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data.frame rows to a list
I have a data.frame which I would like to convert to a list by rows, meaning each row would correspond to its own list elements. In other words, I would like a list that is as long as the data.frame has rows.
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Where did the name `atoi` come from?
In the C language where did they come up with the name atoi for converting a string to an integer? The only thing I can think of is Array To Integer for an acronym but that doesn't really make sense.
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Why doesn't c++ have &&= or ||= for booleans?
...different value such as 2. When assigning that value to a bool, it will be converted to true as per the standard.
The only way to get an invalid value into a bool is by using reinterpret_cast on pointers:
int i = 2;
bool b = *reinterpret_cast<bool*>(&i);
b |= true; // MAY yield 3 (but do...
How do I get a value of datetime.today() in Python that is “timezone aware”?
...you are in UTC time to begin with. Always use timezone aware based on UTC. convert to local timezone on output when needed.
– MrE
Sep 13 '17 at 18:36
4
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How can I output the value of an enum class in C++11
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Unlike an unscoped enumeration, a scoped enumeration is not implicitly convertible to its integer value. You need to explicitly convert it to an integer using a cast:
std::cout << static_cast<std::underlying_type<A>::type>(a) << std::endl;
You may want to encapsulate ...
How to avoid warning when introducing NAs by coercion
...but I don't know how to avoid getting a warning when using as.numeric to convert a character vector.
4 Answers
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View.setPadding accepts only in px, is there anyway to setPadding in dp?
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This is the formula for Converting dp units to pixel units. You can use it anywhere
– Labeeb Panampullan
Jul 11 '11 at 7:42
2
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Reset select2 value and show placeholder
How do I set the placeholder on value reset by select2. In my example If locations or grade select boxes are clicked and my select2 has a value than the value of select2 should reset and show the default placeholder. This script is resetting the value but won't show the placeholder
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How to JSON serialize sets?
...ut then you would be giving up some other structure you might need (if you convert sets to a list, then you lose the ability to recover regular lists; if you convert sets to a dictionary using dict.fromkeys(s) then you lose the ability to recover dictionaries).
A more sophisticated solution is to b...
Why does “,,,” == Array(4) in Javascript?
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Because the right hand operand is converted to a string and the string representation of Array(4) is ,,,:
> Array(4).toString()
",,,"
If you use the array constructor function and pass a number, it sets the length of the array to that number. So you ...