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The difference between bracket [ ] and double bracket [[ ]] for accessing the elements of a list or
...urn the ith sequential element of x.
For lists, one generally uses [[ to select any single element, whereas [ returns a list of the selected elements.
The [[ form allows only a single element to be selected using integer or character indices, whereas [ allows indexing by vectors. Note though tha...
Two single-column indexes vs one two-column index in MySQL?
... the statement I provided.
Additionally, MySQL can only use one index per SELECT so a covering index would be the best means of optimizing your queries.
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How to detect input type=file “change” for the same file?
I want to fire an event when the user select a file. Doing so with .change event it works if the user changes the file every time.
...
How to remove a project (from the workspace) in PHPStorm?
...el.)
1. Click File > Close project
2. From Recent projects, select project, press the fn(on normal keyboard - key between right Alt and Ctrl, not windows key)+Delete
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Case conventions on element names?
...inent examples:
<a>1</a><b>1</b>
<xsl:value-of select="a+b"/>
outputs 2, as expected
<a>1</a><b>1</b>
<xsl:value-of select="a-b"/>
DOES NOT ERROR, BUT OUTPUTS NOTHING AT ALL
In the above code, you must put at least one space before a su...
Why does the 260 character path length limit exist in Windows?
...raphs), the maximum length for a path is MAX_PATH, which is defined as 260 characters. A local path is structured in the following order: drive letter, colon, backslash, name components separated by backslashes, and a terminating null character. For example, the maximum path on drive D is "D:\some 2...
How do I enter RGB values into Interface Builder?
... enter RGB or Hex color values for backgrounds in Interface Builder? I can select predefined colors but I would like to manually enter in RGB values. Where can I do this?
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The ViewData item that has the key 'MY KEY' is of type 'System.String' but must be of type 'IEnumera
... same code used before, so repeat this:
var db = new DB();
IEnumerable<SelectListItem> basetypes = db.Basetypes.Select(
b => new SelectListItem { Value = b.basetype, Text = b.basetype });
ViewData["basetype"] = basetypes;
before the return View(meal) in the [HttpPost] method.
exactl...
Programmatically scroll to a specific position in an Android ListView
...
For a direct scroll:
getListView().setSelection(21);
For a smooth scroll:
getListView().smoothScrollToPosition(21);
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What characters are forbidden in Windows and Linux directory names?
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A “comprehensive guide” of forbidden filename characters is not going to work on Windows because it reserves filenames as well as characters. Yes, characters like
* " ? and others are forbidden, but there are a infinite number of names composed only of valid characters t...