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Performance of foreach, array_map with lambda and array_map with static function
...
}
return $result;
}
function useMapClosure($numbers) {
return array_map(function($number) {
return $number * 10;
}, $numbers);
}
function _tenTimes($number) {
return $number * 10;
}
function useMapNamed($numbers) {
return array_map('_tenTimes', $numbers);
}
foreach (array('F...
How To Change DataType of a DataColumn in a DataTable?
...newType)
{
using (DataColumn dc = new DataColumn(columnName + "_new", newType))
{
// Add the new column which has the new type, and move it to the ordinal of the old column
int ordinal = dt.Columns[columnName].Ordinal;
dt.Columns.Add(dc);
...
Why is Scala's immutable Set not covariant in its type?
... worth losing the use of that covariant type?
– oxbow_lakes
Mar 24 '09 at 22:00
23
The type signa...
get list from pandas dataframe column
...hon list. Alternatively you cast it with list(x).
import pandas as pd
data_dict = {'one': pd.Series([1, 2, 3], index=['a', 'b', 'c']),
'two': pd.Series([1, 2, 3, 4], index=['a', 'b', 'c', 'd'])}
df = pd.DataFrame(data_dict)
print(f"DataFrame:\n{df}\n")
print(f"column types:\n{df.dtyp...
Advantages to Using Private Static Methods
...y true. Let's assume that a Library has an instance field List<Book> _books to store it's books (not how you'd design a Library class probably but w/e), and it passes this list to findBook, and that static method calls books.Clear() or books.Reverse() and so on. If you give a static method acc...
Received an invalid column length from the bcp client for colid 6
...act 1 from it to get the value. After that it is used as the index of the _sortedColumnMappings ArrayList of the SqlBulkCopy instance not the index of the column mappings that were added to the SqlBulkCopy instance. One thing to note is that SqlBulkCopy will stop on the first error received so thi...
Determine if code is running as part of a unit test
...;/summary>
static class UnitTestDetector
{
private static bool _runningFromNUnit = false;
static UnitTestDetector()
{
foreach (Assembly assem in AppDomain.CurrentDomain.GetAssemblies())
{
// Can't do something like this as it will load the nUnit...
Python os.path.join on Windows
...is statement should be True
os.path.join(*os.path.dirname(os.path.abspath(__file__)).split(os.path.sep))==os.path.dirname(os.path.abspath(__file__))
But it is False on windows machines.
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i...
What is the difference between “ is None ” and “ ==None ”
...
class Foo:
def __eq__(self,other):
return True
foo=Foo()
print(foo==None)
# True
print(foo is None)
# False
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improve thi...
What does static_assert do, and what would you use it for?
Could you give an example where static_assert(...) ('C++11') would solve the problem in hand elegantly?
8 Answers
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