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Replace all 0 values to NA
I have a dataframe with some numeric columns. Some row has a 0 value which should be considered as null in statistical analysis. What is the fastest way to replace all the 0 value to NULL in R?
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What is the bower (and npm) version syntax?
...ke any subsequent patch-level changes on the 1.2.x tree, starting with 1.2.0, but less than 1.3.0, you could use:
"angular": "~1.2"
or:
"angular": "~1.2.0"
This also gets you the same results as using the .x syntax:
"angular": "1.2.x"
But, you can use the tilde/~ syntax to be even more spec...
Permutations in JavaScript?
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108
If you notice, the code actually splits the chars into an array prior to do any permutation, so...
Pandas index column title or name
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In [8]: df.index.name = 'foo'
In [9]: df.index.name
Out[9]: 'foo'
In [10]: df
Out[10]:
Column 1
foo
Apples 1
Oranges 2
Puppies 3
Ducks 4
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What is the difference between float and double?
...re calculated:
double has 52 mantissa bits + 1 hidden bit: log(253)÷log(10) = 15.95 digits
float has 23 mantissa bits + 1 hidden bit: log(224)÷log(10) = 7.22 digits
This precision loss could lead to greater truncation errors being accumulated when repeated calculations are done, e.g.
float a = 1...
Why does ++[[]][+[]]+[+[]] return the string “10”?
This is valid and returns the string "10" in JavaScript ( more examples here ):
9 Answers
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Custom numeric format string to always display the sign
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301
Yes, you can.
There is conditional formatting. See Conditional formatting in MSDN
eg:
strin...
What is the difference between Ruby 1.8 and Ruby 1.9
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170
Sam Ruby has a cool slideshow that outline the differences.
In the interest of bringing this in...
Is MATLAB OOP slow or am I doing something wrong?
...are some typical results.
>> call_nops
Computer: PCWIN Release: 2009b
Calling each function/method 100000 times
nop() function: 0.02261 sec 0.23 usec per call
nop1-5() functions: 0.02182 sec 0.22 usec per call
nop() subfunction: 0.02244 sec 0....
How to get first and last day of previous month (with timestamp) in SQL Server
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select DATEADD(MONTH, DATEDIFF(MONTH, 0, GETDATE())-1, 0) --First day of previous month
select DATEADD(MONTH, DATEDIFF(MONTH, -1, GETDATE())-1, -1) --Last Day of previous month
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