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How do the PHP equality (== double equals) and identity (=== triple equals) comparison operators dif
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640
Difference between == and ===
The difference between the loosely == equal operator and the stri...
Gem::LoadError for mysql2 gem, but it's already in Gemfile
... with rails 4.1.5) try using this version of mysql2:
gem 'mysql2', '~> 0.3.18'
Apparently mysql2 isn't still compatible with newer version of rails because rails 4.2.4 is pretty new as the time of answering this question by me 8 September 2015 so use the above line in your Gem file and run:
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Given an array of numbers, return array of products of all other numbers (no division)
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260
An explanation of polygenelubricants method is:
The trick is to construct the arrays (in the c...
Expand a random range from 1–5 to 1–7
...2, 3 },
{ 4, 5, 6, 7, 1 },
{ 2, 3, 4, 5, 6 },
{ 7, 0, 0, 0, 0 }
};
int result = 0;
while (result == 0)
{
int i = rand5();
int j = rand5();
result = vals[i-1][j-1];
}
return result;
}
How does it work? Think of it like this: i...
Regular expression for a hexadecimal number?
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How about the following?
0[xX][0-9a-fA-F]+
Matches expression starting with a 0, following by either a lower or uppercase x, followed by one or more characters in the ranges 0-9, or a-f, or A-F
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Path to Powershell.exe (v 2.0)
Where is the Powershell (version 2.0) located? What is the path to Powershell.exe? I have Windows Server 2008 and Powershell installed. When I look at this folder:
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Assign pandas dataframe column dtypes
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Since 0.17, you have to use the explicit conversions:
pd.to_datetime, pd.to_timedelta and pd.to_numeric
(As mentioned below, no more "magic", convert_objects has been deprecated in 0.17)
df = pd.DataFrame({'x': {0: 'a', 1: 'b'}...
How to make rounded percentages add up to 100%
...ff = target - _.reduce(l, function(acc, x) { return acc + Math.round(x) }, 0);
return _.chain(l).
sortBy(function(x) { return Math.round(x) - x }).
map(function(x, i) { return Math.round(x) + (off > i) - (i >= (l.length + off)) }).
value();
}
foo([13.62...
Label points in geom_point
...our="green", label=Name))+
geom_point() +geom_text(aes(label=Name),hjust=0, vjust=0)
EDIT: Label only values above a certain threshold:
ggplot(nba, aes(x= MIN, y= PTS, colour="green", label=Name))+
geom_point() +
geom_text(aes(label=ifelse(PTS>24,as.character(Name),'')),hjust=0,vjust...
Python division
I was trying to normalize a set of numbers from -100 to 0 to a range of 10-100 and was having problems only to notice that even with no variables at all, this does not evaluate the way I would expect it to:
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