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Pass a data.frame column name to a function
...(x[,column])
}
fun1(df, "B", max)
Alternatively, using [[ also works for selecting a single column at a time:
df <- data.frame(A=1:10, B=2:11, C=3:12)
fun1 <- function(x, column){
max(x[[column]])
}
fun1(df, "B")
...
Failed to load c++ bson extension
...vailable when you installed your mongodb library. I suggest you do
xcode-select --install (on a mac)
or sudo apt-get install gcc make build-essential (on ubuntu)
and run
rm -rf node_modules
npm cache clean
npm install
OR just npm update based on @tobias comment (after installing build-essenti...
How to get the list of all installed color schemes in Vim?
...a list of all installed color schemes in Vim? That would make very easy to select one without looking at the .vim directory.
...
Surrogate vs. natural/business keys [closed]
...ot more tables into your query than should really be necessary. Compare:
select sum(t.hours)
from timesheets t
where t.dept_code = 'HR'
and t.status = 'VALID'
and t.project_code = 'MYPROJECT'
and t.task = 'BUILD';
against:
select sum(t.hours)
from timesheets t
join departents d on d.dept_i...
Maintain/Save/Restore scroll position when returning to a ListView
... - mList.getPaddingTop());
// ...
// restore index and position
mList.setSelectionFromTop(index, top);
Explanation:
ListView.getFirstVisiblePosition() returns the top visible list item. But this item may be partially scrolled out of view, and if you want to restore the exact scroll position of t...
Word wrap for a label in Windows Forms
...
Select the label you're dynamically adding text to. Look at the properties for the label and turn off AutoSize. You will now be able to drag/set the area for the label and it will automatically auto-wrap to stay within those...
How to upgrade all Python packages with pip?
... install pip-review
$ py -3 -m pip_review --local --interactive
You can select 'a' to upgrade all packages; if one upgrade fails, run it again and it continues at the next one.
share
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improve th...
Debugging with command-line parameters in Visual Studio
...
Make sure you have the correct Configuration selected in the dropdown at the top of the Property pages, i.e. the same configuration as the one you are trying to run.
– Steve Smith
Jan 4 '18 at 14:51
...
Maven Install on Mac OS X
...t:~$ sudo port install maven3 will Install Maven 3.0
you@host:~$ sudo port select --set maven maven3 selects that version of Maven
Installing by hand:
Download Maven from its homepage
Follow the installation instructions:
Extract the distribution archive, i.e.apache-maven-3.3.9-bin.tar.gz to th...
Slicing of a NumPy 2d array, or how do I extract an mxm submatrix from an nxn array (n>m)?
I want to slice a NumPy nxn array. I want to extract an arbitrary selection of m rows and columns of that array (i.e. without any pattern in the numbers of rows/columns), making it a new, mxm array. For this example let us say the array is 4x4 and I want to extract a 2x2 array from it.
...