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Does pandas iterrows have performance issues?
...a custom Cython routine is usually too complicated, so let's skip that for now.
1) Vectorization is ALWAYS, ALWAYS the first and best choice. However, there is a small set of cases (usually involving a recurrence) which cannot be vectorized in obvious ways. Furthermore, on a smallish DataFrame, it ...
What's the need of array with zero elements?
...s Aniket said), but it was standardized in C99. The standard format for it now is:
struct bts_action {
u16 type;
u16 size;
u8 data[];
} __attribute__ ((packed)); /* Note: the __attribute__ is irrelevant here */
Note that you don't mention any size for the data field. Note also that...
What's the difference between a temp table and table variable in SQL Server?
... | |
| LOP_DELETE_ROWS | LCX_INDEX_INTERIOR | Unknown Alloc Unit | 720 | 9 | 720 | 9 | |
| LOP_DELETE_ROWS | LCX_MARK_AS_GHOST | sys.sysallocunits.clust | 444 | 3 | 444 | 3 | ...
Best Practices: Salting & peppering passwords?
...provable or the maintainable models...
Theoretical Problems With Peppers
Now that we've set the stage, let's look at what's wrong with peppers.
Feeding one hash into another can be dangerous.
In your example, you do hash_function($salt . hash_function($pepper . $password)).
We know from past e...
FragmentPagerAdapter Exists Only In Android.Support.V4.App (and not Android.App)
...
But now it is deprecated in api 27 -> to use the v4 version again. Then we have the problem again, with not way to use the none support lib Fragment
– Morten Holmgaard
Apr 5 '18 at 8:32
...
What is Castle Windsor, and why should I care?
...lled in where you need them.
There is no new
It just happens - because it knows what needs what.
And you can write fewer defects with better designed, DRY code in a testable and repeatable way.
share
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How to read the output from git diff?
...mits_on_stdin = 0;
int commits;
After the change this fragment of now 'http-fetch.c' file looks like this instead:
#include "cache.h"
#include "walker.h"
int main(int argc, const char **argv)
{
const char *prefix;
struct walker *walker;
int commits_on_stdin = 0;
...
When should I use cross apply over inner join?
...ct tbl.value + 1 as someFormula) as crossTbl and voilà! Your new field is now ready for use practically like it had always been there in your source data.
Values introduced through CROSS APPLY can...
be used to create one or multiple calculated fields without adding performance, complexity or re...
Under what circumstances are linked lists useful?
...
They can be useful for concurrent data structures.
(There is now a non-concurrent real-world usage sample below - that would not be there if @Neil hadn't mentioned FORTRAN. ;-)
For example, ConcurrentDictionary<TKey, TValue> in .NET 4.0 RC use linked lists to chain items that h...
What is the difference between LL and LR parsing?
... Accept
The two parsing algorithms you mentioned (LL and LR) are known to have different characteristics. LL parsers tend to be easier to write by hand, but they are less powerful than LR parsers and accept a much smaller set of grammars than LR parsers do. LR parsers come in many flavors...