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Determine the data types of a data frame's columns
...integer" "logical" "factor"
Using str() gets you that information plus extra goodies (such as the levels of your factors and the first few values of each variable):
str(my.data)
'data.frame': 5 obs. of 4 variables:
$ y : num 1.03 1.599 -0.818 0.872 -2.682
$ x1: int 1 2 3 4 5
$ x2: logi T...
What's the difference between an object initializer and a constructor?
...nstances of one or more other classes. For example see File.Create Method (String) (and its overloads) which creates a FileStream object.
– DavidRR
Jan 17 '18 at 18:13
add a c...
Why Response.Redirect causes System.Threading.ThreadAbortException?
...ew Context)
{
User User = new User();
if (String.IsNullOrEmpty(model.EmailAddress))
ValidLogin = false; // no email address was entered
else
User = Db.FirstOrDefault(x => x.EmailAddress == model.EmailAddress);
...
Why not abstract fields?
...ised in its constructor (untested code):
abstract class Base {
final String errMsg;
Base(String msg) {
errMsg = msg;
}
abstract String doSomething();
}
class Sub extends Base {
Sub() {
super("Sub message");
}
String doSomething() {
return e...
Can someone explain __all__ in Python?
...xplicitly mentioned here, is exactly when __all__ is used. It is a list of strings defining what symbols in a module will be exported when from <module> import * is used on the module.
For example, the following code in a foo.py explicitly exports the symbols bar and baz:
__all__ = ['bar', '...
Easy pretty printing of floats in python?
...ise numbers, but get rid of trailing zeros for example, use the formatting string %g:
np.set_printoptions(formatter={"float_kind": lambda x: "%g" % x})
For just printing once and not changing global behavior, use np.array2string with the same arguments as above.
...
How to calculate the difference between two dates using PHP?
... displayed.
*
* @param DateInterval $interval The interval
*
* @return string Formatted interval string.
*/
function format_interval(DateInterval $interval) {
$result = "";
if ($interval->y) { $result .= $interval->format("%y years "); }
if ($interval->m) { $result .= $inte...
How to get my IP address programmatically on iOS/macOS?
...un0"
#define IP_ADDR_IPv4 @"ipv4"
#define IP_ADDR_IPv6 @"ipv6"
- (NSString *)getIPAddress:(BOOL)preferIPv4
{
NSArray *searchArray = preferIPv4 ?
@[ /*IOS_VPN @"/" IP_ADDR_IPv4, IOS_VPN @"/" IP_ADDR_IPv6,*/ IOS_WIFI @"/" IP_ADDR_IPv4, IOS_WIFI @"/" IP_ADDR_IPv6,...
How can you set class attributes from variable arguments (kwargs) in python
...args? Can kwargs even have an integer key? I'm pretty sure they have to be strings.
– wjandrea
Apr 22 at 19:12
...
Which is the fastest algorithm to find prime numbers?
... that gain is usually more than offset by the increased complexity and the extra constant factor overhead of this computational complexity such that for practical applications the SoE is better.
– GordonBGood
Mar 20 '14 at 2:53
...