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Python helper function scope

python,function,scope,local-variables
So, I have a whole bunch of things doing basically the same thing with only a slight change in input. Perfect candidate to be function'd out and called each time with different parameters, right? Apparently, python thinks I'm wrong. So, here's a boiled-down version of my problem def main(): x...

Local variables on stack

c,stack,local-variables
To understand the stack frame concept, I wrote a little program for my own. First I will show you the code, a little sketch about it and then I will present my question: So, the program: int check_pw(char *password){ int valid = 0; char buffer[10]; strcpy(buffer, password); if(strcmp(buffer, "a") ==...

why can't I return local variable?

function,opencv,return,local-variables
I don't know why c++'s rule says that I can't return local variable? this simple "max" function totally has no problem; int max(int a,int b) { int maxnum; if(a>b)maxnum= a; else maxnum= b; return maxnum; } int main( int argc, char** argv ) { cout<<max(10,30); system("PAUSE"); return 0; } but,...

Identify the arguments, parameters, local variables and global variables used in the following code?

javascript,parameters,arguments,global-variables,local-variables
The code is: var x = 32; var y = 44; var radius = 5; var centerX = 0; var centerY = 0; var width = 600; var height = 400; function setup(width, height) { centerX = width/2; centerY = height/2; } function computeDistance(x1, y1, x2, y2) { var dx...

Why a variable defined global is undefined? [duplicate]

javascript,global-variables,local-variables,hoisting
This question already has an answer here: 'Hoisted' JavaScript Variables 4 answers Hi guys here I have a simple function and a global variable. My question is why myname = "glabol" is undefined and not the string "global" var myname = "global"; // global variable function func() { alert(myname);...

Global variable returned as undefined when it is again declared locally in a block and referred before the declaration in the block. [duplicate]

javascript,global-variables,local-variables
This question already has an answer here: Why does local variable kill my global variable? 6 answers var a = 10; function example(){ alert(a); var a = 5; } example(); This code alerts undefined. My question is why variable a is alerting "undefined" instead of returning global variable's value....

What does “local variables at the outermost scope of the function may not use the same name as any parameter” mean?

c++,parameters,scope,local-variables
I have been reading the C++ primer 5th edition. In the third paragraph of Function Parameter List of Chapter 6.1 . It writes "Moreover, local variables at the outermost scope of the function may not use the same name as any parameter". What does it mean? I am not native...

How could I use these local variables for object position in my main function?

c++,vector,global-variables,computer-vision,local-variables
I'm using some computer vision code in c++ that tracks an object after you draw a bounding box around it, and it can track multiple objects with multiple bounding boxes. In one of the header files there is a function that processes the frame and defines the objects center pixel...

C++ Same name local variables keeping values between loops [closed]

c++,loops,for-loop,local-variables
I have the following 2 loops in my C++ code: for (int hcount = 0; hcount < height; hcount++) { for (count = 0; count < width; count++) { cout << character; } cout << endl; } cout << endl; for (int hcount = 0; hcount < height; hcount++); {...

How to dynamically define local variables [duplicate]

ruby,metaprogramming,local-variables
This question already has an answer here: How to dynamically create a local variable? 1 answer I want to loop through an array of one word strings and turn them into instances of a class. Something like this: names_array = ["jack", "james","jim"] names_array.each { |name| name = Person.new }...

java - How to retrieve anything inside method

java,methods,constructor,local-variables,bcel
From what i know, java cannot retrieve anything inside method. so i using option -g or -g:vars in javac. for e.g : class Test { int a=0; void method(boolean boo){ String b; try { new Thread().sleep(1000); } catch(InterruptedException e){} JOptionPane.showMessageDialog(null,"test"); BufferedImage image=ImageIO.read(new File("C:\\file.png")); } } So, i use BCEL to...

Java Garbage collection against Local and Global variable with Thread Safe

java,garbage-collection,thread-safety,global-variables,local-variables
Which of the below snip of code is more Garbage Collection efficient in terms of TIME Class Test{...} Local Variable private void function(){ Test test = new Test(); .... } Global Variable Test test = null; private void function(){ if(test == null){ test = new Test(); } } Let assume...

Get value from string representing local variable [duplicate]

ruby,local-variables
This question already has an answer here: Is there a 'variable_get' method? If not, how can I create my own? 2 answers I have a local variable name as a string, and need to get its value. variable = 22 "variable".to_variable? How can I get the value 22 form...

C - Global vs Local multidimensional array

c,multidimensional-array,global-variables,local-variables
When I execute this code (gcc compiled): #include <stdio.h> int main() { int table[1005][1005]; return 0; } it stops working, but when I change it to: #include <stdio.h> int table[1005][1005]; int main() { return 0; } it works just fine.. Why is this concretely happening? Does global variables get more...