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What is the proper #include for the function 'sleep()'?
... On UNIX, Sleep is actually usleep and it takes microseconds (milliseconds*1000) instead of seconds.
– Agostino
Feb 6 '17 at 14:59
6
...
Linear Regression and group by in R
...048 0.13515755 0.1980687 0.8479318
# 3 NY (Intercept) -0.35135766 0.60100314 -0.5846187 0.5749166
# 4 NY year 0.09385309 0.09686043 0.9689519 0.3609470
fitted_models %>% glance(model)
# Source: local data frame [2 x 12]
# Groups: state [2]
#
# state r.squared adj.r.squared...
calculating the difference in months between two dates
...se? so if you are referring to particular, known months, then my method is 100% accurate and you're would be an approximation, however, if you are referring to a month in general, you're approximation would be a better idea, and mine would just be a bad idea (it isn't made for that and there would b...
Why does parseInt yield NaN with Array#map?
...Int's radix parameter.
If you're using underscore you can do:
['10','1','100'].map(_.partial(parseInt, _, 10))
Or without underscore:
['10','1','100'].map(function(x) { return parseInt(x, 10); });
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...
Programmatically set height on LayoutParams as density-independent pixels
...
/**
* Get conversion rate from dp into px.<br>
* E.g. to convert 100dp: px = (int) (100 * convRate);
* @param context e.g. activity
* @return conversion rate
*/
public static float convRateDpToPx(Context context) {
return context.getResources().getDisplayMetrics().densityDpi / 160f;...
How are feature_importances in RandomForestClassifier determined?
...-(0+3*0.444)) + (3*0.444-(0+0)))
print("petal width (cm)",(150* 0.667 - (0+100*0.5)) +(100*0.5-(54*0.168+46*0.043))+(6*0.444 -(0+3*0.444)) + (48*0.041-(0+0)))
We get feature_importance: np.array([0,1.332,6.418,92.30]).
After normalized, we can get array ([0., 0.01331334, 0.06414793, 0.92253873]),t...
Difference between abstraction and encapsulation?
...
+100
Most answers here focus on OOP but encapsulation begins much earlier:
Every function is an encapsulation; in pseudocode:
point x ...
Avoid trailing zeroes in printf()
..., it won't cause a problem (at least for that value) since the resultant 0.10000000000000000555 will be 0.1 when stripped back. The problem may come if you have a value slightly under such as if the closest representation of 42.1 was 42.099999999314159. If you really wanted to handle that, then you'...
Difference between `constexpr` and `const`
...ds. For example.
class test
{
int x;
void function1()
{
x=100; // OK.
}
void function2() const
{
x=100; // ERROR. The const methods can't change the values of object fields.
}
};
A constexpr is a different concept. It marks a function (member or non-member) as t...
How to define two fields “unique” as couple
... "Journal")
volume_number = models.CharField('Volume Number', max_length=100)
comments = models.TextField('Comments', max_length=4000, blank=True)
class Meta:
unique_together = ('journal_id', 'volume_number',)
sh...