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How to Correctly Use Lists in R?
...dresses the question of the difference between [] and [[]].
In short [[]] selects a single item from a list and [] returns a list of the selected items. In your example, x = list(1, 2, 3, 4)' item 1 is a single integer but x[[1]] returns a single 1 and x[1] returns a list with only one value.
>...
Difference between save and saveAndFlush in Spring data jpa
... flush mode AUTO and you are using your application to first save and then select the data again, you will not see a difference in bahvior between save() and saveAndFlush() because the select triggers a flush first. See the documention.
...
Sqlite LIMIT / OFFSET query
...< 100000; i++)
{
//first version
timeLimitOffset += SqlDuraction("Select * from table1 order by col1 LIMIT " + (i + 1) + " OFFSET " + (1001 - i) + "");
// second version
timeLimitComma += SqlDuraction("Select * from table1 order by col1 LIMIT " + (1001 - i) + " , " + (i + 1) + "");
}...
Is there a way to create multiline comments in Python?
...
In any case, your text editor should also be able to easily comment-out a selected region (by placing a # in front of each line individually). If not, switch to a text editor that does.
Programming in Python without certain text editing features can be a painful experience. Finding the right edito...
Changing Ctrl + Tab behavior for moving between documents in Visual Studio
...w place cursor in the Press shortcut keys: textbox (doesn't matter what is selected currently, you're not going to Assign this time), and type first of the three (or two or one) shortcuts.
You'll see Shortcut currently used by: listed. Ensure that you have no duplicate entry for the shortcut. In...
Check if a dialog is displayed with Espresso
... correct button in the dialog.
UiObject button = uiDevice.findObject(new UiSelector().text("ButtonText"));
if (button.exists() && button.isEnabled()) {
button.click();
}
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How do I remove the “extended attributes” on a file in Mac OS X?
...
Answer (Individual Files)
1. Showcase keys to use in selection.
xattr ~/Desktop/screenshot\ 2019-10-23\ at\ 010212.png
# com.apple.FinderInfo
# com.apple.lastuseddate#PS
# com.apple.metadata:kMDItemIsScreenCapture
# com.apple.metadata:kMDItemScreenCaptureGlobal...
Should I compile with /MD or /MT?
...nes _MT so that multithread-specific versions of the run-time routines are selected from the standard header (.h) files. This option also causes the compiler to place the library name LIBCMT.lib into the .obj file so that the linker will use LIBCMT.lib to resolve external symbols. Either /MT or /MD ...
Does MongoDB's $in clause guarantee order
...ocuments are retrieved. That of course will be the natural order or by the selected index order as shown.
If you need to preserve this order, then you basically have two options.
So let's say that you were matching on the values of _id in your documents with an array that is going to be passed in ...
What does a space mean in a CSS selector? i.e. What is the difference between .classA.classB and .cl
What is the difference between these two selectors?
3 Answers
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