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Modifying a subset of rows in a pandas dataframe
...fy this DataFrame (or create a copy) so that B is always NaN whenever A is 0. How would I achieve that?
5 Answers
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New Array from Index Range Swift
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This works for me:
var test = [1, 2, 3]
var n = 2
var test2 = test[0..<n]
Your issue could be with how you're declaring your array to begin with.
EDIT:
To fix your function, you have to cast your Slice to an array:
func aFunction(numbers: Array<Int>, position: Int) -> Array&...
Is object empty? [duplicate]
...n-zero value
// that that property is correct.
if (obj.length > 0) return false;
if (obj.length === 0) return true;
// If it isn't an object at this point
// it is empty, but it can't be anything *but* empty
// Is it empty? Depends on your application.
if (typeof...
UITableView - scroll to the top
...e top. But I cannot guarantee that the first object is going to be section 0, row 0. May be that my table view will start from section number 5.
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ERROR 2003 (HY000): Can't connect to MySQL server on '127.0.0.1' (111)
...abled):
run the command vim /etc/mysql/my.cnf
comment bind-address = 127.0.0.1 using the # symbol
restart your mysql server once.
Update
In Step 1, if you cannot find bind-address in the my.cnf file, look for it in /etc/mysql/mysql.conf.d/mysqld.cnf file.
Update in case of MySQL replication en...
Formatting a number with exactly two decimals in JavaScript
...ich rounds my numbers to two decimal places. But I get numbers like this: 10.8, 2.4, etc. These are not my idea of two decimal places so how I can improve the following?
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Can a class member function template be virtual?
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answered Mar 1 '10 at 8:52
sbisbi
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How to compare versions in Ruby?
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Gem::Version.new('0.4.1') > Gem::Version.new('0.10.1')
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How to draw a rounded Rectangle on HTML Canvas?
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50
The HTML5 canvas doesn't provide a method to draw a rectangle with rounded corners.
How about u...
How to check if a string is a valid hex color representation?
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/^#[0-9A-F]{6}$/i.test('#AABBCC')
To elaborate:
^ -> match beginning
# -> a hash
[0-9A-F] -> any integer from 0 to 9 and any letter from A to F
{6} -> the previous group appears exactly 6...