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Enum “Inheritance”
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This is not possible. Enums cannot inherit from other enums. In fact all enums must actually inherit from System.Enum. C# allows syntax to change the underlying representation of the enum values which looks like inheritance, but in actuality they still inherit from System.enum.
See section 8...
How to normalize a NumPy array to within a certain range?
...p.max(np.abs(audio),axis=0)
image *= (255.0/image.max())
Using /= and *= allows you to eliminate an intermediate temporary array, thus saving some memory. Multiplication is less expensive than division, so
image *= 255.0/image.max() # Uses 1 division and image.size multiplications
is margi...
What are the relationships between Any, AnyVal, AnyRef, Object and how do they map when used in Java
I usually end up trying every combination until it compiles. Can somebody explain what I should use where?
3 Answers
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Simulate CREATE DATABASE IF NOT EXISTS for PostgreSQL?
...an work around it from within psql by executing the DDL statement conditionally:
SELECT 'CREATE DATABASE mydb'
WHERE NOT EXISTS (SELECT FROM pg_database WHERE datname = 'mydb')\gexec
The manual:
\gexec
Sends the current query buffer to the server, then treats each column of each row of the query's...
Simple explanation of clojure protocols
...eployed, separately type checked. We want them to be type-safe. [Note: not all of these make sense in all languages. But, for example, the goal to have them type-safe makes sense even in a language like Clojure. Just because we can't statically check type-safety doesn't mean that we want our code to...
Can you help me understand Moq Callback?
Using Moq and looked at Callback but I have not been able to find a simple example to understand how to use it.
5 Answers...
byte + byte = int… why?
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The third line of your code snippet:
byte z = x + y;
actually means
byte z = (int) x + (int) y;
So, there is no + operation on bytes, bytes are first cast to integers and the result of addition of two integers is a (32-bit) integer.
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Clone only one branch [duplicate]
... do not point into the history of the branch are not fetched.
Git actually allows you to clone only one branch, for example:
git clone -b mybranch --single-branch git://sub.domain.com/repo.git
Note: Also you can add another single branch or "undo" this action.
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Exclude a directory from git diff
...t diff previous_release current_release !(spec)
Saves you having to list all other things.
Or, shell-agnostic:
git diff previous_release current_release --name-only | grep -v '^spec/' \
| xargs git diff previous_release current_release --
You could wrap that up in a one-liner shell script ...
Environment variable to control java.io.tmpdir?
...s.
On Windows, OpenJDK's get_temp_directory() function makes a Win32 API call to GetTempPath(); this is how on Windows, Java reflects the value of the TMP environment variable.
On Linux and Solaris, the same get_temp_directory() functions return a static value of /tmp/.
I don't know if the actual...