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How do I replace NA values with zeros in an R dataframe?
...nt 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 2
3 1 1 6 3 6 NA 1 4 1 6
4 NA 4 NA 7 10 2 NA 4 1...
What do hjust and vjust do when making a plot using ggplot?
...
The value of hjust and vjust are only defined between 0 and 1:
0 means left-justified
1 means right-justified
Source: ggplot2, Hadley Wickham, page 196
(Yes, I know that in most cases you can use it beyond this range, but don't expect it to behave in any specific way. This...
How do you match only valid roman numerals with a regular expression?
...
330
You can use the following regex for this:
^M{0,4}(CM|CD|D?C{0,3})(XC|XL|L?X{0,3})(IX|IV|V?I{0,3...
汇编常用寄存器及指令基础总结 - C/C++ - 清泛网 - 专注C/C++及内核技术
汇编常用寄存器及指令基础总结8086汇编常用寄存器数据寄存器AH&AL=AX：累加寄存器，常用于运算BH&BL=BX：基址寄存器，常用于地址索引CH&CL=CX：计数寄存器，常用于计数DH...8086汇编常用寄存器
数据寄存器
AH&AL=AX：累加寄存器，...
How can I profile C++ code running on Linux?
...
1440
If your goal is to use a profiler, use one of the suggested ones.
However, if you're in a hurry...
What Process is using all of my disk IO
...
You're looking for iotop (assuming you've got kernel >2.6.20 and Python 2.5). Failing that, you're looking into hooking into the filesystem. I recommend the former.
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Version number comparison in Python
... cmp -like function which compares two version numbers and returns -1 , 0 , or 1 based on their compared valuses.
17 A...
Remove empty elements from an array in Javascript
...xample, if you want to remove null or undefined values:
var array = [0, 1, null, 2, "", 3, undefined, 3,,,,,, 4,, 4,, 5,, 6,,,,];
var filtered = array.filter(function (el) {
return el != null;
});
console.log(filtered);
It will depend on what you consider to be "empty" for exa...
What does this square bracket and parenthesis bracket notation mean [first1,last1)?
...rst1 (and includes it), but ends just before last1.
Assuming integers:
(0, 5) = 1, 2, 3, 4
(0, 5] = 1, 2, 3, 4, 5
[0, 5) = 0, 1, 2, 3, 4
[0, 5] = 0, 1, 2, 3, 4, 5
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How to find the installed pandas version
...ersion__:
In [76]: import pandas as pd
In [77]: pd.__version__
Out[77]: '0.12.0-933-g281dc4e'
Pandas also provides a utility function, pd.show_versions(), which reports the version of its dependencies as well:
In [53]: pd.show_versions(as_json=False)
INSTALLED VERSIONS
------------------
commi...