# (Excel examples for Beginners)

In this end-to-end excel example, you will learn – Excel formula for Beginners – How to Sum by weekday in Excel.

### Generic formula

`=SUMPRODUCT((WEEKDAY(dates)=day_num)*values)`

### Explanation

To sum data by weekday (i.e. sum by Mondays, Tuesdays, Wednesdays, etc.), you can use the SUMPRODUCT function together with the WEEKDAY function.

In the example shown, the formula in H4 is:

`=SUMPRODUCT((WEEKDAY(dates,2)=G4)*amts)`

### How this formula works

You might wonder why we aren’t using the SUMIF or SUMIFS function? These appear to be an obvious way to sum by the days of the week. However, without adding a helper column with a weekday value, there is no way to create a criteria for SUMIF that takes into account the weekday.

Instead, we use the handy SUMPRODUCT function, which handles arrays gracefully without the need to use Control + Shift + Enter.

We are using SUMPRODUCT with just one argument, which consists of this expression:

`(WEEKDAY(dates,2)=G4)*amts`

Working from the inside out, the WEEKDAY function is configured with the optional argument 2, which causes it to return numbers 1-7 for the days Monday-Sunday, respectively. This is not necessary, but it makes it easier to list the days in order and pick up the numbers in column G in sequence.

WEEKDAY evaluates each value in the named range “dates” and returns a number. The result is an array like this:

{3;5;3;1;2;2;4;2}

The numbers returned by WEEKDAY are then compared to the value in G4, which is 1.

{3;5;3;1;2;2;4;2}=1

The result is an array of TRUE/FALSE values.

{FALSE;FALSE;FALSE;TRUE;FALSE;FALSE;FALSE;FALSE}

Next, this array is multiplied by the values in the named range “amts”.  SUMPRODUCT only works with numbers (not text or booleans) but math operations automatically coerce the TRUE/FALSE values to one’s and zeros, so we have:

{0;0;0;1;0;0;0;0}*{100;250;75;275;250;100;300;125}

Which yields:

{0;0;0;275;0;0;0;0}

With just this single array to process, SUMPRODUCT sums the items and returns the result.

# Personal Career & Learning Guide for Data Analyst, Data Engineer and Data Scientist

## Applied Machine Learning & Data Science Projects and Coding Recipes for Beginners

A list of FREE programming examples together with eTutorials & eBooks @ SETScholars

# Projects and Coding Recipes, eTutorials and eBooks: The best All-in-One resources for Data Analyst, Data Scientist, Machine Learning Engineer and Software Developer

Topics included: Classification, Clustering, Regression, Forecasting, Algorithms, Data Structures, Data Analytics & Data Science, Deep Learning, Machine Learning, Programming Languages and Software Tools & Packages.
(Discount is valid for limited time only)

`Disclaimer: The information and code presented within this recipe/tutorial is only for educational and coaching purposes for beginners and developers. Anyone can practice and apply the recipe/tutorial presented here, but the reader is taking full responsibility for his/her actions. The author (content curator) of this recipe (code / program) has made every effort to ensure the accuracy of the information was correct at time of publication. The author (content curator) does not assume and hereby disclaims any liability to any party for any loss, damage, or disruption caused by errors or omissions, whether such errors or omissions result from accident, negligence, or any other cause. The information presented here could also be found in public knowledge domains.`

# Learn by Coding: v-Tutorials on Applied Machine Learning and Data Science for Beginners

Please do not waste your valuable time by watching videos, rather use end-to-end (Python and R) recipes from Professional Data Scientists to practice coding, and land the most demandable jobs in the fields of Predictive analytics & AI (Machine Learning and Data Science).

The objective is to guide the developers & analysts to “Learn how to Code” for Applied AI using end-to-end coding solutions, and unlock the world of opportunities!

Excel formula for Beginners – How to find Max value on given weekday in Excel

Excel formula for Beginners – How to Count numbers that begin with in Excel

Excel formula for Beginners – How to Subtotal by category in Excel