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What does .SD stand for in data.table in R
...mples below, this is particularly helpful for chaining together "queries" (extractions/subsets/etc using [). In particular, this also means that .SD is itself a data.table (with the caveat that it does not allow assignment with :=).
The simpler usage of .SD is for column subsetting (i.e., when .SDc...
Developing for Android in Eclipse: R.java not regenerating
...e of them recently
Check AndroidManifest.xml. I find that often I change a string and forget to change the string name from AndroidManifest.xml.
Check that Android SDK Build-tools is installed. Window -> Android SDK Manager -> Tools -> Android SDK Build-tools
Make sure when you update the A...
Arrow operator (->) usage in C
...ore legible foo*.bar. The whole mess of typedef-ing functions with all the extra parentheses would have been avoided as well.
– Marquis of Lorne
Jan 26 '15 at 6:04
...
'innerText' works in IE, but not in Firefox
...) nor orphaned from the document. Otherwise, innerText results in an empty string.
I was playing with textContent abstraction (to work around these deficiencies), but it turned out to be rather complex.
You best bet is to first define your exact requirements and follow from there. It is often poss...
What represents a double in sql server?
... I'll be darn; you're right! I wonder what SQL does with the extra bit; it's not used for the exponent. If it did, the exponent would go up to +-616 instead of +-308. Maybe to track NULL?
– Euro Micelli
Jul 30 '09 at 21:42
...
How do I make a splash screen?
...
<activity
android:name="MainActivity"
android:label="@string/app_name"
android:theme="@style/splashScreenTheme" >
Third, Update your theme in your onCreate() launch activity.
protected void onCreate(Bundle savedInstanceState) {
// Make sure this is before calli...
Overriding id on create in ActiveRecord
... @jkndrkn - I don't know what you mean. I've got ActiveRecord::VERSION::STRING == "3.2.11" here (with the sqlite3 adapter) and the above works for me.
– Felix Rabe
Feb 17 '13 at 18:43
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How to speed up insertion performance in PostgreSQL
...ack-on-errors to "Transaction" by specifying Protocol=-1 in the connection string. By default psqlodbc uses "Statement" level, which creates a SAVEPOINT for each statement rather than an entire transaction, making inserts slower.
Use server-side prepared statements by specifying UseServerSidePrepare...
Get data from fs.readFile
...file named filename.
If encoding is specified then this function returns a string. Otherwise it returns a buffer.
var text = fs.readFileSync('test.md','utf8')
console.log (text)
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How to add an object to an array
... aData) {
alert(aData[i].fullname());
}
/* convert array of object into string json */
var jsonString = JSON.stringify(aData);
document.write(jsonString);
Push object into array
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