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BigDecimal - to use new or valueOf
...e of 1, with a scale of 1), but it is actually equal to 0.1000000000000000055511151231257827021181583404541015625. This is because 0.1 cannot be represented exactly as a double (or, for that matter, as a binary fraction of any finite length). Thus, the value that is being passed in to the constructo...
Replace a value if null or undefined in JavaScript
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Can't use modulus on doubles?
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MysticialMysticial
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Is there StartsWith or Contains in t sql with variables?
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StartsWith
a) left(@edition, 15) = 'Express Edition'
b) charindex('Express Edition', @edition) = 1
Contains
charindex('Express Edition', @edition) >= 1
Examples
left function
set @isExpress = case when left(@edition, 15) = 'Express Edition' then...
Types in MySQL: BigInt(20) vs Int(20)
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Bill KarwinBill Karwin
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getMonth in javascript gives previous month
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Rahul TripathiRahul Tripathi
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How to navigate through a vector using iterators? (C++)
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How do I declare and initialize an array in Java?
...d(0, 100).toArray(); // From 0 to 100
int [] myIntArray = IntStream.of(12,25,36,85,28,96,47).toArray(); // The order is preserved.
int [] myIntArray = IntStream.of(12,25,36,85,28,96,47).sorted().toArray(); // Sort
For classes, for example String, it's the same:
String[] myStringArray = new Strin...
Assign multiple columns using := in data.table, by group
...1 hi hello
# 2: 2 2 hi hello
# 3: 3 3 hi hello
# 4: 1 4 hi hello
# 5: 2 5 hi hello
# 6: 3 6 hi hello
x[ , c("mean", "sum") := list(mean(b), sum(b)), by = a][]
# a b col1 col2 mean sum
# 1: 1 1 hi hello 2.5 5
# 2: 2 2 hi hello 3.5 7
# 3: 3 3 hi hello 4.5 9
# 4: 1 4 h...
Rename Pandas DataFrame Index
...so here are some more examples:
In [1]: df = pd.DataFrame([[1, 2, 3], [4, 5 ,6]], columns=list('ABC'))
In [2]: df
Out[2]:
A B C
0 1 2 3
1 4 5 6
In [3]: df1 = df.set_index('A')
In [4]: df1
Out[4]:
B C
A
1 2 3
4 5 6
You can see the rename on the index, which can change...