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How to declare std::unique_ptr and what is the use of it?
I try to understand how std::unique_ptr works and for that I found this document. The author starts from the following example:
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What does @: (at symbol colon) mean in a Makefile?
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It means "don't echo this command on the output." So this rule is saying "execute the shell command : and don't echo the output.
Of course the shell command : is a no-op, so this is saying "do nothing, and don't tell."
Why?
The trick here is that you'...
python pandas remove duplicate columns
... solution to the problem. This applies if some column names are duplicated and you wish to remove them:
df = df.loc[:,~df.columns.duplicated()]
How it works:
Suppose the columns of the data frame are ['alpha','beta','alpha']
df.columns.duplicated() returns a boolean array: a True or False for e...
What is the max size of localStorage values?
Since localStorage (currently) only supports strings as values, and in order to do that the objects need to be stringified (stored as JSON-string) before they can be stored, is there a defined limitation regarding the length of the values.
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Get lengths of a list in a jinja2 template
... products|length > 1 %}
jinja2's builtin filters are documented here; and specifically, as you've already found, length (and its synonym count) is documented to:
Return the number of items of a sequence or mapping.
So, again as you've found, {{products|count}} (or equivalently {{products|...
Check difference in seconds between two times
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Assuming dateTime1 and dateTime2 are DateTime values:
var diffInSeconds = (dateTime1 - dateTime2).TotalSeconds;
In your case, you 'd use DateTime.Now as one of the values and the time in the list as the other. Be careful of the order, as the...
Aggregate function in an SQL update query?
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I put the three queries side-by-side and ran an execution plan. This answer had a cost of 5%.
– Margaret
Jan 6 '10 at 0:24
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How to handle command-line arguments in PowerShell
What is the "best" way to handle command-line arguments?
1 Answer
1
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How to loop through files matching wildcard in batch file
...t of base filenames, for each name 'f' there are exactly two files, 'f.in' and 'f.out'. I want to write a batch file (in Windows XP) which goes through all the filenames, for each one it should:
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Create table with jQuery - append
...ntent);
But, with the above approach it is less manageable to add styles and do stuff dynamically with <table>.
But how about this one, it does what you expect nearly great:
var table = $('<table>').addClass('foo');
for(i=0; i<3; i++){
var row = $('<tr>').addClass('bar')...