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python pandas remove duplicate columns
...,False,True].
Pandas allows one to index using boolean values whereby it selects only the True values. Since we want to keep the unduplicated columns, we need the above boolean array to be flipped (ie [True, True, False] = ~[False,False,True])
Finally, df.loc[:,[True,True,False]] selects only the...
How do I expand a tuple into variadic template function's arguments?
...me U> void my_func(T &&t, U &&u) {}
int main(int argc, char *argv[argc]) {
std::tuple<int, float> my_tuple;
std::apply([](auto &&... args) { my_func(args...); }, my_tuple);
return 0;
}
This work around is a simplified solution to the general problem of pa...
What's the recommended way to connect to MySQL from Go?
...l", store.user+":"+store.password+"@/"+store.database)
defer con.Close()
Select one row :
row := con.QueryRow("select mdpr, x, y, z from sometable where id=?", id)
cb := new(SomeThing)
err := row.Scan(&cb.Mdpr, &cb.X, &cb.Y, &cb.Z)
Select multiple rows and build an array with re...
Looping over arrays, printing both index and value
...="snoopy"
bar[bar]="nice"
bar[baz]="cool"
Issue with newlines or special chars
Unfortunely, there is at least one condition making this not work anymore: when variable do contain newline:
foo[17]=$'There is one\nnewline'
Command paste will merge line-by-line, so output will become wrong:
past...
CSS: background image on background color
I have panel which I colored blue if this panel is being selected (clicked on it). Additionally, I add a small sign ( .png image) to that panel, which indicates that the selected panel has been already selected before.
...
When should I use File.separator and when File.pathSeparator?
...e help of some code
separator: Platform dependent default name-separator character as String. For windows, it’s ‘\’ and for unix it’s ‘/’
separatorChar: Same as separator but it’s char
pathSeparator: Platform dependent variable for path-separator. For
example PATH or CLASSPATH variab...
What is meant by Resource Acquisition is Initialization (RAII)?
...s piece of code:
void fn(const std::string& str)
{
std::vector<char> vec;
for (auto c : str)
vec.push_back(c);
// do something
}
when you create a vector and you push elements to it, you don't care about allocating and deallocating such elements. The vector uses new ...
ValueError: The truth value of an array with more than one element is ambiguous. Use a.any() or a.al
...al code
mask = ((r["dt"] >= startdate) & (r["dt"] <= enddate))
selected = r[mask]
looks correct. However, if you do want and, then instead of a and b use (a-b).any() or (a-b).all().
share
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...
How does the SQL injection from the “Bobby Tables” XKCD comic work?
..., the parenthesis makes more sense with an INSERT. Thinking backwards, the SELECT would not run anyway as the Insert of the Little Bobby Tables in the table would have already dropped the table.
– ypercubeᵀᴹ
Jan 21 '13 at 21:41
...
JavaScript hashmap equivalent
...nctional solution is simple and fast.
The key function can be as simple as selecting right attributes of the object, e.g., a key, or a set of keys, which are already unique, a combination of keys, which are unique together, or as complex as using some cryptographic hashes like in DojoX encoding, or ...