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unix - head AND tail of file
... 10; my @buf = (); while (<>) { print if $. <= $size; push(@buf, $_); if ( @buf > $size ) { shift(@buf); } } print "------\n"; print @buf;'
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Entity Framework: There is already an open DataReader associated with this Command
...ng to iterate is kind of lazy loading (IQueriable).
foreach (var user in _dbContext.Users)
{
}
Converting the IQueriable collection into other enumerable collection will solve this problem.
example
_dbContext.Users.ToList()
Note: .ToList() creates a new set every-time and it can cause th...
ExpandableListView - hide indicator for groups with no children
... states.
When the group has no children, the corresponding state is 'state_empty'
See these reference links:
this and this
For state_empty, you can set a different image which is not confusing, or, simply use transparent color to display nothing...
Add this item in your stateful drawable along ...
Test whether a list contains a specific value in Clojure
...been the most important function for collections. en.wikipedia.org/wiki/Set_(mathematics)#Membership
– jgomo3
Apr 3 '18 at 11:52
...
E11000 duplicate key error index in mongodb mongoose
...xes
From comments:
Your error says that the key is named mydb.users.$email_1 which makes me suspect that you have an index on both users.email and users.local.email (The former being old and unused at the moment). Removing a field from a Mongoose model doesn't affect the database. Check with mydb.u...
Convert NSDate to NSString
...less ARC is active
[formatter release];
Swift 4.2 :
func stringFromDate(_ date: Date) -> String {
let formatter = DateFormatter()
formatter.dateFormat = "dd MMM yyyy HH:mm" //yyyy
return formatter.string(from: date)
}
...
How do I read an attribute on a class at runtime?
...fo) As TAttribute
Return info.GetCustomAttributes(GetType(TAttribute), _
False).FirstOrDefault()
End Function
' Example usage over PropertyInfo
Dim fieldAttr = GetAttribute(Of DataObjectFieldAttribute)(pInfo)
If fieldAttr IsNot Nothing AndAlso fieldAttr.Prima...
In Scala how do I remove duplicates from a list?
...
removeDuplicates(tail.filter(_ != head))
– jwvh
Sep 13 at 22:50
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How do you change the size of figures drawn with matplotlib?
...ure created you can quickly do this:
fig = matplotlib.pyplot.gcf()
fig.set_size_inches(18.5, 10.5)
fig.savefig('test2png.png', dpi=100)
To propagate the size change to an existing gui window add forward=True
fig.set_size_inches(18.5, 10.5, forward=True)
...
What's the main difference between int.Parse() and Convert.ToInt32
... throw new OverflowException(Environment.GetResourceString("Overflow_Int32"));
}
return num;
}
if (!NumberToInt32(ref number, ref num))
{
throw new OverflowException(Environment.GetResourceString("Overflow_Int32"));
}
return num;
}
Convert.ToInt32...