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Performance difference between IIf() and If
...1
Sub Main()
Dim test As Boolean = False
Dim result As String = IIf(test, Foo(), Bar())
End Sub
Public Function Foo() As String
Console.WriteLine("Foo!")
Return "Foo"
End Function
Public Function Bar() As String
Console.WriteLine("Bar!")
...
read.csv warning 'EOF within quoted string' prevents complete reading of file
...ns.CSV", quote = "",
row.names = NULL,
stringsAsFactors = FALSE)
str(cit)
## 'data.frame': 112543 obs. of 13 variables:
## $ row.names : chr "10.2307/675394" "10.2307/30007362" "10.2307/4254931" "10.2307/20537934" ...
## $ id : chr "10.2307/6...
MySQL load NULL values from CSV data
...ual field value to NULL, if the local variable ends up containing an empty string:
LOAD DATA INFILE '/tmp/testdata.txt'
INTO TABLE moo
FIELDS TERMINATED BY ","
LINES TERMINATED BY "\n"
(one, two, three, @vfour, five)
SET four = NULLIF(@vfour,'')
;
If they're all possibly empty, then you'd read th...
Regular expression for letters, numbers and - _
...will be slightly more complicated.
The above regex also matches the empty string. If you need at least one character, then use + (one-or-more) instead of * (zero-or-more) for repetition.
In any case, you can further clarify your specification (always helps when asking regex question), but hopefull...
Android get free size of internal/external memory
... android.os.Environment.MEDIA_MOUNTED);
}
public static String getAvailableInternalMemorySize() {
File path = Environment.getDataDirectory();
StatFs stat = new StatFs(path.getPath());
long blockSize = stat.getBlockSizeLong();
long availableBlocks = ...
python list in sql query as parameter
...
Answers so far have been templating the values into a plain SQL string. That's absolutely fine for integers, but if we wanted to do it for strings we get the escaping issue.
Here's a variant using a parameterised query that would work for both:
placeholder= '?' # For SQLite. See DBAPI p...
Javascript dynamically invoke object method from string
Can I dynamically call an object method having the method name as a string? I would imagine it like this:
5 Answers
...
Using PowerShell to write a file in UTF-8 without the BOM
...Encoding class and passing $False to the constructor seems to work:
$MyRawString = Get-Content -Raw $MyPath
$Utf8NoBomEncoding = New-Object System.Text.UTF8Encoding $False
[System.IO.File]::WriteAllLines($MyPath, $MyRawString, $Utf8NoBomEncoding)
...
Android: how to make an activity return results to the activity which calls it?
...u can make use of setData() to return result.
Intent data = new Intent();
String text = "Result to be returned...."
//---set the data to pass back---
data.setData(Uri.parse(text));
setResult(RESULT_OK, data);
//---close the activity---
finish();
So then again in the first activity you write the b...
How to get current working directory in Java?
... .class file is in.
public class Test
{
public static void main(final String[] args)
{
final String dir = System.getProperty("user.dir");
System.out.println("current dir = " + dir);
}
}
if you are in /User/me/ and your .jar file containing the above code is in /opt/s...