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Drop columns whose name contains a specific string from pandas DataFrame
...er, and Idiomatic: str.contains
In recent versions of pandas, you can use string methods on the index and columns. Here, str.startswith seems like a good fit.
To remove all columns starting with a given substring:
df.columns.str.startswith('Test')
# array([ True, False, False, False])
df.loc[:,~...
Does ruby have real multithreading?
...ing
models.
(Unfortunately, only two of those 11 implementations are actually
ready for production use, but by the end of the year that number
will probably go up to four or five.) (Update: it's now 5: MRI, JRuby, YARV (the interpreter for Ruby 1.9), Rubinius and IronRuby).
The first implement...
How to set top-left alignment for UILabel for iOS application?
...turn nil;
// set inital value via IVAR so the setter isn't called
_verticalAlignment = VerticalAlignmentTop;
return self;
}
-(VerticalAlignment) verticalAlignment
{
return _verticalAlignment;
}
-(void) setVerticalAlignment:(VerticalAlignment)value
{
_verticalAlignment = value...
How to use JavaScript regex over multiple lines?
...
To match an entire multiline string, try the greedy [\s\S]+.
– Boaz
Oct 29 '18 at 14:42
...
How can I perform a culture-sensitive “starts-with” operation from the middle of a string?
... a simple one-to-one mapping.
You would need to know the length of the substring that was actually matched. But Compare, IndexOf ..etc
throw that information away. It could be possible with regular expressions but the implementation doesn't do full case folding and so doesn't match
ß to ss/SS in c...
How to check for file lock? [duplicate]
...lar problem, I finished with the following code:
public bool IsFileLocked(string filePath)
{
try
{
using (File.Open(filePath, FileMode.Open)){}
}
catch (IOException e)
{
var errorCode = Marshal.GetHRForException(e) & ((1 << 16) - 1);
return err...
How to find third or nth maximum salary from salary table?
...
Use ROW_NUMBER(if you want a single) or DENSE_RANK(for all related rows):
WITH CTE AS
(
SELECT EmpID, EmpName, EmpSalary,
RN = ROW_NUMBER() OVER (ORDER BY EmpSalary DESC)
FROM dbo.Salary
)
SELECT EmpID, EmpName, EmpSalary
FROM CTE
WHERE RN = @NthRow
...
How to concatenate items in a list to a single string?
Is there a simpler way to concatenate string items in a list into a single string? Can I use the str.join() function?
11...
Why does parseInt(1/0, 19) return 18?
...
The result of 1/0 is Infinity.
parseInt treats its first argument as a string which means first of all Infinity.toString() is called, producing the string "Infinity". So it works the same as if you asked it to convert "Infinity" in base 19 to decimal.
Here are the digits in base 19 along with t...
How can I get enum possible values in a MySQL database?
...
You can get the values by querying it like this:
SELECT SUBSTRING(COLUMN_TYPE,5)
FROM information_schema.COLUMNS
WHERE TABLE_SCHEMA='databasename'
AND TABLE_NAME='tablename'
AND COLUMN_NAME='columnname'
From there you'll need to convert it into an array:
eval that direct...