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What does “coalgebra” mean in the context of programming?
...through all elements of A and b goes through all elements of B).
Disjoint union of two sets A and B is a set A | B which is a union of sets {(a, 1) : a in A} and {(b, 2) : b in B}. Essentially it is a set of all elements from both A and B, but with each of this elements 'marked' as belonging to eit...
'any' vs 'Object'
...d to accept multiple known types, a better approach is to declare it using union types, as in
function fc(param: string|number): void {}
Obviously, OO inheritance rules still apply, so if you want to accept instances of derived classes and treat them based on their base type, as in
interface IPe...
Read Excel File in Python
...ues for a given column
values = df['Arm_id'].values
#get a data frame with selected columns
FORMAT = ['Arm_id', 'DSPName', 'Pincode']
df_selected = df[FORMAT]
share
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Get the generated SQL statement from a SqlCommand object?
... }
sql.AppendLine(";");
sql.AppendLine("select 'Return Value' = convert(varchar, @return_value);");
foreach (SqlParameter sp in sc.Parameters)
{
if ((sp.Direction == ParameterDirection.InputOutput) || (sp.Directi...
How to split a file into equal parts, without breaking individual lines? [duplicate]
...
this is a way better answer than the selected one
– smatthewenglish
Apr 28 '16 at 11:41
...
Can I concatenate multiple MySQL rows into one field?
...
You can use GROUP_CONCAT:
SELECT person_id, GROUP_CONCAT(hobbies SEPARATOR ', ')
FROM peoples_hobbies
GROUP BY person_id;
As Ludwig stated in his comment, you can add the DISTINCT operator to avoid duplicates:
SELECT person_id, GROUP_CONCAT(DISTINCT ...
Is “argv[0] = name-of-executable” an accepted standard or just a common convention?
...ed to by argv[0] represents the program name; argv[0][0] shall be the null character if the program name is not available from the host environment.
So no, it's only the program name if that name is available. And it "represents" the program name, not necessarily is the program name. The section b...
How to change the color of an svg element?
...create a font out of the SVG using a service like https://icomoon.io/app/#/select or such. upload your SVG, click "generate font", include font files and css into your side and just use and style it like any other text. I always use it like this because it makes styling much easier.
EDIT: As mentio...
How do I use valgrind to find memory leaks?
...ok at the C code I wrote too:
#include <stdlib.h>
int main() {
char* string = malloc(5 * sizeof(char)); //LEAK: not freed!
return 0;
}
Well, there were 5 bytes lost. How did it happen? The error report just says
main and malloc. In a larger program, that would be seriously trouble...
Best practices for circular shift (rotate) operations in C++
...lude <stdint.h> // for uint32_t
#include <limits.h> // for CHAR_BIT
// #define NDEBUG
#include <assert.h>
static inline uint32_t rotl32 (uint32_t n, unsigned int c)
{
const unsigned int mask = (CHAR_BIT*sizeof(n) - 1); // assumes width is a power of 2.
// assert ( (c<...