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How to fix error with xml2-config not found when installing PHP from sources?
...
439
All you need to do instal install package libxml2-dev for example:
sudo apt-get install libxm...
Pandas: create two new columns in a dataframe with values calculated from a pre-existing column
... return x*2, x*3
...:
In [3]: df = DataFrame({'a': [1,2,3], 'b': [2,3,4]})
In [4]: df
Out[4]:
a b
0 1 2
1 2 3
2 3 4
In [5]: df["A1"], df["A2"] = zip(*df["a"].map(calculate))
In [6]: df
Out[6]:
a b A1 A2
0 1 2 2 3
1 2 3 4 6
2 3 4 6 9
...
jQuery map vs. each
...u can potentially waste a lot of memory.
For example:
var items = [1,2,3,4];
$.each(items, function() {
alert('this is ' + this);
});
var newItems = $.map(items, function(i) {
return i + 1;
});
// newItems is [2,3,4,5]
You can also use the map function to remove an item from an array. For...
Python integer division yields float
...Brandon E TaylorBrandon E Taylor
23.1k66 gold badges4343 silver badges6868 bronze badges
10
...
Pandas dataframe get first row of each group
...
248
>>> df.groupby('id').first()
value
id
1 first
2 first
3 first
4 ...
How to write multiple line string using Bash with variables?
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480
The syntax (<<<) and the command used (echo) is wrong.
Correct would be:
#!/bin/bas...
Single Line Nested For Loops
...hension (here (x,y)):
>>> [(x, y) for x in [1,2,3] for y in [3,1,4] if x != y]
[(1, 3), (1, 4), (2, 3), (2, 1), (2, 4), (3, 1), (3, 4)]
It's exactly the same as this nested for loop (and, as the tutorial says, note how the order of for and if are the same).
>>> combs = []
>&...
MySql: Tinyint (2) vs tinyint(1) - what is the difference?
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4 Answers
4
Active
...
while (1) vs. while(True) — Why is there a difference (in python 2 bytecode)?
...True is reassignable:
Python 2.7 (r27:82508, Jul 3 2010, 21:12:11)
[GCC 4.0.1 (Apple Inc. build 5493)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> True = 4
>>> True
4
In Python 3.x it truly becomes a keyword and a real constant:
Pyth...
How can I delete one element from an array by value
...
490
I think I've figured it out:
a = [3, 2, 4, 6, 3, 8]
a.delete(3)
#=> 3
a
#=> [2, 4, 6, 8...