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Why C# implements methods as non-virtual by default?
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Classes should be designed for inheritance to be able to take advantage of it. Having methods v...
LINQ order by null column where order is ascending and nulls should be last
... edited Aug 21 '13 at 18:35
abc123
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answered Jun 23 '11 at 22:52
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How to convert an NSString into an NSNumber
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For strings starting with integers, e.g., @"123", @"456 ft", @"7.89", etc., use -[NSString integerValue].
So, @([@"12.8 lbs" integerValue]) is like doing [NSNumber numberWithInteger:12].
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Join a list of items with different types as string in Python
...o combine list into a single string
a = map(str, a)
''.join(a)
'123'
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In Typescript, How to check if a string is Numeric
...y to convert a string to a number is with Number, not parseFloat.
Number('1234') // 1234
Number('9BX9') // NaN
You can also use the unary plus operator if you like shorthand:
+'1234' // 1234
+'9BX9' // NaN
Be careful when checking against NaN (the operator === and !== don't work as expected wi...
MySql: Tinyint (2) vs tinyint(1) - what is the difference?
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It means display width
Whether you use tinyint(1) or tinyint(2), it does not make any differen...
Is there a way to perform “if” in python's lambda
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David WoleverDavid Wolever
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'npm' is not recognized as internal or external command, operable program or batch file
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Don't forget to reboot your computer after installing node! That one got me.
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What is the minimum valid JSON?
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Mark Amery
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answered Aug 24 '13 at 14:18
IMSoPIMSoP...
Remove duplicated rows
...for larger data sets
library(microbenchmark)
library(data.table)
set.seed(123)
DF <- as.data.frame(matrix(sample(1e8, 1e5, replace = TRUE), ncol = 10))
DT <- copy(DF)
setDT(DT)
microbenchmark(unique(DF), unique(DT))
# Unit: microseconds
# expr min lq mean median ...