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Convert a row of a data frame to vector
...u have to be careful if your row contains a factor. Here is an example:
df_1 = data.frame(V1 = factor(11:15),
V2 = 21:25)
df_1[1,] %>% as.numeric() # you expect 11 21 but it returns
[1] 1 21
Here is another example (by default data.frame() converts characters to factors)
d...
How can I include a YAML file inside another?
...nstructor.
import yaml
import os
class Loader(yaml.SafeLoader):
def __init__(self, stream):
self._root = os.path.split(stream.name)[0]
super(Loader, self).__init__(stream)
def include(self, node):
filename = os.path.join(self._root, self.construct_scalar(node))...
How do I make a textbox that only accepts numbers?
... with this two event handlers on a standard TextBox:
private void textBox1_KeyPress(object sender, KeyPressEventArgs e)
{
if (!char.IsControl(e.KeyChar) && !char.IsDigit(e.KeyChar) &&
(e.KeyChar != '.'))
{
e.Handled = true;
}
// only allow one de...
MongoDB副本集详解 优于以往的主从模式 - 大数据 & AI - 清泛网 - 专注C/C++及内核技术
...ngodb.org/downloads
实验环境使用的Mongodb版本为mongodb-linux-x86_64-2.6.0
由三台虚拟机搭建，配置为单核,1G内存。实验环境如下:
MongoDB的副本集不同于以往的主从模式。
在集群Master故障的时候，副本集可以自动投票，选举出新的Maste...
What does the variable $this mean in PHP?
...P.html
Example:
<?php
class Person {
public $name;
function __construct( $name ) {
$this->name = $name;
}
};
$jack = new Person('Jack');
echo $jack->name;
This stores the 'Jack' string as a property of the object created.
...
Change SVN repository URL
...URL to non-SSH or vice versa, for example: svn switch --relocate svn+ssh://_svn_server_/_svn_project_/_svn_branch_ svn://_svn_server_/_svn_project_/_svn_branch_. The last is especially helpful if you do automated checkout as svn+ssh on several nodes using Jenkins API and some of them (Windows nodes)...
Where do “pure virtual function call” crashes come from?
...dler. You do this by providing your own function with this signature:
int __cdecl _purecall(void)
and linking it before you link the runtime library. This gives YOU control of what happens when a purecall is detected. Once you have control you can do something more useful than the standard handle...
Writing unit tests in Python: How do I start? [closed]
...est):
import unittest
class LearningCase(unittest.TestCase):
def test_starting_out(self):
self.assertEqual(1, 1)
def main():
unittest.main()
if __name__ == "__main__":
main()
Example 2 (pytest):
def test_starting_out():
assert 1 == 1
Assuming that both files are name...
How do I partially update an object in MongoDB so the new object will overlay / merge with the exist
...e data then?
You know you can do the following:
db.collection.update( { _id:...} , { $set: someObjectWithNewData }
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Conditional compilation and framework targets
...rgetFrameworkVersion.Replace('v', '')) >= 2.0 ">$(DefineConstants)NET_20_OR_GREATER, </DefineConstants>
<DefineConstants Condition=" $(TargetFrameworkVersion.Replace('v', '')) >= 3.5 ">$(DefineConstants)NET_35_OR_GREATER</DefineConstants>
<DefineConstants Condition=...