The ellipsis is used in numpy to slice higher-dimensional data structures. It’s designed to mean at this point, insert as many full slices (:) to extend the multi-dimensional slice to all dimensions. Example: >>> from numpy import arange >>> a = arange(16).reshape(2,2,2,2) Now, you have a 4-dimensional matrix of order 2x2x2x2. To select all first … Read more
This is one of the problems of using visible fields – you end up using them… You’ve got a color field in both Rect and CRect. Fields are not polymorphic, so when you use cr2.color, that uses the field declared in Rect, which is always set to “transparent”. Your CRect class should not have its … Read more
Because tuples are immutable, you have to override __new__ instead: python docs object.__new__(cls[, …]) Called to create a new instance of class cls. __new__() is a static method (special-cased so you need not declare it as such) that takes the class of which an instance was requested as its first argument. The remaining arguments are … Read more
Apparently, no. Here’s the options: Use Type.IsSubclassOf Use Type.IsAssignableFrom is and as Type.IsSubclassOf As you’ve already found out, this will not work if the two types are the same, here’s a sample LINQPad program that demonstrates: void Main() { typeof(Derived).IsSubclassOf(typeof(Base)).Dump(); typeof(Base).IsSubclassOf(typeof(Base)).Dump(); } public class Base { } public class Derived : Base { } Output: … Read more
New-style classes (i.e. subclassed from object, which is the default in Python 3) have a __subclasses__ method which returns the subclasses: class Foo(object): pass class Bar(Foo): pass class Baz(Foo): pass class Bing(Bar): pass Here are the names of the subclasses: print([cls.__name__ for cls in Foo.__subclasses__()]) # [‘Bar’, ‘Baz’] Here are the subclasses themselves: print(Foo.__subclasses__()) # … Read more
Scanning for classes is not easy with pure Java. The spring framework offers a class called ClassPathScanningCandidateComponentProvider that can do what you need. The following example would find all subclasses of MyClass in the package org.example.package ClassPathScanningCandidateComponentProvider provider = new ClassPathScanningCandidateComponentProvider(false); provider.addIncludeFilter(new AssignableTypeFilter(MyClass.class)); // scan in org.example.package Set<BeanDefinition> components = provider.findCandidateComponents(“org/example/package”); for (BeanDefinition component : … Read more