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How to reset index in a pandas dataframe? [duplicate]
...is faster:
df = pd.DataFrame({'a':[8,7], 'c':[2,4]}, index=[7,8])
df = pd.concat([df]*10000)
print (df.head())
In [298]: %timeit df1 = df.reset_index(drop=True)
The slowest run took 7.26 times longer than the fastest. This could mean that an intermediate result is being cached.
10000 loops, best o...
How to read the content of a file to a string in C?
... to interpret it) to open a file in C and read its contents into a string (char*, char[], whatever)?
11 Answers
...
sizeof single struct member in C
...->member)
and use it like this:
typedef struct
{
float calc;
char text[255];
int used;
} Parent;
typedef struct
{
char flag;
char text[member_size(Parent, text)];
int used;
} Child;
I'm actually a bit surprised that sizeof((type *)0)->member) is even allowed as a ...
How can I get a file's size in C? [duplicate]
...ring, which I allocate using malloc() . Just writing malloc(10000*sizeof(char)); is IMHO a bad idea.
8 Answers
...
Random String Generator Returning Same String [duplicate]
...g. My goal is to be able to run this twice and generate two distinct four character random strings. However, it just generates one four character random string twice.
...
Code Golf: Collatz Conjecture
...
x86 assembly, 1337 characters
;
; To assemble and link this program, just run:
;
; >> $ nasm -f elf collatz.asm && gcc -o collatz collatz.o
;
; You can then enjoy its output by passing a number to it on the command line:
;
; >...
Natural Sort Order in C#
...t as the comparison function in your IComparer:
[DllImport("shlwapi.dll", CharSet = CharSet.Unicode)]
private static extern int StrCmpLogicalW(string psz1, string psz2);
Michael Kaplan has some examples of how this function works here, and the changes that were made for Vista to make it work more...
std::string formatting like sprintf
...'ll have to do it first in a c-string, then copy it into a std::string:
char buff[100];
snprintf(buff, sizeof(buff), "%s", "Hello");
std::string buffAsStdStr = buff;
But I'm not sure why you wouldn't just use a string stream? I'm assuming you have specific reasons to not just do this:
st...
Static constant string (class member)
... requirement for using a STL string, you might as well just define a const char*. (less overhead)
– KSchmidt
Oct 14 '09 at 2:23
51
...
Group query results by month and year in postgresql
...
select to_char(date,'Mon') as mon,
extract(year from date) as yyyy,
sum("Sales") as "Sales"
from yourtable
group by 1,2
At the request of Radu, I will explain that query:
to_char(date,'Mon') as mon, : converts the "dat...