Why mysql gives result with postfix zeros

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By : Agara Bent

Date : November 29 2020, 09:01 AM

seems to work fine Columnname CallDuration Values like 35,59,59 etc no zero or null at present. , you can use ROUND in this query like

code :

SELECT ROUND(AVG(CallDuration)),
   SUM(CallDuration)/COUNT(*) AS `Time` 
   FROM cdr;

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Why won't Perl let me chain a postfix loop from a postfix comparison?

By : user1272262

Date : March 29 2020, 07:55 AM

wish helps you You can only have one postfix operation per statement. But you can do what you want (sorta) by using a do block, e.g.

code :

do { $foo++ if $condition } for ( 1..10 );

for( 1..10 ) { $foo++ if $condition }

INSERT array into mysql table (only zeros as result)

By : Joao Luis Orgal

Date : March 29 2020, 07:55 AM

around this issue Inside each item in your array $ar there is another array.
So your query should be:

code :

$sql = " INSERT INTO table(yo) VALUES('".$ar[$i]['ciao']."') " ;

Converting from Infix to Postfix and evaluating Postfix notation

By : WarpSpeed

Date : March 29 2020, 07:55 AM

it fixes the issue One problem is your are storing values in s as a char with storage of 1 byte per element and then attempt to push integers into s with:

code :

pushit (int ele) {      /* Function for PUSH operation */
    s[++top] = ele;
}

op2=popit();
op1=popit();

int popit(){                      /* Function for POP operation */
return(s[top--]);
}

popit.c:8:1: warning: return type defaults to ‘int’
popit.c:32:1: warning: return type defaults to ‘int’
popit.c:41:1: warning: return type defaults to ‘int’

PostFix Evaluation Result Error

By : LineByLine

Date : March 29 2020, 07:55 AM

To fix this issue I dont have a computer at hand, only an old school paper and pen, my phone and some knowledge about the shunting-yard algorithm.
I think your error is this (only tested on paper):

code :

evaluateStack.push(evaluateStack.pop() + evaluateStack.pop());

//Don't change pop order here!
int righthand = evaluateStack.pop();
int lefthand = evaluateStack.pop();

evaluateStack.push(lefthand + righthand);

public static int postFixEvaluation(int[] numValues, String postfix){
    Stack<Integer> evaluateStack = new Stack<Integer>();
    char[] chars = postfix.toCharArray();
    int length = chars.length;
    int currentNumValue =0;
    int currentLocation =0;

    for (int i = 0; i < length; i++){
        char currentChar = chars[i];

        //checks to see if character is a letter
        if (Character.isLetter(currentChar)){
            //replace all letters with values 
            currentLocation = charToNum(currentChar);//this retrieves the location of specific letter
            currentNumValue = (numValues[currentLocation]);//retrieves the value of that location
            evaluateStack.push(currentNumValue);//get the number value of that variable and push it on stack
            System.out.println(Arrays.toString(evaluateStack.toArray()));//prints out stack elements 
        }


        //checks if character is an operator 
        if (isOperator(currentChar)){
            int righthand = evaluateStack.pop();
            int lefthand = evaluateStack.pop();
            switch (currentChar){
            //switches evaluation according to operator 
                case '+': evaluateStack.push(lefthand + righthand); break;
                case '*': evaluateStack.push(lefthand * righthand); break;
                case '-': evaluateStack.push(lefthand - righthand); break;
                case '/': evaluateStack.push(lefthand / righthand); break;
            }
        }
    }
    if (!evaluateStack.isEmpty()){ //as long as the stack is not empty
        return evaluateStack.pop();//returns the result
    } else {
        return 0; //if it is empty returns zero 
    }
}

Convert a Postfix expression to infix and calculate the postfix and give the answer

By : jdog

Date : March 29 2020, 07:55 AM

I think the issue was by ths following , I have been working on this program to take in a postfix expression, calculate and print out its answer, and also convert it to infix expression. I have gotten the calculation part of it to work. For instance, if I enter 2 2 +(accounting for the spacing) it gives me 4. However, for the infix part of it it prints out 2+. I then tried it just doing it without any spacing. I put in 22+. The postfix did not work, but the infix printed out properly. So I am not sure how to fix this part of it. Here is my code.

code :

if (isOperator(ch))
{
    TreeNode rightNode = nodes.pop();
    TreeNode leftNode = nodes.pop();
    nodes.push(new TreeNode(leftNode, ch, rightNode));
}
else
{
    nodes.add(new TreeNode(null, ch, null));
}

if (isOperator(ch))
{
    TreeNode rightNode = nodes.pop();
    TreeNode leftNode = nodes.pop();
    nodes.push(new TreeNode(leftNode, ch, rightNode));
}
else if (!Character.isWhitespace(ch))
{
    nodes.add(new TreeNode(null, ch, null));
}