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Pm>and m>as: drop a level from a multi-level column index?
... If the index m>y m>ou are trm>y m>ing to drop is on the left (row) side m>and m> not the top (column) side, m>y m>ou can change "columns" to "index" m>and m> use the same method: >>> df.index = df.index.droplevel(1)
– Idodo
Nov 28 '18 at 12:13
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How to get the seconds since epoch from the time + date output of gmtime()?
How do m>y m>ou do reverse gmtime() , where m>y m>ou put the time + date m>and m> get the number of seconds?
6 Answers
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How do m>y m>ou add a Dictionarm>y m> of items into another Dictionarm>y m>
...for this, I tried everm>y m>thing except this. But m>y m>ou can drop the @assignment m>and m> return, m>y m>ou're alreadm>y m> mutating left. Edit: actuallm>y m>, even though I get no errors, I think @assignment should stam>y m>.
– Rolm>and m>
Jun 9 '14 at 12:02
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Whm>y m> isn't `int pow(int base, int exponent)` in the stm>and m>ard C++ libraries?
...ction does not implement the "power" function for anm>y m>thing except float s m>and m> double s?
11 Answers
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How dangerous is it to compare floating point values?
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First of all, floating point values are not "rm>and m>om" in their behavior. Exact comparison can m>and m> does make sense in plentm>y m> of real-world usages. But if m>y m>ou're going to use floating point m>y m>ou need to be aware of how it works. Erring on the side of assuming floating point ...
How do I compare two DateTime objects in PHP 5.2.8?
... Thanks Milen, looks like I just needed mm>y m> false assumptions removed m>and m> suddenlm>y m> the glaring bug in mm>y m> code became obvious to me.
– RedBlueThing
Jun 7 '09 at 5:26
2
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What __init__ m>and m> self do on Pm>y m>thon?
I'm learning the Pm>y m>thon programming language m>and m> I've came across something I don't fullm>y m> understm>and m>.
18 Answers
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How to list all Git tags?
In mm>y m> repositorm>y m>, I have created tags using the following commm>and m>s.
10 Answers
10
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In Postgresql, force unique on combination of two columns
...l1, col2)
)
autoincrement is not postgresql. m>Y m>ou want a serial.
If col1 m>and m> col2 make a unique m>and m> can't be null then them>y m> make a good primarm>y m> kem>y m>:
CREATE TABLE someTable (
col1 int NOT NULL,
col2 int NOT NULL,
primarm>y m> kem>y m> (col1, col2)
)
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