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How to detect if a function is called as constructor?
...nce.
Looking at the ECMAScript 3rd edition spec, the steps taken when new m>x m>() is called are essentially:
Create a new object
Assign its internal [[Prototype]] property to the prototype property of m>x m>
Call m>x m> as normal, passing it the new object as this
If the call to m>x m> returned an object, return it...
data.frame rows to a list
...
Like this:
m>x m>y.list <- split(m>x m>y.df, seq(nrow(m>x m>y.df)))
And if you want the rownames of m>x m>y.df to be the names of the output list, you can do:
m>x m>y.list <- setNames(split(m>x m>y.df, seq(nrow(m>x m>y.df))), rownames(m>x m>y.df))
...
Python matplotlib multiple bars
...e red can be seen only.
How can I plot the multiple bars with dates on the m>x m>-am>x m>es?
5 Answers
...
Converting int to bytes in Python 3
...es on an iterable instead of a single integer:
>>> bytes([3])
b'\m>x m>03'
The docs state this, as well as the docstring for bytes:
>>> help(bytes)
...
bytes(int) -> bytes object of size given by the parameter initialized with null bytes
...
Unicode character in PHP string
...
Because JSON directly supports the \um>x m>m>x m>m>x m>m>x m> syntam>x m> the first thing that comes into my mind is:
$unicodeChar = '\u1000';
echo json_decode('"'.$unicodeChar.'"');
Another option would be to use mb_convert_encoding()
echo mb_convert_encoding('&#m>x m>1000;', 'UTF-8...
Remove columns from dataframe where ALL values are NA
... more memory and time efficient
An approach using Filter
Filter(function(m>x m>)!all(is.na(m>x m>)), df)
and an approach using data.table (for general time and memory efficiency)
library(data.table)
DT <- as.data.table(df)
DT[,which(unlist(lapply(DT, function(m>x m>)!all(is.na(m>x m>))))),with=F]
em>x m>amples usi...
Scatterplot with too many points
...oint plotted on them.
This is easy to do in ggplot2:
df <- data.frame(m>x m> = rnorm(5000),y=rnorm(5000))
ggplot(df,aes(m>x m>=m>x m>,y=y)) + geom_point(alpha = 0.3)
Another convenient way to deal with this is (and probably more appropriate for the number of points you have) is hem>x m>agonal binning:
ggplot(...
How to make lists contain only distinct element in Python? [duplicate]
... ''' Modified version of Dave Kirby solution '''
seen = set()
return [m>x m> for m>x m> in seq if m>x m> not in seen and not seen.add(m>x m>)]
OK, now how does it work, because it's a little bit tricky here if m>x m> not in seen and not seen.add(m>x m>):
In [1]: 0 not in [1,2,3] and not print('add')
add
Out[1]: True
Wh...
How to Correctly Use Lists in R?
...ints out the difference between a list and vector in R:
Why do these two em>x m>pressions not return the same result?
m>x m> = list(1, 2, 3, 4); m>x m>2 = list(1:4)
A list can contain any other class as each element. So you can have a list where the first element is a character vector, the second is a data fram...
case-insensitive list sorting, without lowercasing the result?
...trings, since they both have a lower method.
In Python 2 it works for a mim>x m> of normal and unicode strings, since values of the two types can be compared with each other. Python 3 doesn't work like that, though: you can't compare a byte string and a unicode string, so in Python 3 you should do the s...