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Remove an entire column from a data.frame in R
...=4:6)
to remove just the a column you could do
Data <- subset( Data, select = -a )
and to remove the b and d columns you could do
Data <- subset( Data, select = -c(d, b ) )
You can remove all columns between d and b with:
Data <- subset( Data, select = -c( d : b )
As I said above...
Get record counts for all tables in MySQL database
...get the count of rows in all tables in a MySQL database without running a SELECT count() on each table?
19 Answers
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How do I UPDATE from a SELECT in SQL Server?
... SQL Server , it is possible to insert rows into a table with an INSERT.. SELECT statement:
35 Answers
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jQuery remove options from select
I have a page with 5 selects that all have a class name 'ct'. I need to remove the option with a value of 'X' from each select while running an onclick event. My code is:
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SQL query to select dates between two dates
...
you should put those two dates between single quotes like..
select Date, TotalAllowance from Calculation where EmployeeId = 1
and Date between '2011/02/25' and '2011/02/27'
or can use
select Date, TotalAllowance from Calculation where EmployeeId = 1
and Da...
MySQL Query to select data from last week?
Hi I have a table with a date field and some other information.
I want to select all entries from the past week, (week start from Sunday).
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Fast ceiling of an integer division in C / C++
... return res.rem ? (res.quot + 1) : res.quot;
}
int main(int, const char**)
{
std::cout << "10 / 5 = " << div_ceil(10, 5) << std::endl;
std::cout << "11 / 5 = " << div_ceil(11, 5) << std::endl;
return 0;
}
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jQuery If DIV Doesn't Have Class “x”
...y I need to do an if statement to see if $this doesn't contain the class '.selected'.
7 Answers
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How to comment and uncomment blocks of code in the Office VBA Editor
...tor, go to View, Toolbars, Customise... or right click on the tool bar and select Customise...
Under the Commands tab, select the Edit menu on the left.
Then approximately two thirds of the way down there's two icons, Comment Block and Uncomment Block.
Drag and drop these onto your toolbar and th...
Convert string to binary in python
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What about converting more-than-one-byte chars, like β, e.g., which seems to me represented by 11001110 10110010 internally?
– Sergey Bushmanov
Mar 25 '17 at 20:18
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