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Error: Could not find or load main class in intelliJ IDE
I'm a beginner in Java and am trying to run my code using IntelliJ that I just installed as my IDE with JDK 1.7. The following piece of code keeps does not even compile and keeps giving me the error:
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How can I check whether a numpy array is empty or not?
...an always take a look at the .size attribute. It is defined as an integer, and is zero (0) when there are no elements in the array:
import numpy as np
a = np.array([])
if a.size == 0:
# Do something when `a` is empty
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Gmail Error :The SMTP server requires a secure connection or the client was not authenticated. The s
...in from different time zone or IP Address Computer. Your production server and the mail id you have used both are in different time zone. Choose either of these two solutions:
1) Log in to production server via remote access, and sign in to gmail once with your credentials. They will ask for the co...
Array versus linked-list
...er of changing what points to what. Shuffling an array is more complicated and/or takes more memory.
As long as your iterations all happen in a "foreach" context, you don't lose any performance in iteration.
share
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Confusion between factor levels and factor labels
There seems to be a difference between levels and labels of a factor in R.
Up to now, I always thought that levels were the 'real' name of factor levels, and labels were the names used for output (such as tables and plots). Obviously, this is not the case, as the following example shows:
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Which SQL query is faster? Filter on Join criteria or Where clause?
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Performance-wise, they are the same (and produce the same plans)
Logically, you should make the operation that still has sense if you replace INNER JOIN with a LEFT JOIN.
In your very case this will look like this:
SELECT *
FROM TableA a
LEFT JOIN
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Entity Framework 4 Single() vs First() vs FirstOrDefault()
...ime finding a comparison of the different ways to query for a single item, and when to use each.
6 Answers
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Why does ++[[]][+[]]+[+[]] return the string “10”?
This is valid and returns the string "10" in JavaScript ( more examples here ):
9 Answers
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What's the difference between a web site and a web application? [closed]
I'm stumped trying to come up to a difference between a website and a web application for myself. As I see it, a web site points to a specific page and a web application is more of some sort of 'portal' to content and information.
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How to call an async method from a getter or setter?
...int (2) wouldn't work in that case. Just implement INotifyPropertyChanged, and then decide whether you want the old value returned or default(T) while the asynchronous update is in flight.
– Stephen Cleary
Nov 19 '13 at 11:57
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