Student[] newArray(int size) {
return new Student[size];
}
};
}
Once you have created this ...
Font-awesome, input type 'submit'
... for input type 'submit' in font-awesome. Is it possible to use some class from font-awesome for button input? I've added icons to all buttons (which actually links with class 'btn' from twitter-bootstrap) in my applications, but can't add icons on 'input type submit'.
...
How to convert lazy sequence to non-lazy in Clojure
... depends on what type of non lazy sequence you want to get:
Take your pick from:
an ex-lazy (fully evaluated) lazy sequence (doall ... )
a list for sequential access (apply list (my-lazy-seq)) OR (into () ...)
a vector for later random access (vec (my-lazy-seq))
a map or a set if you h...
How to search and replace globally, starting from the cursor position and wrapping around the end of
...-&&
First, the substitution command is run for each line starting from
the current one until the end of file:
,$s/BEFORE/AFTER/gc
Then, that :substitute command is repeated with the same search
pattern, replacement string, and flags, using the :& command
(see :help :&):
1,''-&...
What are the best practices to follow when declaring an array in Javascript?
...r = [];
}());
In my example code, I've kept the Array function hidden from the rest of the document scope, however it's more likely that if you ever run into this sort of issue that the code won't have been left in a nice closure, and will likely be difficult to locate.
Disclaimer: It's not a ...
dplyr summarise: Equivalent of “.drop=FALSE” to keep groups with zero length in output
...ime, especially since your data are already factored, you can use complete from "tidyr" to get what you might be looking for:
library(tidyr)
df %>%
group_by(b) %>%
summarise(count_a=length(a)) %>%
complete(b)
# Source: local data frame [3 x 2]
#
# b count_a
# (fctr) (int)...
What's the best way to get the current URL in Spring MVC?
...UriComponentsBuilder and its static methods:
ServletUriComponentsBuilder.fromCurrentContextPath()
ServletUriComponentsBuilder.fromCurrentServletMapping()
ServletUriComponentsBuilder.fromCurrentRequestUri()
ServletUriComponentsBuilder.fromCurrentRequest()
They use RequestContextHolder under the h...