Simplifying IF AND OR Functions with The JayTray

Transcription

1 Simplifying IF AND OR Functions with The JayTray JayTray THEJAYTRAY.IE BLOG.THEJAYTRAY.COM

2 Table of Contents Introduction... 1 Objective of Book... 1 Version of Excel... 1 Using Wizards vs Typing Functions... 1 Logical Functions... 2 File Layout... 3 Basic Logical Test... 4 IF... 5 AND... 7 IF AND... 8 OR... 9 IF OR Next Steps & Notes Note IF COUNTIF Logical Test About The JayTray... 15

3 Introduction Objective of Book This e-book is targeted at people who have at least a basic knowledge of Excel, the layout and formulas. The aim of this e-book is to introduce you to some of the Logical functions in Excel. These functions include LOGICAL TESTS IF AND OR Each function will be explained individually and then examples will be given on how you can further use these and combine them for different purposes. There is an assumption that you understand at least the basics of Excel. Version of Excel This e-book has been created using Excel Excel 2010 and 2007 use very similar steps, although icons or colours may look different. For prior versions of Excel, you will have to use the Insert Function, or you can enter the formula manually. Using Wizards vs Typing Functions Personally, my preference is to type a formula, but I will also show the screenshots to create a formula using the wizard. Both ways work and will return the same result, it is up to you to decide on your own preference. When typing formulas, I will use uppercase throughout this e-book, but these formulas are not case sensitive in Excel. TheJayTray.ie Page 1

4 Logical Functions The Logical Functions can be found in the Function Library section of the FORMULAS tab on your menu bar. Clicking on this button shows a list of all the Logical Functions. You can select your function from this list by clicking on it. You can also show a list of all Logical Functions by clicking on the formula bar. button to the left of the From the Or Select a category list, select Logical This also lists all Logical Functions. TheJayTray.ie Page 2

5 File Layout For my demonstration, and your practice create a file similar to the one below. Cells A3 to A8 lists our students names, and B3 to F8 give the results of each subject. We will enter our formula in column G. We will assume for the sake of demonstration that the pass rate is 50%. Ready to start on the first of our Logical functions? Let s start with the basic logic test first TheJayTray.ie Page 3

6 Basic Logical Test As we go through the various logical functions, you will notice that some require a logical test or logical value. What is a logical test? It is a test of logic that will either result in a true or false (yes/no, pass/fail, etc.) value. In its simplest form, let s test if each student s English result is greater or equal than the pass mark of 50. Starting in cell G3, enter =B3>=50. That is a logical test, is 48 greater than or equal to 50? That test will result in either a True or False reply. Copy the formula down for the remaining students. So far, this isn t strictly speaking a calculation, just a test. If the statement is false, then the result of our test if FALSE and, if the value of the test is true then the result is TRUE. What is the point of knowing this? The logical test is the foundation of the Logical Functions. Later we will be telling Excel what to do based on whether these statements are true or false. Without understanding the logical test/statement on its own will make the next formula a bit more difficult than they actually are. TheJayTray.ie Page 4

7 IF The IF function Checks whether a condition is met, and returns one value if TRUE, and another value if FALSE. The condition here is our logical test. The syntax is =IF(Logical_test, Value_if_true, Value_if_false) Logical_test = This is our logical test, in our case is the student s mark greater than or equal to the pass rate? Value_if_true = If the student s mark is greater than or equal to the pass mark, what do we want the function to do? If we want to say PASS for example, then we would enter that (make sure to enter between double apostrophes). Value_if_false = What do you want the function to do if the logical test is false? So, if the student s result is not greater than or equal to the pass mark, what do you want the function to do? We want to test to see if the student s English result is greater than or equal to the pass mark (50) then we want to say PASS, or else we want to say FAIL. When I first learned about IF functions, I learned it (and still think of it this way) as IF-THEN-ELSE. IF the result is greater than or equal to 50 THEN say PASS or ELSE say FAIL. TheJayTray.ie Page 5

