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How to filter Pandas dataframe using 'in' and 'not in' like in SQL
...where)
As a worked example:
import pandas as pd
>>> df
country
0 US
1 UK
2 Germany
3 China
>>> countries_to_keep
['UK', 'China']
>>> df.country.isin(countries_to_keep)
0 False
1 True
2 False
3 True
Name: country, dtype: bool
>>>...
How to write the Fibonacci Sequence?
...rning the Fibonacci numbers between a range (ie. startNumber 1, endNumber 20 should = only those numbers between 1 & 20), I have written for the program to display all Fibonacci numbers between a range (ie. startNumber 1, endNumber 20 displays = First 20 Fibonacci numbers). I thought I had a sure-fi...
Which is faster: while(1) or while(2)?
...arying levels of optimization:
int main(void) {
while(1) {}
return 0;
}
int main(void) {
while(2) {}
return 0;
}
Even with no optimizations (-O0), the generated assembly was identical for both programs. Therefore, there is no speed difference between the two loops.
For reference, ...
Building executable jar with maven?
...at the answer given in the question you mentioned is just wrong (UPDATE - 20101106: someone fixed it, this answer refers to the version preceding the edit) and this explains, at least partially, why you run into troubles.
It generates two jar files in logmanager/target: logmanager-0.1.0.jar, and l...
Drawing a dot on HTML5 canvas [duplicate]
...d it. Just draw a rectangle with a width and height of one:
ctx.fillRect(10,10,1,1); // fill in the pixel at (10,10)
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RegEx for Javascript to allow only alphanumeric
...
/^[a-z0-9]+$/i
^ Start of string
[a-z0-9] a or b or c or ... z or 0 or 1 or ... 9
+ one or more times (change to * to allow empty string)
$ end of string
/i case-insensitive
Update (supporting ...
Reverse Range in Swift
...:to:by:) is similar but excludes the last value
for i in stride(from:5,to:0,by:-1) { print(i) } // 5 4 3 2 1
Update For latest Swift 2
First of all, protocol extensions change how reverse is used:
for i in (1...5).reverse() { print(i) } // 5 4 3 2 1
Stride has been reworked in Xcode 7 Beta 6. ...
What does `void 0` mean? [duplicate]
...
1024
What does void 0 mean?
void[MDN] is a prefix keyword that takes one argument and always retur...
What is a NullPointerException, and how do I fix it?
...d to be a poor practice.
– Tiny
Feb 27 '16 at 2:05
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