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if (key in object) or if(object.hasOwnProperty(key)
...type
If we want to check that some property exist on the prototype, logically, we would say:
console.log(('name' in o) && !o.hasOwnProperty('name')); //false
console.log(('gender' in o) && !o.hasOwnProperty('gender')); //true - it's in prototype
Finally:
So, regarding to statem...
How to select the row with the maximum value in each group
...ata.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 2
If you'd like ju...
AWS S3: The bucket you are attempting to access must be addressed using the specified endpoint
...ting to access must be addressed using the specified endpoint. Please send all future requests to this endpoint."
US Standard is us-east-1
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How do I fix "The expression of type List needs unchecked conversion…'?
...);
for(Object o: c)
r.add(clazz.cast(o));
return r;
}
This allows you to do:
List<SyndEntry> entries = castList(SyndEntry.class, sf.getEntries());
Because this solution checks that the elements indeed have the correct element type by means of a cast, it is safe, and does not...
Error: allowDefinition='MachineToApplication' beyond application level
...
A clean and rebuild while in debug mode are all that is needed for me. No need to switch back and forth between release and debug. But yes, the CLEAN is very important. That's the heart of the matter.
– markaaronky
Feb 12 '16 a...
Making an array of integers in iOS
...rays are such a hassle for anything but trivial, one-off use that it's actually less trouble to wrap any arrays you plan on keeping around as NSArrays of NSNumber.
– Chuck
Jul 27 '10 at 1:58
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How to split data into training/testing sets using sample function
...
@VedaadShakib when you use "-" it omit all the index in train_ind from your data. Take a look at adv-r.had.co.nz/Subsetting.html . Hope it helps
– dickoa
Aug 1 '16 at 22:05
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Is there a way to check if WPF is currently executing in design mode or not?
... while in Visual Studio:
DesignerProperties.IsInDesignTool
Edit: And finally, in the interest of completeness, the equivalent in WinRT / Metro / Windows Store applications is DesignModeEnabled:
Windows.ApplicationModel.DesignMode.DesignModeEnabled
...
Concatenating null strings in Java [duplicate]
...can do so yourself by using javap -c)
The append methods of StringBuilder all handle null just fine. In this case because null is the first argument, String.valueOf() is invoked instead since StringBuilder does not have a constructor that takes any arbitrary reference type.
If you were to have ...
Yes or No confirm box using jQuery
...false;
}
});
</script>
These codes works for me, but I'm not really sure if this is proper. What do you think?
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