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How to write Unicode characters to the console?
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203
It's likely that your output encoding is set to ASCII. Try using this before sending output:
C...
How can I parse a string with a comma thousand separator to a number?
I have 2,299.00 as a string and I am trying to parse it to a number. I tried using parseFloat , which results in 2. I guess the comma is the problem, but how would I solve this issue the right way? Just remove the comma?
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add column to mysql table if it does not exist
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Note that INFORMATION_SCHEMA isn't supported in MySQL prior to 5.0. Nor are stored procedures supported prior to 5.0, so if you need to support MySQL 4.1, this solution isn't good.
One solution used by frameworks that use database migrations is to record in your database a revision numbe...
Visual Studio Editor does not underline errors anymore
My Visual Studio (2008) Editor has stopped to underline Errors (this nifty wavy red lines). I can't really tell when, but it can be related to the installation of .Net Framework 3.5 SP 1 or the MVC Beta (which I guess is unlikely). Furthermore have I installed and uninstalled both CodeRush and Resha...
How to use Elasticsearch with MongoDB?
...to index MongoDB for use in a NodeJS, Express app on a fresh EC2 Ubuntu 14.04 instance.
Make sure everything is up to date.
sudo apt-get update
Install NodeJS.
sudo apt-get install nodejs
sudo apt-get install npm
Install MongoDB - These steps are straight from MongoDB docs.
Choose whatever ve...
Making an iframe responsive
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108
I present to you The Incredible Singing Cat solution =)
.wrapper {
position: relative;
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How can I rename a field for all documents in MongoDB?
Assuming I have a collection in MongoDB with 5000 records, each containing something similar to:
7 Answers
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LINQ - Left Join, Group By, and Count
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answered Mar 29 '09 at 22:28
Mehrdad AfshariMehrdad Afshari
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Pure virtual destructor in C++
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220
Yes. You also need to implement the destructor:
class A {
public:
virtual ~A() = 0;
};
inl...
Pandas conditional creation of a series/dataframe column
...here(df['Set']=='Z', 'green', 'red')
print(df)
yields
Set Type color
0 Z A green
1 Z B green
2 X B red
3 Y C red
If you have more than two conditions then use np.select. For example, if you want color to be
yellow when (df['Set'] == 'Z') & (df['Type'] == ...