instance

问题 While it has been previously answered how to fake isinstance, in this case I'm trying to fake the response given by type() while reviewing the TypeChanger class. For context Im just trying to understand if is doable or not and why for Python 3.X This is my current test setup: def test(): class TypeChanger(): @classmethod def __instancecheck__(cls, instance): if instance is list: return True else: return False @property def __class__(self): return list def extra_functionality(self): return

问题 I need to create an instance in class Crop of Plant class and i cant manage to find a way to make that work. Hope you guys can help at that. This my main where i'm sending an object to the class crop. int main(){ char select = 'a'; int plant_num = 2; int crop_num = 0; Crop crop[10]; Plant plant[20]; plant[0] = Plant("Carrots",'c'); plant[1] = Plant("Lettuce",'l'); plant[2] = Plant("Rosemary",'r'); crop[0] = Crop(plant[0],4,2); crop_num++; cout << "Garden Designer" << endl; cout << "==========

问题 I have a spark DataFrame. Now I want to do some processing using Weka. Therefore, I want to load data into Weka Instances from the DataFrame and finally return the data as a DataFrame. As the structure both the data type is different, I wondering can anybody help me with the conversion. The code snippet may look like below. val df: DataFrame = data val data: Instances = process(df) 来源： https://stackoverflow.com/questions/58160584/how-to-load-data-in-weka-instances-from-a-spark-dataframe

问题 I tried to instance many cubes side by side each other. My understanding is that I need to create a MVP matrix for each cube and bind this then somehow change the position. then run this in a for loop for how many cubes you'd want. This is what I've tried: while (!glfwWindowShouldClose(window)) { glClearColor(0.0f / 255.0f, 170.0f / 255.0f, 204.0f / 255.0f, 0.0f); glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); glUseProgram(programID); glEnableVertexAttribArray(0); glBindBuffer(GL_ARRAY

问题 As far as I know, interfaces cannot be instantiated. If this is true, why does the below code compile and execute? It allows you to create a variable interface. Why is this possible? Interface: public interface IDynamicCode<out TCodeOut> { object DynamicClassInstance { get; set; } TCodeOut Execute(string value = ""); } InCode: var x = new IDynamicCode<string>[10]; Result: UPDATE: It only happens when array declared. Not a single instance. 回答1: You're not instantiating an interface, but an

问题 I know that you can call an instance method that executes for each object. I also know that you can have a static method on the type that is callable from the type. But how would one call a method that acts on every instance of a particular type (say, to set a member variable to zero, for example)? 回答1: C# doesn't provide a direct mechanism to track all reachable objects and there's almost never a good reason to want such automatic tracking functionality (rather than, say, an explicit pool

问题 I know that you can call an instance method that executes for each object. I also know that you can have a static method on the type that is callable from the type. But how would one call a method that acts on every instance of a particular type (say, to set a member variable to zero, for example)? 回答1: C# doesn't provide a direct mechanism to track all reachable objects and there's almost never a good reason to want such automatic tracking functionality (rather than, say, an explicit pool

问题 I know that you can call an instance method that executes for each object. I also know that you can have a static method on the type that is callable from the type. But how would one call a method that acts on every instance of a particular type (say, to set a member variable to zero, for example)? 回答1: C# doesn't provide a direct mechanism to track all reachable objects and there's almost never a good reason to want such automatic tracking functionality (rather than, say, an explicit pool

问题 I'm a beginner in using AWS. I just want to stop and start several EC2 instances automatically and periodically(Not reboot). Is there any recommended way to do this? 回答1: Amazon recently (Feb 2018) released the EC2 instance scheduler tool: The AWS Instance Scheduler is a simple AWS-provided solution that enables customers to easily configure custom start and stop schedules for their Amazon Elastic Compute Cloud (Amazon EC2) and Amazon Relational Database Service (Amazon RDS) instances. The

问题 I'm a beginner in using AWS. I just want to stop and start several EC2 instances automatically and periodically(Not reboot). Is there any recommended way to do this? 回答1: Amazon recently (Feb 2018) released the EC2 instance scheduler tool: The AWS Instance Scheduler is a simple AWS-provided solution that enables customers to easily configure custom start and stop schedules for their Amazon Elastic Compute Cloud (Amazon EC2) and Amazon Relational Database Service (Amazon RDS) instances. The