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How do I replace NA values with zeros in an R dataframe?
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See my comment in @gsk3 answer. A simple example:
> m <- matrix(sample(c(NA, 1:10), 100, replace = TRUE), 10)
> d <- as.data.frame(m)
V1 V2 V3 V4 V5 V6 V7 V8 V9 V10
1 4 3 NA 3 7 6 6 10 6 5
2 9 8 9 5 10 NA 2 1 7 ...
Is MATLAB OOP slow or am I doing something wrong?
...ction/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 0.22 usec per call
@()[] anonymous function: 0.08461 sec 0.85 usec per call
nop(obj) metho...
Why am I getting a “401 Unauthorized” error in Maven?
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JohnJohn
6,54199 gold badges3535 silver badges9191 bronze badges
2
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Small Haskell program compiled with GHC into huge binary
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Let's see what's going on, try
$ du -hs A
13M A
$ file A
A: ELF 64-bit LSB executable, x86-64, version 1 (SYSV),
dynamically linked (uses shared libs), for GNU/Linux 2.6.27, not stripped
$ ldd A
linux-vdso.so.1 => (0x00007fff1b9ff000)
libXr...
What is the difference between Ruby 1.8 and Ruby 1.9
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Array.to_s Now Contains Punctuation
Ruby 1.9
irb(main):001:0> [1,2,3].to_s
=> "[1, 2, 3]"
Ruby 1.8.6
irb(main):001:0> [1,2,3].to_s
=> "123"
Action: Use .join instead
Colon No Longer Valid In When Statements
Ruby 1.9
irb(main):001:0> case 'a'; when /\w/: puts 'word'; end...
Extract first item of each sublist
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Using list comprehension:
>>> lst = [['a','b','c'], [1,2,3], ['x','y','z']]
>>> lst2 = [item[0] for item in lst]
>>> lst2
['a', 1, 'x']
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What does this square bracket and parenthesis bracket notation mean [first1,last1)?
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234
A bracket means that end of the range is inclusive -- it includes the element listed. A parenth...
how do I insert a column at a specific column index in pandas?
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388
see docs: http://pandas.pydata.org/pandas-docs/stable/generated/pandas.DataFrame.insert.html
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MDI CDockablePane使用总结 - C/C++ - 清泛网 - 专注C/C++及内核技术
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DockPane(&m_Panes[1]);// BOTTOM
DockPane(&m_Panes[0]);// LEFT
（3）第三种情况
if (!m_Panes[0].Create(_T("Pane 0"), this, CRect(0, 0, 200, 100), TRUE, 1000,
WS_CHILD | WS_VISIBLE | WS_CLIPSIBLINGS | WS_CLIPCHILDREN | CBRS_LEFT | CBRS_FLOAT_MULTI))
{return FALS...