error-handling

问题 I am running a fixed effects regression and am getting the following error: fixed_effects <- plm(GNI ~ lag(GNI) + imposition + ExpImp + democ, data = sanctions_data6, index = c("country", "sanctions_period"), model = "within", effect = "twoways") duplicate couples (time-id) Error in pdim.default(index[[1]], index[[2]]) : I am aware that it means that i have duplicate time periods for the same observations. However the whole observations are not duplicates of each other as they represent

问题 I have code to append ^0 to all the constants in my code so that if you had the string "3x^2+14+2" it would become "3x^2+14^0+2^0" however I am getting a IndexError and I have no idea what I am doing wrong. This is my code: def cleanEquation(equation): equation = ''.join(equation.split()) for i in range(len(equation)): if equation[i].isdigit(): if equation[i-1] != "^": if i == len(equation)-1: equation = equation[:i+1] + '^0' if equation[i+1] == "+" or equation[i+1] == "-": equation =

问题 I have code to append ^0 to all the constants in my code so that if you had the string "3x^2+14+2" it would become "3x^2+14^0+2^0" however I am getting a IndexError and I have no idea what I am doing wrong. This is my code: def cleanEquation(equation): equation = ''.join(equation.split()) for i in range(len(equation)): if equation[i].isdigit(): if equation[i-1] != "^": if i == len(equation)-1: equation = equation[:i+1] + '^0' if equation[i+1] == "+" or equation[i+1] == "-": equation =

问题 I am trying to write a program which calculates formula y=√x*x + 3*x - 500, Interval is [x1;x2] and f.e x1=15, x2=25. I tried to use Exception Handling but it didn't help. And the code I try to use now gives me: ValueError: math domain error import math x1 = int(input("Enter first number:")) x2 = int(input("Enter second number:")) print(" x", " y") for x in range(x1, x2): formula = math.sqrt(x * x + 3 * x - 500) if formula < 0: print("square root cant be negative") print(x, round(formula, 2))

问题 What is this? This is a number of answers about warnings, errors, and notices you might encounter while programming PHP and have no clue how to fix them. This is also a Community Wiki, so everyone is invited to participate adding to and maintaining this list. Why is this? Questions like "Headers already sent" or "Calling a member of a non-object" pop up frequently on Stack Overflow. The root cause of those questions is always the same. So the answers to those questions typically repeat them

问题 I am stuck on something that I have a workaround for, but it bugs me I don't have a direct answer for how to address the issue of using On Error Goto for recurring errors. My question is essentially the same as this one, however the answers provided are alternatives to the OP's overall approach rather than how to handle the specific issue. I've simplified an example below. I am WELL AWARE that there are probably a dozen ways this code could be rewritten to avoid any error -- I am just using

问题 To display errors we need message keys which contains the error messages. I create a new resource bundle named ApplicationError.properties which contain this property: app.error=Error: {0} I try to change this class from struts1 to struts2, but I have a problem with error handling.I have not found the equivalent in struts2 public class MyAction extends Action{ public ActionForward execute(ActionMapping actionMapping, ActionForm actionForm, HttpServletRequest request, HttpServletResponse

问题 To display errors we need message keys which contains the error messages. I create a new resource bundle named ApplicationError.properties which contain this property: app.error=Error: {0} I try to change this class from struts1 to struts2, but I have a problem with error handling.I have not found the equivalent in struts2 public class MyAction extends Action{ public ActionForward execute(ActionMapping actionMapping, ActionForm actionForm, HttpServletRequest request, HttpServletResponse

问题 I tried to validate the construction of a Record with Applicatives and the Either Monad . It works fine. But I can't see all Error Messages. Only the first is visible because the Right Path of the Either Monad ignores them. Here is my code: import Data.Either (either) import Text.Printf (printf) data Record = Record { fieldA :: String , fieldB :: String , fieldC :: String } deriving (Show, Eq) type Err = String setField :: String -> String -> Either Err String setField field value | length

问题 I am building an app in Release, and running on an iPhone 4s. When I click on run, everything works well, my application even runs on the iPhone. But after some times, I have an error from Xcode : "Timed out waiting for app to launch" while my app is still running. How to deal with it? 回答1: Check which provisioning you are using, it seems that ad-hoc provisioning cannot be used for debugging. If your problem is not solve with above instruction then also try these: Stop the app from running in