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Select rows of a matrix that meet a condition
...20, ncol = 4)
colnames(m) <- letters[1:4]
The following command will select the first row of the matrix above.
subset(m, m[,4] == 16)
And this will select the last three.
subset(m, m[,4] > 17)
The result will be a matrix in both cases.
If you want to use column names to select columns...
Printing the value of a variable in SQL Developer
...utput).
Press the "+" button at the top of the Dbms Output window and then select an open database connection in the dialog that opens.
In SQL*Plus:
SET SERVEROUTPUT ON
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Auto-expanding layout with Qt-Designer
...your widget/dialog/window (not the QVBoxLayout, but the parent widget) and select Lay Out -> Lay Out in a Grid from the bottom of the context-menu. The QVBoxLayout should now stretch to fit the window and will resize automatically when the entire window is resized.
...
Django select only rows with duplicate field values
...ithout this, the subquery fails. The extra values tricks the ORM into only selecting the name column for the subquery.
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jQuery set radio button
...
Your selector looks for the descendant of a input:radio[name=cols] element that has the id of newcol (well the value of that variable).
Try this instead (since you're selecting by ID anyway):
$('#' + newcol).prop('checked',true)...
How to change the Eclipse default workspace?
...down>Workspaces.
There you can set a flag to make Eclipse prompt you to select a workspace at startup by checking the "Prompt for workspace at startup" checkbox.
You can set the number of previous workspaces to remember also. Finally there is a list of recent workspaces. If you just remove all b...
Modifying location.hash without page scrolling
... load
if(document.location.hash){
$("#buttons li a").removeClass('selected');
s=$(document.location.hash.replace("btn_","")).addClass('selected').attr("href").replace("javascript:","");
eval(s);
}
//Click a button to change the hash
$("#buttons li a").click(function()...
Convert a string to int using sql query
...
You could use CAST or CONVERT:
SELECT CAST(MyVarcharCol AS INT) FROM Table
SELECT CONVERT(INT, MyVarcharCol) FROM Table
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Where is android studio building my .apk file?
...
Go to AndroidStudio projects File
Select the project name,
Select app
Select build
Select Outputs
Select Apk
You will find APK files of app here, if you have ran the app in AVD or even hardware device
...
How to hide one item in an Android Spinner
...d spinner widget. This would allow you to simulate a spinner with no items selected, and ensures that the onItemSelected() callback is always called for every item selected (if the hidden item is the "current" one). Normally there is always one item in the spinner that doesn't generate a callback, n...