# Molecular Weights 11

I wouldn’t normally publish a post on such an esoteric topic as this. However, since the idea for it came as a result of a challenge posed by the venerable David Hager, I felt that I could not resist.

And that challenge was as follows: given a list of chemical elements and their respective atomic weights, a formula to determine the weight for a given molecule.

It goes without saying that there are numerous quick and easy online applications which will perform such a calculation. Nevertheless, and however unlikely it may seem, there is still a small probability that this post will reach one or more of the tiny minority who have a practical need for such calculations to be performed within Excel (and, in addition, perhaps without recourse to VBA).

# Advanced Formula Challenge #12: Results and Discussion 5

Last week I set readers the challenge which can be found here.

Such was the number and variety of responses to this challenge that presenting a detailed breakdown of one such solution – as has been the case for all of the first eleven in this series of challenges – would, I feel, be somewhat inappropriate.

For the majority of these challenges, it could be argued that there has been one solution which is indisputably “better” than the rest. Perhaps such an adjudication can also be made here, though to do so would certainly not be a straightforward exercise. What’s more, to pick just one of the many solutions would be to leave the rest – unfairly in my opinion – left on the sidelines.

As such, I would refer the readers to the many solutions in that post and to enjoy dissecting the varied and wonderful constructions therein. And to simply thank all those – Alex, aMareis, Maxim, John Jairo, sam, Jeff, Lori, Ron, Michael, Christian and XLarium – whose excellent contributions led to such a fruitful and inspiring discussion.

There’s evidently still much to be discovered in the world of worksheet formulas!

Another challenge to follow shortly. Watch this space!

# Simultaneous Locating of First and Last Numbers in a String 23

I was initially debating whether to give this post a more pragmatic title, such as “Extracting Phone Numbers from a String”, that being one of the more common practical applications for the techniques outlined here.

However, the extraction of phone numbers (I’m referring here to that type which employs some form of delimiter, e.g. 1-800-12345, and not that which comprises a non-delimited numerical string, e.g. 180012345, there existing already well-documented formula techniques for the extraction of the latter – although of course the set-up given here will work for those as well) is certainly not the only use for this method, and so, in the end, I chose to go with a less restrictive, more theoretical title.

# Extracting Numbers of Set Length Only from Alphanumeric Strings 20

In this post I would like to present a solution to the practical problem of extracting a number of defined length from an alphanumeric string which may contain several numbers of varied lengths.

Indeed, the inspiration behind this post is in part derived from having personally witnessed many such requests on the various Excel forums, most of which involve the extraction of e.g. an account number of fixed length, 6 digits, say, from a longish string containing many other numbers.

As an example, given the following string:

`20/04/15 - VAT Reg: 1234567: Please send 123456 against Order #98765, Customer Code A123XY, £125.00`

we may wish to extract the one occurrence of a 6-digit number (123456) from that string.

# Return Entry Corresponding to Maximum Value Based on Conditions 55

We are often faced with the practical situation in which we need to return the entry from a certain column which corresponds to the maximum numerical value from another column subject to one or more conditions.

For example, from the table below:

we may wish to return the date (column C) which corresponds to the latest version (column B) for a given order number (column A), where by “latest” we mean “largest numerically”.

# Shortest Formula Challenge #3: Results and Discussion 1

Last week I set readers the challenge which can be found here.

This one provoked quite a bit of debate, and not all of it Excel-related! As I already have to several readers, I must again apologize for the lack of realism and statistical know-how inherent in the premise for this challenge, which was evidently constructed more with the required formula-work in mind than with any serious thought to methods in demography.

Still, at least some fascinating and impressive Excel work came out of it all, so perhaps my poor groundwork is somewhat forgiven, at least retrospectively!

# VLOOKUP Across Several Worksheets (2) – Multiple Search Criteria 9

I recently made the post here, in which I presented a solution to the problem of returning a value based upon matching a single criterion in a given column across multiple worksheets.

In this follow-up post I will look at the analogous case in which we are not matching a single criterion, but several. As mentioned in the first instalment, I will look at two solutions to this problem, one in which we make use of an extra “helper” column in each of the relevant worksheets, and one in which we do without such aids.

# VLOOKUP Across Several Worksheets (1) – One Search Criterion 4

Most people with an average level of ability in Excel are perfectly capable of using VLOOKUP when this operation is performed over a range within a single worksheet.

But what happens when we wish to extend our search to multiple worksheets, and so return the first match from whichever sheet happens to be the first which contains our search value(s)?

In this post I will present a solution for such cases in which we have a single criterion to be matched in a given column across multiple worksheets.

In the next instalment (to follow shortly) I will also look at cases in which we are not matching a single criterion, but several. In this situation by far the simplest method is to use an extra “helper” column in each of the relevant worksheets in which we first perform a concatenation of the fields of interest. By doing this we ensure that it is a relatively straightforward case of extending the solution designed for one criterion to work also with multiple criteria.

# Shortest Formula Challenge #2: Results and Discussion 5

Last week I set readers the challenge which can be found here.

