大约有 3,517 项符合查询结果（耗时：0.0187秒） [XML]
Filter dict to contain only certain keys?
...h a dictionary of 26 items (timeit(..., setup="d = {chr(x+97):x+1 for x in range(26)}")), depending on how many items are being filtered out (filtering out consonant keys is faster than filtering out vowel keys because you're looking up fewer items). The difference in performance may very well becom...
How do I reverse a C++ vector?
...ector>
#include <iostream>
template<class InIt>
void print_range(InIt first, InIt last, char const* delim = "\n"){
--last;
for(; first != last; ++first){
std::cout << *first << delim;
}
std::cout << *first;
}
int main(){
int a[] = { 1, 2, 3, 4, 5 };
...
Two-dimensional array in Swift
...{
assert(indexIsValid(row: row, column: column), "Index out of range")
return grid[(row * columns) + column]
}
set {
assert(indexIsValid(row: row, column: column), "Index out of range")
grid[(row * columns) + column] = newValue
...
PHP: Return all dates between two dates in an array [duplicate]
...
function createDateRangeArray($strDateFrom,$strDateTo)
{
// takes two dates formatted as YYYY-MM-DD and creates an
// inclusive array of the dates between the from and to dates.
// could test validity of dates here but I'm already ...
size_t vs. uintptr_t
... ptrdiff_t and intptr_t - wouldn't both of these be able to store the same range of values on almost any platform? Why have both signed and unsigned pointer-sized integer types, particularly if ptrdiff_t already serves the purpose of a signed pointer-sized integer type.
– Chris...
How can I filter lines on load in Pandas read_csv function?
...lues? E.g.: constant1 > chunk['field'] > constant2. Or can I use 'in range' ?
– weefwefwqg3
Feb 19 '17 at 6:32
1
...
Inline labels in Matplotlib
...atrix
pop = np.zeros((Nlines, N, N), dtype=np.float)
for l in range(Nlines):
# get xy data and scale it to the NxN squares
xy = axis.lines[l].get_xydata()
xy = (xy - [xmin,ymin]) / ([xmax-xmin, ymax-ymin]) * N
xy = xy.astype(np.int32)
# mask stuff...
Stripping everything but alphanumeric chars from a string in Python
...the characters you wish to delete:
delchars = ''.join(c for c in map(chr, range(256)) if not c.isalnum())
(2) Whenever you want to scrunch a string:
scrunched = s.translate(None, delchars)
The setup cost probably compares favourably with re.compile; the marginal cost is way lower:
C:\junk>...
How to read the output from git diff?
...p_fetch(int argc, const char **argv, ... It is in the format @@ from-file-range to-file-range @@ [header]. The from-file-range is in the form -<start line>,<number of lines>, and to-file-range is +<start line>,<number of lines>. Both start-line and number-of-lines refer to...
How to declare an array in Python?
...an list with the first 30 cells already filled.
So
f = []
for i in range(30):
f.append(0)
An example to where this could be used is in Fibonacci sequence.
See problem 2 in Project Euler
share
|
...