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How to add leading zeros?
...Which one is best depends upon what other formatting you want to do.
The example from the question is quite easy since all the values have the same number of digits to begin with, so let's try a harder example of making powers of 10 width 8 too.
anim <- 25499:25504
x <- 10 ^ (0:5)
paste ...
LINQ Using Max() to select a single row
...Queryable returned from NHibernate and I need to select the row with the maximum value(s) in a couple of fields.
6 Answers...
How to maintain aspect ratio using HTML IMG tag
...ht and width attribute to 64. I need to show any image resolution (e.g. 256x256, 1024x768, 500x400, 205x246, etc.) as 64x64. But by setting the height and width attributes of an img tag to 64, it's not maintaining the aspect ratio, so the image looks distorted.
...
Pandas percentage of total with groupby
... and divide by sum
state_pcts = state_office.groupby(level=0).apply(lambda x:
100 * x / float(x.sum()))
Returns:
sales
state office_id
AZ 2 16.981365
4 19.250033
6 63.768601
...
Can I implement an autonomous `self` member type in C++?
...of Foo:
template <typename...Ts>
class Self;
template <typename X, typename...Ts>
class Self<X,Ts...> : public Ts...
{
protected:
typedef X self;
};
#define WITH_SELF(X) X : public Self<X>
#define WITH_SELF_DERIVED(X,...) X : public Self<X,__VA_ARGS__>
class WIT...
What would a “frozen dict” be?
...sh = hash_
return self._hash
It should work great:
>>> x = FrozenDict(a=1, b=2)
>>> y = FrozenDict(a=1, b=2)
>>> x is y
False
>>> x == y
True
>>> x == {'a': 1, 'b': 2}
True
>>> d = {x: 'foo'}
>>> d[y]
'foo'
...
Find first element in a sequence that matches a predicate
...
To find first element in a sequence seq that matches a predicate:
next(x for x in seq if predicate(x))
Or (itertools.ifilter on Python 2):
next(filter(predicate, seq))
It raises StopIteration if there is none.
To return None if there is no such element:
next((x for x in seq if predic...
What is the purpose of setting a key in data.table?
...ta.table and there are many functions which require me to set a key (e.g. X[Y] ). As such, I wish to understand what a key does in order to properly set keys in my data tables.
...
Is multiplication and division using shift operators in C actually faster?
Multiplication and division can be achieved using bit operators, for example
19 Answers
...
Split function equivalent in T-SQL?
... set @iStart = 1
while 1=1
begin
set @iPos = charindex( @cDelimiter, @sString, @iStart )
if @iPos = 0
set @iPos = len( @sString )+1
if @iPos - @iStart > 0
insert into @tParts
values ( substring( @sString, @iStart...