8 The completed IF function is =IF(B3>=50, PASS, FAIL ). Note the commas separate the different parts of the functions syntax. Remember to enter the text PASS and FAIL between double apostrophes. Copy this formula down for the remaining students. Change the formula to test other subjects, or change the pass rate. Why not enter the pass rate in a table outside the above table and refer to that cell instead of stating 50 in the function. TheJayTray.ie Page 6

9 AND The AND function Checks whether all arguments are TRUE, and returns TRUE if all arguments are TRUE. Previously we used one logical test, now we are going to use two. The above box shows you that you can enter Logical1 and Logical2 tests or arguments. Once you enter the second argument, then another field for Logical3 appears and so on. We are going to test if the English AND French results are greater than or equal to the pass mark of 50. This returns TRUE or FALSE depending on if ALL arguments are true or false. If one argument is true and one argument is false, then the function will return FALSE, because not all the arguments are true. This is an important distinction to note, if you want to test where all arguments are TRUE then you can use the AND function in this way. Even if you had 5 arguments and only 1 of these arguments were false, then the result of your whole function will be FALSE, because not all arguments are true. When this makes sense, you can proceed to using the AND within and IF function. TheJayTray.ie Page 7

10 IF AND The IF AND function is the same as an IF function, but the difference here is that your logical_test is now going to be an AND function. Let s breakdown this IF AND function: Logical_test = This is an AND function that has two logical tests o Logical1 = Is the English result greater than or equal to 50 o Logical2 = Is the French result greater than or equal to 50 Value_if_true = If the AND function results in true, then we want the function to say PASS Value_if_false = if the AND function results in false, then we want the function to say FAIL. Note the brackets around the logical tests within the AND function and also the commas that separate the different parts of each function. TheJayTray.ie Page 8

11 OR The OR function Checks whether any of the arguments are TRUE, and returns TRUE or FALSE. Returns FALSE only if all arguments are FALSE. This is similar in use to the AND function, but where the AND function returned TRUE only if all arguments are true, the OR function will return TRUE if any of the arguments are true. Again, change the results or pass marks if you want to test the formula. The OR function will only return FALSE if all the arguments are false. Next we will use the OR together with an IF function. TheJayTray.ie Page 9

12 IF OR The IF OR function, again, is the same as an IF function, but the difference here is that your logical_test is now going to be an OR function. Let s breakdown this IF AND function: Logical_test = This is an OR function that has two logical tests o Logical1 = Is the English result greater than or equal to 50 o Logical2 = Is the French result greater than or equal to 50 Value_if_true = If the OR function results in true, then we want the function to say PASS Value_if_false = if the OR function results in false, then we want the function to say FAIL. As with the IF AND function, note the brackets around the logical tests within the OR function and also the commas that separate the different parts of each function. TheJayTray.ie Page 10

13 Next Steps & Notes If you understand the IF, AND and OR functions then you already have an understanding of logical tests that can help you understand further logical tests, but also you now have functions that can be used with others to make some useful, time saving functions. Note I see people getting confused sometimes with the AND & OR functions within IF functions. In most cases, the reason for this is not understanding exactly what the AND & OR functions mean. The AND function will return TRUE only if ALL arguments are true. If even one out of many arguments are false, then the whole function will result in FALSE. The OR function will return TRUE if ANY of the arguments are true. If one or all arguments are true, the function will result in TRUE. The function will only result in FALSE if all the arguments are false. In a lot of cases users requirements aren t met by using either IF, AND or OR in their basic form. Here are two examples of common cases I am asked about. If you wanted to test for example if at least 2 of our 5 arguments were true, then you could combine COUNTIF with IF and logical tests which we will do in the section titled IF COUNTIF Logical Test. If you wanted to run several logical tests quickly, without entering each logical argument, you can use an array formula. We will go through this in the IF AND ARRAY. TheJayTray.ie Page 11

