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Logical operators for boolean indexing in Pandas
...ear when it should be True or False. Some users might assume they are True if they have non-zero length, like a Python list. Others might desire for it to be True only if all its elements are True. Others might want it to be True if any of its elements are True.
Because there are so many conflicti...
How to loop through all the properties of a class?
... there is no "System.Reflection" entry in the list
Edit: You can also specify a BindingFlags value to type.GetProperties():
BindingFlags flags = BindingFlags.Public | BindingFlags.Instance;
PropertyInfo[] properties = type.GetProperties(flags);
That will restrict the returned properties to publi...
How to define a preprocessor symbol in Xcode
...is:
constant_1=VALUE constant_2=VALUE
Note that you don't need the '='s if you just want to #define a symbol, rather than giving it a value (for #ifdef statements)
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How to select the row with the maximum value in each group
...solution:
require(data.table) ## 1.9.2
group <- as.data.table(group)
If you want to keep all the entries corresponding to max values of pt within each group:
group[group[, .I[pt == max(pt)], by=Subject]$V1]
# Subject pt Event
# 1: 1 5 2
# 2: 2 17 2
# 3: 3 5 ...
How do I check (at runtime) if one class is a subclass of another?
...
If there's one thing that's a constant on Stack Overflow, it is that any questions with an answer that implies isinstance or issubclass will also be accompanied with lectures about duck typing!
– B Robst...
JQuery - $ is not defined
...ibutes async or defer.
Then you should check the Firebug net panel to see if the file is actually being loaded properly. If not, it will be highlighted red and will say "404" beside it. If the file is loading properly, that means that the issue is number 2.
Make sure all jQuery javascript code i...
Remove blank attributes from an Object in Javascript
... test3 : 3,
}
function clean(obj) {
for (var propName in obj) {
if (obj[propName] === null || obj[propName] === undefined) {
delete obj[propName];
}
}
}
clean(test);
If you're concerned about this property removal not running up object's proptype chain, you can also:
funct...
HTML5 Local Storage fallback solutions [closed]
...
cookie: Cookie-based persistent storage.
Any of those can be disabled—if, for example, you don't want to use cookies. With this library, you'll get native client-side storage support in IE 5.5+, Firefox 2.0+, Safari 3.1+, and Chrome; and plugin-assisted support if the browser has Flash or Gear...
When to use ko.utils.unwrapObservable?
...apObservable(item) Looking at the code, that call basically checks to see if item is an observable. If it is, return the value(), if it's not, just return the value. Looking at the section on Knockout about creating custom bindings, they have the following syntax:
...
How to ignore xargs commands if stdin input is empty?
...
For GNU xargs, you can use the -r or --no-run-if-empty option:
--no-run-if-empty
-r If the standard input does not contain any nonblanks, do not run the command. Normally, the command is run once even if there is no input. This option is a GNU extensi...