casting

问题 I am trying to convert a varchar field to decimal field in db2 but I am getting an error AMOUNT field is a varchar field which needs to be converted to decimal(31,3) Given below is my query SELECT CAST(ROUND(TRIM(AMOUNT),3) AS DECIMAL(31,3)) FROM TABLENAME Note: AMOUNT field (varchar) has a NULL value as well Sample values: 7.324088 -42.97209 854 NULL 6 6 350 -6 15.380584 1900 I get the below error: Invalid character found in a character string argument of the function "DECFLOAT". SQLSTATE

问题 I have a given interface called IAbc, which consists of a method with a parameter of interface IXyz. I am not sure whether I should create an attribute IXyz or an attribute XyzImpl in my implementation of IAbc. public interface IXyz { } public class XyzImpl implements IXyz { public void doSomething() { ... } } public interface IAbc { public void setXyz(IXyz val); public IXyz getXyz(); } Implementation 1: public class AbcImpl1 implements IAbc { private XyzImpl attr; public void setXyz(IXyz val

问题 I have a List<string> List<string> students; students.Add("Rob"); students.Add("Schulz"); and a Dictionary<string,string> Dictionary<string, string> classes= new Dictionary<string, string>(); classes.Add("Rob", "Chemistry"); classes.Add("Bob", "Math"); classes.Add("Holly", "Physics"); classes.Add("Schulz", "Botany"); My objective now is to get a List with the values - Chemistry and Botany - for which I am using this var filteredList = students.Where(k => classes.ContainsKey(k)) .Select(k =>

问题 I have a situation where in first class I declare array, and I pass it to another object, which prints name of elements in this array. It works, but when I input 'car.' in ReadCarNames ide doesn't suggest me 'name' ? I'm trying it in wing ide 4 pro. Can I cast car in method ReadCarNames ? ######################################################################## class MyClass: """""" #---------------------------------------------------------------------- def __init__(self): cars=[] cars.append

问题 Using V1.8 z/OS XL C compiler, with warnings jacked-up using INFO(ALL), I get the following warning on line 4 of the code below: WARNING CCN3196 Initialization between types "const int** const" and "int**" is not allowed. 1 int foo = 0; 2 int *ptr = &foo; 3 const int * const fixed_readonly_ptr = ptr; 4 const int ** const fixed_ptr_to_readonly_ptr = &ptr; I can't wrap my head around why I'm getting this warning. If I can assign an int pointer to a const pointer to const int (line 3), then why

问题 The below code won't work, I wanted to know how I can dynamically cast an instance to a type determined at runtime? Convert.ChangeType() returns an Object that still needs to be cast. So does all attempts to Invoke() a GetConstructor() or Activator.CreateInstance(), see below. At some point I need to explicitly cast in code, I'm hoping to avoid it or push it out as far as possible. Type type = Type.GetType ("RandomChildClass"); Object obj = Activator.CreateInstance (type, new Object[]{

问题 I'm trying to add plugins to my program, and this looks good, except that I can't cast the correct type from the dll. I Have a solution with several projects on it. One of the project is a country Layer, that actually holds a CountryBase (defined as public abstract class CountryBase : CountryLayers.ICountryBase ) The Interface (public interface ICountryBase) On Another project I have the "Implementation" for the country. This dll is loaded at run time, using this: Assembly assembly = Assembly

问题 When representing two float32's as int32 or uint32 (using union or casting pointer types), Within a limited range (0..1), can these values be compared against each other, that would match the result of the comparison when executed as floats? Example: int float_as_int(float f) { union { int i; float f; } u; u.f = f; return u.i; } /* Assert the following is always true for values in a limited range. */ void assert_compare_works_as_expected(float a, float b) { assert(float_as_int(a) < float_as

问题 I'm trying to create a simple generic find function in TypeScript, along the lines of: export function findFirst<T, U>( array: T[], predicate: (item: T) => boolean, selector?: (item: T) => U): U { ... } So, my parameters are: - the array to filter through - a predicate to test each element - a selector to get the return value What I want to do is provide a default selector, i.e. if no selector is provided, just return the whole value, i.e. something like: if (typeof selector === "undefined")

问题 I am running an interactive python session which builds big python data-structures (5+ GB) which take a long time to load, and so I want to exploit Python on-the-fly code change abilities at its maximum (though sometimes, without having to plan too much for that ). My current problem is the following: I have an old instance of a class that I have later modified the code and reloaded the module -- I would like the old instance to be able to use the new function definitions. How do I do that