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Declaring an enum within a class
...to have another Color enum that other classes use then you might as well make it global (or at least outside Car).
It makes no difference. If there is a global one then the local one is still used anyway as it is closer to the current scope. Note that if you define those function outside of the clas...
SQL parser library for Java [closed]
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Dave Jarvis
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answered Mar 19 '09 at 0:35
duffymoduffymo
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Selecting only numeric columns from a data frame
Suppose, you have a data.frame like this:
11 Answers
11
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How to initialize all the elements of an array to any specific value in java
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Oliver CharlesworthOliver Charlesworth
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Where is HttpContent.ReadAsAsync?
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It looks like it is an extension method (in System.Net.Http.Formatting):
HttpContentExtensions Class
Update:
PM> install-package Microsoft.AspNet.WebApi.Client
According to the System.Net.Http.Formatting NuGet package pa...
How to convert Java String into byte[]?
...ds is a byte[].
So the basic, technical answer to the question you have asked is:
byte[] b = string.getBytes();
byte[] b = string.getBytes(Charset.forName("UTF-8"));
byte[] b = string.getBytes(StandardCharsets.UTF_8); // Java 7+ only
However the problem you appear to be wrestling with is that ...
Array include any value from another array?
... & foods).empty?
As Marc-André Lafortune said in comments, & works in linear time while any? + include? will be quadratic. For larger sets of data, linear time will be faster. For small data sets, any? + include? may be faster as shown by Lee Jarvis' answer -- probably because & alloc...
How do you list the active minor modes in emacs?
...de-list. Finding out whether they're active or not is usually done by checking the variable of the same name. So you can do something like this:
(defun which-active-modes ()
"Give a message of which minor modes are enabled in the current buffer."
(interactive)
(let ((active-modes))
(map...
Macro vs Function in C
...rone because they rely on textual substitution and do not perform type-checking. For example, this macro:
#define square(a) a * a
works fine when used with an integer:
square(5) --> 5 * 5 --> 25
but does very strange things when used with expressions:
square(1 + 2) --> 1 + 2 * 1 + 2 ...
Using current time in UTC as default value in PostgreSQL
I have a column of the TIMESTAMP WITHOUT TIME ZONE type and would like to have that default to the current time in UTC. Getting the current time in UTC is easy:
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