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What are the differences between numpy arrays and matrices? Which one should I use?
...
Or just np.linalg.matrix_power(mat, n)
– Eric
Feb 28 '17 at 11:16
I...
Sequence contains no matching element
...'d expect it's this line that's throwing the exception:
var documentRow = _dsACL.Documents.First(o => o.ID == id)
First() will throw an exception if it can't find any matching elements. Given that you're testing for null immediately afterwards, it sounds like you want FirstOrDefault(), which r...
UITextView that expands to text using auto layout
...nstraint for UITextView's height, and I saved it in an instance variable.
_descriptionHeightConstraint = [NSLayoutConstraint constraintWithItem:_descriptionTextView
attribute:NSLayoutAttributeHeight
relatedBy:NSLayoutRelationEqual
...
What is the difference between _tmain() and main() in C++?
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_tmain does not exist in C++. main does.
_tmain is a Microsoft extension.
main is, according to the C++ standard, the program's entry point.
It has one of these two signatures:
int main();
int main(int argc, char* argv[]);...
Recursive file search using PowerShell
...above mean is... ls -r -ea silentlycontinue -fo -inc "filename.txt" | % { $_.fullname }
– Andrew
Nov 4 '17 at 7:34
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check if variable is dataframe
...rame
Yes: isinstance(x, pd.DataFrame)
And don't even think about
if obj.__class__.__name__ = 'DataFrame':
expect_problems_some_day()
isinstance handles inheritance (see What are the differences between type() and isinstance()?). For example, it will tell you if a variable is a string (eithe...
Python unittests in Jenkins?
...ittest.TestCase):
@unittest.skip("demonstrating skipping")
def test_skipped(self):
self.fail("shouldn't happen")
def test_pass(self):
self.assertEqual(10, 7 + 3)
def test_fail(self):
self.assertEqual(11, 7 + 3)
JUnit with pytest
run the tests with:
py.te...
Do try/catch blocks hurt performance when exceptions are not thrown?
...TryCatch() cil managed
{
// Code size 32 (0x20)
.maxstack 8
IL_0000: nop
IL_0001: ldstr "SIN(1) = {0} - No Try/Catch"
IL_0006: ldc.r8 1.
IL_000f: call float64 [mscorlib]System.Math::Sin(float64)
IL_0014: box [mscorlib]System.Double
IL_0019: call ...
How can jQuery deferred be used?
...he new Deferred object and the attached methods .when , .Deferred and ._Deferred .
11 Answers
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Removing all non-numeric characters from string in Python
...n Python2, and both strings and bytes in Python3:
# python <3.0
def only_numerics(seq):
return filter(type(seq).isdigit, seq)
# python ≥3.0
def only_numerics(seq):
seq_type= type(seq)
return seq_type().join(filter(seq_type.isdigit, seq))
...