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dplyr: “Error in n(): function should not be called directly”
...
120
I presume you have dplyr and plyr loaded in the same session. dplyr is not plyr. ddply is not a ...
Accessing class variables from a list comprehension in the class definition
...owing will fail:
class A:
a = 42
b = list(a + i for i in range(10))
So, to summarize: you cannot access the class scope from functions, list comprehensions or generator expressions enclosed in that scope; they act as if that scope does not exist. In Python 2, list comprehensions were i...
make arrayList.toArray() return more specific types
...ist = new ArrayList<String>();
String[] a = list.toArray(new String[0]);
Before Java6 it was recommended to write:
String[] a = list.toArray(new String[list.size()]);
because the internal implementation would realloc a properly sized array anyway so you were better doing it upfront. Sinc...
How to get element by classname or id
... to access the DOM reference instead of the the jqLite reference - element[0] instead of element:
link: function (scope, element, attrs) {
var elementResult = element[0].getElementsByClassName('multi-files');
}
Alternatively you can use the document.querySelector function (need the period here...
JSON.parse unexpected character error
...rsing an already-parsed object :)
var obj1 = JSON.parse('{"creditBalance":0,...,"starStatus":false}');
// ^ ^
// if you want to parse, the input should be a string
var obj2 = {"creditBalance":0,...,"starStatus":false};...
Simplest code for array intersection in javascript
... Ry-♦
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answered Dec 11 '09 at 3:08
Anon.Anon.
49.5k88 gold badges...
Clearing a string buffer/builder after loop
...ete method as follows:
StringBuffer sb = new StringBuffer();
for (int n = 0; n < 10; n++) {
sb.append("a");
// This will clear the buffer
sb.delete(0, sb.length());
}
Another option (bit cleaner) uses setLength(int len):
sb.setLength(0);
See Javadoc for more info:
...
Purge Kafka Topic
...;zkhost>:2181 --alter --topic <topic name> --config retention.ms=1000
And in newer Kafka releases, you can also do it with kafka-configs --entity-type topics
kafka-configs.sh --zookeeper <zkhost>:2181 --entity-type topics --alter --entity-name <topic name> --add-config retent...
How to create NS_OPTIONS-style bitmask enumerations in Swift?
...
Swift 3.0
Almost identical to Swift 2.0. OptionSetType was renamed to OptionSet and enums are written lower case by convention.
struct MyOptions : OptionSet {
let rawValue: Int
static let firstOption = MyOptions(rawValue:...
Returning a boolean from a Bash function
...
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