大约有 43,300 项符合查询结果（耗时：0.0496秒） [XML]
Finding quaternion representing the rotation from one vector to another
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117
Quaternion q;
vector a = crossproduct(v1, v2);
q.xyz = a;
q.w = sqrt((v1.Length ^ 2) * (v2.Len...
How can I apply a border only inside a table?
...is:
table {
border-collapse: collapse;
}
table td, table th {
border: 1px solid black;
}
table tr:first-child th {
border-top: 0;
}
table tr:last-child td {
border-bottom: 0;
}
table tr td:first-child,
table tr th:first-child {
border-left: 0;
}
table tr td:last-child,
table tr th:last-ch...
How do I read the first line of a file using cat?
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10 Answers
10
Active
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how to get the current working directory's absolute path from irb
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521
Dir.pwd seems to do the trick.
http://ruby-doc.org/core/Dir.html#method-c-pwd
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Random number from a range in a Bash Script
...er between 2000-65000 from a shell script. The problem is $RANDOM is a 15-bit number, so I'm stuck!
15 Answers
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How do I use the conditional operator (? :) in Ruby?
..., except for precedence issues. Both are expressions.
Examples:
puts (if 1 then 2 else 3 end) # => 2
puts 1 ? 2 : 3 # => 2
x = if 1 then 2 else 3 end
puts x # => 2
Note that in the first case parenthesis are required (otherwise Ruby is confused be...
How to retrieve absolute path given relative
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21 Answers
21
Active
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Remove all values within one list from another list? [duplicate]
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144
>>> a = range(1, 10)
>>> [x for x in a if x not in [2, 3, 7]]
[1, 4, 5, 6, 8...
How to convert all tables from MyISAM into InnoDB?
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174
<?php
// connect your database here first
//
// Actual code starts here
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How to serialize an Object into a list of URL query parameters?
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106
var str = "";
for (var key in obj) {
if (str != "") {
str += "&";
}
st...