5 correct solutions received, courtesy of John Jairo V, GreasySpot, Bill Szysz, James and ChrisBM (who actually missed off a final parenthesis in his formula, though I will be lenient here!). So well done to all!

As to whose was the shortest, excluding the offering from Isai Alvarado, who beat everyone with his 51-character (excluding the equals sign) Google Sheets construction (well done Isai!), that accolade is shared by John and Bill, both of whose solutions came in at 56 characters, which is quite a remarkable coincidence when you consider that each used a completely different construction! So congratulations to John and Bill!

# Unique, Alphabetical List from Several Columns 25

In this post I shall present a method for generating a unique, alphabetical list in a single column from data contained within a contiguous range comprising several columns.

For example, given the dataset below in A2:E5, we will return that list beginning in cell G1:

# Extracting numbers from a string 3: All numbers to individual cells 29

This is the third in a series of discussions on the techniques available for extracting numbers from an alphanumeric string.

In the first instalment in this series (which can be found here) I looked at extracting consecutive numbers which appear at the start of the string, e.g. 123ABC456.

In the second instalment (here) I looked at extracting consecutive numbers which appear at the end of the string, e.g. 123ABC456.

In this post I will demonstrate a technique for extracting all numbers from a string where:

• The string in question consists of a mixture of numbers, letters and special characters
• The numbers may appear anywhere within that string
• Decimals within the string are to be returned as such
• The desired result is to have all numbers returned to separate cells

# Extracting numbers from a string 2: Consecutive numbers at end 3

This is the second in a series of discussions on the techniques available for extracting numbers from an alphanumeric string. In the first instalment in this series (which can be found here) I looked at extracting consecutive numbers which appear at the start of the string, e.g. 123ABC456.

In this post I will concentrate on techniques for extracting numbers from a string where:

• The numbers are consecutive
• The consecutive string of numbers is found at the very end of the string
• The desired result is to have those consecutive numbers returned to a single cell

As previously, for each of the given solutions, we need to test its soundness in two separate cases: firstly, where there are no numbers elsewhere in the string, e.g. ABC456 and secondly, where there are some numbers elsewhere in the string, either at the start, e.g. 123ABC456, or in the middle, e.g. ABC123DEF456.

# Extracting numbers from a string 1: Consecutive numbers at start 8

This is the first in a series of discussions on the techniques available for extracting numbers from an alphanumeric string. Since we often have many different solutions at our disposable for such tasks, I will attempt to present what I feel are the principal candidates and, for each of these set-ups, discuss the merits and potential drawbacks inherent in each.

In the next instalment in this series I shall look at extracting consecutive numbers which appear at the end of the string, e.g. ABC123. In later posts I will deal with cases in which the desired numbers to be extracted are interspersed within the string in groups of one or more, e.g. ABC12DE345-FG6H789, in which case we may be interested in extracting either the number 123456789 into a single cell or each of 12, 345, 6 and 789 into four separate cells.

I shall also consider in future posts cases in which there may be several numbers within a string, though from which we wish to extract perhaps only one (or more) of these numbers, and for which our choice of extraction is based upon one or more criteria. For example, given a string of the form X12-X34-X56-X78-X90 we may wish to develop a technique which extracts the number immediately preceding the fourth occurrence of a hyphen within that string.

# Collating from multiple sheets based on conditions 33

Some of us may be familiar with the standard technique using INDEX, SMALL, etc. which, given a single-column or single-row array, we can use to return a list of only those values which satisfy one or more criteria of our choosing.

In a previous post (see here) I outlined a method which, given a range consisting of more than one column, returned a single column consisting of all non-blank entries from that range. It can easily be verified that the single condition within this formula (i.e. that the entry be non-blank) can be extended to multiple criteria and so, effectively, we now have at our disposable the means with which to generate single-column lists from both one- and two-dimensional arrays.

But can we go one further yet again? “Three-dimensional” is the collective term often applied to those formulas in Excel which are capable of operating over not just single columns or rows, nor yet ranges consisting of multiple columns or rows (two-dimensional), but which also function effectively over multiple worksheets.

# Advanced Formula Challenge #7: Results and Discussion 1

Last week I set readers the challenge which can be found here.

This is a trickier problem than it at first appears, and indeed there are several pitfalls which prevent us from using more “standard” techniques to arrive at a solution.

Perhaps the two main (hidden) obstacles, which were not immediately obvious from the examples I gave, are, firstly, the fact that we are prevented from using a construction involving a SEARCH-approach (e.g. by locating occurrences of each substring of the four types *????*, †????*, *????† and †????†, as John Jairo V attempted), since this of course presumes that there is only one occurrence of each of those substring types within our string, a presumption which cannot be made.

# Advanced Formula Challenge #4: Results and Discussion Reply

Last week I set readers the challenge which can be found here.

This one turns out to be a good deal more complex than it at first appears, and so perhaps not surprisingly no correct results were received..

GreasySpot at first thought that Advanced Filter would be a viable solution, but quickly realised that it wasn’t actually appropriate here. Besides, as I mentioned, the idea of this (and of all these challenges in fact) is to try to achieve the results using worksheet formulas alone.

So how can we achieve our desired results?