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How to write a Unit Test?
...input.
Now, implement the test by declaring a class, name it anything (Usually something like TestAddingModule), and add the testAdd method to it (i.e. like the one below) :
Write a method, and above it add the @Test annotation.
In the method, run your binary sum and assertEquals(expectedVal,cal...
how to clear the screen in python [duplicate]
... To avoid the 0 (system's return value) being shown, use absolutely_unused_variable = os.system("cls") or absolutely_unused_variable = os.system("clear")
– Shiva
Jul 4 '15 at 8:01
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What is the difference between 'typedef' and 'using' in C++11?
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All standard references below refers to N4659: March 2017 post-Kona working draft/C++17 DIS.
Typedef declarations can, whereas alias declarations cannot, be used as initialization statements
But, with the first two non-temp...
Highlight label if checkbox is checked
...Mar 11 '11 at 17:07
Andrew MarshallAndrew Marshall
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How do I remove all non alphanumeric characters from a string except dash?
How do I remove all non alphanumeric characters from a string except dash and space characters?
13 Answers
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Java string to date conversion
...tern seems valid.
Here's an extract of relevance from the javadoc, listing all available format patterns:
Letter Date or Time Component Presentation Examples
------ ---------------------- ------------------ -------------------------------------
G Era designator Text ...
PostgreSQL: insert from another table
...
Just supply literal values in the SELECT:
INSERT INTO TABLE1 (id, col_1, col_2, col_3)
SELECT id, 'data1', 'data2', 'data3'
FROM TABLE2
WHERE col_a = 'something';
A select list can contain any value expression:
But the expressions in the select list do not have to reference any columns i...
How to list the tables in a SQLite database file that was opened with ATTACH?
....schema tablename
Print the entire table:
SELECT * FROM tablename;
List all of the available SQLite prompt commands:
.help
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What does “coalgebra” mean in the context of programming?
...coalgebras" several times in functional programming and PLT circles, especially when the discussion is about objects, comonads, lenses, and such. Googling this term gives pages that give mathematical description of these structures which is pretty much incomprehensible to me. Can anyone please expla...
Scatterplot with too many points
...;- data.frame(x = rnorm(5000),y=rnorm(5000))
ggplot(df,aes(x=x,y=y)) + geom_point(alpha = 0.3)
Another convenient way to deal with this is (and probably more appropriate for the number of points you have) is hexagonal binning:
ggplot(df,aes(x=x,y=y)) + stat_binhex()
And there is also regula...