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Why does Math.round(0.49999999999999994) return 1?
....1 This is a specification bug, for precisely this one pathological case.2 Java 7 no longer mandates this broken implementation.3
The problem
0.5+0.49999999999999994 is exactly 1 in double precision:
static void print(double d) {
System.out.printf("%016x\n", Double.doubleToLongBits(d));
}
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Why does ~True result in -2?
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240
int(True) is 1.
1 is:
00000001
and ~1 is:
11111110
Which is -2 in Two's complement1
1 ...
Aggregate / summarize multiple variables per group (e.g. sum, mean)
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Where is this year() function from?
You could also use the reshape2 package for this task:
require(reshape2)
df_melt <- melt(df1, id = c("date", "year", "month"))
dcast(df_melt, year + month ~ variable, sum)
# year month x1 x2
1 2000 1 -80.83405 -224.9540159
2 ...
How to extract the n-th elements from a list of tuples?
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edited Mar 6 '19 at 20:33
cs95
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answer...
Centering controls within a form in .NET (Winforms)? [duplicate]
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254
You could achieve this with the use of anchors. Or more precisely the non use of them.
Contr...
How do you test that a Python function throws an exception?
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724
Use TestCase.assertRaises (or TestCase.failUnlessRaises) from the unittest module, for example:...
How to escape braces (curly brackets) in a format string in .NET
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1295
For you to output foo {1, 2, 3} you have to do something like:
string t = "1, 2, 3";
string v...
New Array from Index Range Swift
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This works for me:
var test = [1, 2, 3]
var n = 2
var test2 = test[0..<n]
Your issue could be with how you're declaring your array to begin with.
EDIT:
To fix your function, you have to cast your Slice to an array:
func aFunction(numbers: Array<Int...
Standard deviation of a list
I want to find mean and standard deviation of 1st, 2nd,... digits of several (Z) lists. For example, I have
8 Answers
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