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How to get execution time in rails console?
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edited Jul 20 '19 at 4:28
Jeremy Baker
3,04833 gold badges2121 silver badges2525 bronze badges
answere...
How to add “on delete cascade” constraints?
In PostgreSQL 8 is it possible to add ON DELETE CASCADES to the both foreign keys in the following table without dropping the latter?
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promise already under evaluation: recursive default argument reference or earlier problems?
...on(x, T) {
10 * sin(0.3 * x) * sin(1.3 * x^2) + 0.001 * x^3 + 0.2 * x + 80
}
g <- function(x, T, f. = f) { ## 1. note f.
exp(-f.(x)/T)
}
test<- function(g. = g, T = 1) { ## 2. note g.
g.(1,T)
}
test()
## [1] 8.560335e-37
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How to remove duplicate values from a multi-dimensional array in PHP
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edited Mar 6 '15 at 16:28
jeromegamez
2,6911919 silver badges3434 bronze badges
answered Jun 3 '09 at ...
In Python, how do you convert seconds since epoch to a `datetime` object?
...output as with time.gmtime
>>> datetime.datetime.fromtimestamp(1284286794)
datetime.datetime(2010, 9, 12, 11, 19, 54)
or
>>> datetime.datetime.utcfromtimestamp(1284286794)
datetime.datetime(2010, 9, 12, 10, 19, 54)
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How to use the 'sweep' function
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85
sweep() is typically used when you operate a matrix by row or by column, and the other input of...
Java: PrintStream to String?
...eArrayOutputStream baos = new ByteArrayOutputStream();
final String utf8 = StandardCharsets.UTF_8.name();
try (PrintStream ps = new PrintStream(baos, true, utf8)) {
yourFunction(object, ps);
}
String data = baos.toString(utf8);
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Python's “in” set operator
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85
That's right. You could try it in the interpreter like this:
>>> a_set = set(['a', 'b...
How to get first N elements of a list in C#?
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answered Nov 26 '08 at 7:28
Matt HamiltonMatt Hamilton
183k5959 gold badges376376 silver badges317317 bronze badges
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How can we programmatically detect which iOS version is device running on? [duplicate]
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684
Best current version, without need to deal with numeric search within NSString is to define mac...