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Select rows of a matrix that meet a condition
...me(). In that case the previous answers (using subset or m$three) will work, otherwise they will not.
To perform the operation on a matrix, you can define a column by name:
m[m[, "three"] == 11,]
Or by number:
m[m[,3] == 11,]
Note that if only one row matches, the result is an integer vector...
Read file line by line using ifstream in C++
...
First, make an ifstream:
#include <fstream>
std::ifstream infile("thefile.txt");
The two standard methods are:
Assume that every line consists of two numbers and read token by token:
int a, b;
while (infile >> a >...
How can I obtain an 'unbalanced' grid of ggplots?
...ot figures in a grid to achieve a multi-panel figure by using something like:
4 Answers
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How to change checkbox's border style in CSS?
How can I change checkbox (input) border's style? I've put border:1px solid #1e5180 upon it, but in FireFox 3.5, nothing happens!
...
Difference between single and double quotes in Bash
...t interpolate anything, but double quotes will. For example: variables, backticks, certain \ escapes, etc.
Example:
$ echo "$(echo "upg")"
upg
$ echo '$(echo "upg")'
$(echo "upg")
The Bash manual has this to say:
3.1.2.2 Single Quotes
Enclosing characters in single quotes (') preserves...
How to convert a NumPy array to PIL image applying matplotlib colormap
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Peter Mortensen
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answered Jun 10 '12 at 8:55
fraxelfraxel
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Difference in make_shared and normal shared_ptr in C++
Many google and stackoverflow posts are there on this, but I am not able to understand why make_shared is more efficient than directly using shared_ptr .
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Parse rfc3339 date strings in Python? [duplicate]
...eutil.parser.parse will attempt to guess the format of your string, if you know the exact format in advance then you can use datetime.strptime which you supply a format string to (see Brent Washburne's answer).
from dateutil.parser import parse
a = "2012-10-09T19:00:55Z"
b = parse(a)
print(b.wee...
程序员用数据思维教你如何追女生 - 杂谈 - 清泛网 - 专注C/C++及内核技术
...到底会不会喜欢你，会不会和你在一起的人。你会说，我K，这不就是她本人么？！错，这个人很有可能是每天都跟她在一起的闺蜜，或者是她妈。
（2）涉众的利益，涉众的意思，就是在你的追求计划中可能会产生作用的人，...
Why does Node.js' fs.readFile() return a buffer instead of string?
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Tomáš Zato - Reinstate Monica
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answered Jun 23 '11 at 15:53
davindavin
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