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The difference between bracket [ ] and double bracket [[ ]] for accessing the elements of a list or
...ist(c("a", "b", "c"), c(1,2,3,4), c(8e6, 5.2e9, -9.3e7))
str(alist[[1]])
chr [1:3] "a" "b" "c"
str(alist[1])
List of 1
$ : chr [1:3] "a" "b" "c"
str(alist[[1]][1])
chr "a"
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Summarizing multiple columns with dplyr? [duplicate]
...
The dplyr package contains summarise_all for this aim:
library(dplyr)
df %>% group_by(grp) %>% summarise_all(list(mean))
#> # A tibble: 3 x 5
#> grp a b c d
#> <int> <dbl> <dbl> <dbl> <dbl>
#>...
Php multiple delimiters in explode
...
You can take the first string, replace all the @ with vs using str_replace, then explode on vs or vice versa.
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In Python, how do I create a string of n characters in one line of code?
...ly, of course;-).
Other ways to "make a string of 10 characters": 'x'*10 (all the ten characters will be lowercase xs;-), ''.join(chr(ord('a')+i) for i in xrange(10)) (the first ten lowercase letters again), etc, etc;-).
sh...
Is it possible to force Excel recognize UTF-8 CSV files automatically?
...s. The application always uses UTF-8 because of its multilingual nature at all levels. But opening such CSV files (containing e.g. diacritics, cyrillic letters, Greek letters) in Excel does not achieve the expected results showing something like Г„/Г¤, Г–/Г¶ . And I don't know how to forc...
Generate a Hash from string in Javascript
...String.prototype, 'hashCode', {
value: function() {
var hash = 0, i, chr;
for (i = 0; i < this.length; i++) {
chr = this.charCodeAt(i);
hash = ((hash << 5) - hash) + chr;
hash |= 0; // Convert to 32bit integer
}
return hash;
}
});
Source:
http://we...
convert '1' to '0001' in JavaScript [duplicate]
... if you don't want to use Array:
number.prototype.padLeft = function (len,chr) {
var self = Math.abs(this)+'';
return (this<0 && '-' || '')+
(String(Math.pow( 10, (len || 2)-self.length))
.slice(1).replace(/0/g,chr||'0') + self);
}
...
How to remove all whitespace from a string?
...\r\v\fy \t\n\r\v\f"
## [4] NA
The base R approach: gsub
gsub replaces all instances of a string (fixed = TRUE) or regular expression (fixed = FALSE, the default) with another string. To remove all spaces, use:
gsub(" ", "", x, fixed = TRUE)
## [1] "xy" "←→" ...
What is the source code of the “this” module doing?
...t13 encoding:
d = {}
for c in (65, 97):
for i in range(26):
d[chr(i+c)] = chr((i+13) % 26 + c)
Builds the translation table, for both uppercase (this is what 65 is for) and lowercase (this is what 97 is for) chars.
print "".join([d.get(c, c) for c in s])
Prints the translated strin...
In Python, how do I split a string and keep the separators?
...of pattern. If capturing parentheses are used in pattern, then the text of all groups in the pattern are also returned as part of the resulting list."
– Vinay Sajip
Jan 25 '10 at 23:54
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