Evaluating process: Difference between revisions

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You should remember your order of operations:
You should remember your order of operations:


In mathematics and computer programming, the order of operations (or operator precedence) is a collection of rules that reflect conventions about which procedures to perform first in order to evaluate a given mathematical expression.<ref>https://en.wikipedia.org/wiki/Order_of_operations</ref> The mathematical order of operation is: PEMDAS (
In mathematics and computer programming, the order of operations (or operator precedence) is a collection of rules that reflect conventions about which procedures to perform first in order to evaluate a given mathematical expression.<ref>https://en.wikipedia.org/wiki/Order_of_operations</ref> The mathematical order of operation is: PEMDAS (Parentheses, Exponents, Multiplication, Division, Addition, Subtraction).


== How to evaluate a process ==  
== How to evaluate a process ==  
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=== Example ===
=== Example ===


Imagine you are writing a simple computer program which must output the winner of a game. A winner is determined whichever score is higher.  The input is two scores. The output must be only one of the scores below:
Imagine you are writing a simple computer program which must output the winner of a game. A winner is determined by the highest numerical score (int).  The input is two scores. The output must be only one of the scores below:


# The first score is the winner
# The first score is the winner
Line 21: Line 21:
# There is a tie
# There is a tie


<syntaxhighlight lang="python" linenumbers="true">
<syntaxhighlight lang="python" line>


def whoIsTheWinner(score1, score2):
def whoIsTheWinner(score1, score2):
     if(score1 > score2):
     if score1 > score2:
         winner = "The first score is the winner"
         winner = "The first score is the winner"
     elif(score2 > score1):
     elif score2 > score1:
         winner = "The second score is the winner"
         winner = "The second score is the winner"
     else:
     else:
         winner = "There is a tie"
         winner = "There is a tie"
    return winner
</syntaxhighlight>
</syntaxhighlight>


If we were to evaluate this process, we would ask ourselves
If we were to evaluate this process, we would stop at '''each line of execution''' the value of each variable (score1 and score2). We would then ask ourselves:


== Do you understand this? ==
# If score1 is higher than score2, would the program output score1 is the winner?
# If score2 is higher than score1, would the program output score2 is the winner?
# If both scores are the same, would the program output there is a tie?


Other Questions to code:
# If John is a bachelor, then he is male. John is male. Therefore, John is a bachelor.
# If today is Monday, then I will attend cooking class today.
# Either the current pope is married or he is a divorcé.


== Standards ==  
== Standards ==  

Latest revision as of 18:11, 2 September 2018

Evaluating process[1]

You must evaluate if the sequence of activities (or instructions) will result in the required outcomes. This evaluation can be logical, arithmetic, or both.

A common scenario is evaluating the order of conditionals. You must become very good at tracing conditional expressions.

You should remember your order of operations:

In mathematics and computer programming, the order of operations (or operator precedence) is a collection of rules that reflect conventions about which procedures to perform first in order to evaluate a given mathematical expression.[2] The mathematical order of operation is: PEMDAS (Parentheses, Exponents, Multiplication, Division, Addition, Subtraction).

How to evaluate a process[edit]

Use a step-by-step process and trace the value of a variable or value. Ask yourself, at each step in the process, what is the current value or state of a variable. Let's look at some examples.

Example[edit]

Imagine you are writing a simple computer program which must output the winner of a game. A winner is determined by the highest numerical score (int). The input is two scores. The output must be only one of the scores below:

  1. The first score is the winner
  2. The second score is the winner
  3. There is a tie
def whoIsTheWinner(score1, score2):
    if score1 > score2:
        winner = "The first score is the winner"
    elif score2 > score1:
        winner = "The second score is the winner"
    else:
        winner = "There is a tie"
    return winner

If we were to evaluate this process, we would stop at each line of execution the value of each variable (score1 and score2). We would then ask ourselves:

  1. If score1 is higher than score2, would the program output score1 is the winner?
  2. If score2 is higher than score1, would the program output score2 is the winner?
  3. If both scores are the same, would the program output there is a tie?

Other Questions to code:

  1. If John is a bachelor, then he is male. John is male. Therefore, John is a bachelor.
  2. If today is Monday, then I will attend cooking class today.
  3. Either the current pope is married or he is a divorcé.

Standards[edit]

  • Evaluate whether the order in which activities are undertaken will result in the required outcome.

References[edit]