14 IF COUNTIF Logical Test I ve changed the text in G2 to say Did the student pass at least 2 exams?. We will use IF, COUNTIF and logical tests to answer the question in G2. We will first use an IF statement. The logical_test is going to be made up of a COUNTIF function, which will count how many times the student s scores are greater than or equal to 50 (how many subjects the student passed) and tests if that is greater than or equal to 2. The Value_if_true will be YES if the student passed at least 2 subjects. The Value_if_false will be NO if the student has not passed at least 2 subjects. Note the brackets, commas and double apostrophes, their correct use is very important for this formula to work. If you find this hard to understand or create yourself initially, then try it in these steps: Create a COUNTIF formula that counts how many subjects the student passed. Make this a logical function by adding >=2 at the end. You should get TRUE where the COUNTIF resulted in at least 2 Make this an IF function by adding IF( just before the COUNTIF function and then completing the Value_if_true and Value_if_false at the end to complete the function. TheJayTray.ie Page 12

15 IF AND ARRAY I have changed the text in G2 to Did the student pass ALL exams?. Below that I have entered an IF AND formula for each student testing if all their results are greater than or equal to the pass mark, 50. As you can see, I have 5 logical arguments in my AND function. This didn t take long to build, but if the number of arguments kept increasing this can be an unnecessarily long looking formula. If you are feeling a bit adventurous you can read on and see how to use Arrays with the IF AND functions. An array for our purposes here is basically a collection of items. We will have an array that will be made up of each subject result for the student. The array B3:F3 will be all the results for Alan, and we will test the array to see if it is greater than or equal to 50. It will test B3 first, the C3, then D3, then E3 and finally F3 against 50. TheJayTray.ie Page 13

16 The formula as created by you will at first look like this: Instead of checking B3 against 50, we are now highlighting from B3 to F3. Note that this results in an error message, that is because the function makes no sense at this point. We have not yet changed this formula to an array formula. To make this an array formula, at the end of the formula press Ctrl+Shift+Enter/Return (CSE). You will see then that the curly braces are added to the start and end of the formula. You do not type in these brackets yourself though. When you see these in cases like this, it means that there is an array. Now, our array formula will compare B3 first to 50, then C3 to 50 and so on, without us having to enter each individual logical argument ourselves. The IF OR function can also be made an array formula and used in this way too. TheJayTray.ie Page 14

17 About The JayTray Written by a past client Jay is an experienced and enthusiastic effectiveness and performance consultant with extensive coaching, mentoring and training skills. He has a proven ability to analyse performance and identify effective solutions for clients to help them meet their objectives. Jay has trained in advanced improvement techniques such as: Lean, Six sigma, Mistake proofing, and 5s He has extensive experience applying these techniques in his own work in the multi-national, professional services and manufacturing sectors. He has also worked privately with organisations, entrepreneurs and private individuals, helping them to enhance their personal and technological effectiveness. Jay recognises that each client s requirements are unique. He uses his knowledge, skills and passion for research and innovation to take a problem focused approach to learning and development. This allows him to tailor his training to meet the specific requirements of each client. This results in training which consistently exceeds the expectations of his clients, in the most time and cost effective manner possible. People call Jay when they need to improve their personal or technological effectiveness. Because the training is designed to meet the client s specific needs, they will benefit from: Training in a wider range of areas than is usually offered on a typical course Avoiding training which is of no relevance to them Having their training needs met by one course rather than having to take a multitude of courses Jay typically works with clients to help them: Learn from the basics to advanced levels of computers including; , Facebook, games, photo editing, video and sound, Office and a range of applications Systems based training, Identify and implement smarter and more effective ways of doing things, Effective process management e.g., reduce waste and rework, and make processes flow smoother. Staff training Workplace organization where time is spent searching; people are inundated with paperwork or ; mistakes are repeatedly being made; and where people think a lot of time is being spent on a task Jay can look at ways to reduce that time TheJayTray.ie Page 15