Given a list, I would like to make a list of cumulative values:
I have created a formula which works =MAKEARRAY(1;5;LAMBDA(r;c;SUM(INDEX(F5:J5;1;1):INDEX(F5:J5;1;c)))).
However, I realize that by wrapping it with LET the formula =LET(ps; F5:J5; MAKEARRAY(1;COLUMNS(ps);LAMBDA(r;c;SUM(INDEX(ps;1;1):INDEX(ps;1;c))))) returns a list of #VALUE.
Does anyone know the reason?
Additionally, does anyone have a better idea to make such a cumulative list by Excel formulas (my solution is not optimal)? If we don't use the LAMBDA function and the helper functions, that will be even better.
When using a range in LET it is no longer stored as a range, but as an array in memory.
The position in the sheet is no longer relevant. But when you use INDEX(start,1,1):INDEX(end,1,1) references, the position is relevant, because where in the sheet would for instance start be, and where would end be? By using LET you tell Excel to no longer store it's position and you therefore can use the individual values in each "range", but you can't refer to anything in between the two.
Instead you could better use SCAN for this;
=SCAN(0,SEQUENCE(1,5),LAMBDA(a,b,a+b))
Or =SCAN(0,F5:J5,LAMBDA(a,b,a+b))
Related
Alright this should be a simple one.
I apologize in case it has been already solved, but I can only find posts related to solving this issue with programming languages and not specifically to EXCEL.
Furthermore, I could find posts that address a sub-problem of my question (e.g. regarding limitation of certain EXCEL functions) and should solve/invalidate my request but maybe, just maybe, there is a workaround.
Problem statement:
I want to calculate the minimum value for each column in an EXCEL matrix. Simply enough, I want to input a 2D array (mxn matrix) in a function and output an array with dimension 1xm where each item is the minimum value MIN(nj) of each nj column.
However, I want to solve this with specific constraints:
Avoid using VBA and other non-function scripting: that I could devise myself;
All in one function: what I want to achieve here is to have one and one function only, not split the problem into multiple passages (such as for example copypasting a MIN() function below each column, that wouldn't do it);
The result should be a transposable array (which is already ok, I assume);
Where I am stranded with my solution so far:
The main issue here is that any function I am trying to use takes the entire matrix as a single array input and would calculate the MIN() of the entire matrix, not each column. My current (not working) function for an exemplary 4x4 matrix in range A1:D4 would be as below (the part in bold is where it is clearly not working):
=MIN(INDEX(A1:D4,SEQUENCE(4,4,1,1)))
which ofc does not work, because INDEX() does probably not "understand" SEQUENCE() as an array of items to take into account. Another, not working, way of solving this is to input a series of ranges (A1:A4;B1:B4;C1:C4;D1:D4) so that INDEX() "understands" the ranges as single columns, but ofc does not know and I do not know sincerely how to formulate that. I could use INDIRECT() in some way to reference the array of ranges, but do not know how and could find a way by searching online.
Fundamental question is: can a function, which works with single arrays, also work with multiple arrays? Basically, I do not know how to communicate an EXCEL array formula, that each batch of data I am inputting is a single array and must be evaluated separately (this is very easily solved with for() cycles, I know).
Many thanks for any suggestion and any workaround, any function and solution works as longs as it fits in the constrains defined above (maybe a LAMBA() function? don't know).
This is ofc a simplification of a way more complex problem (I am trying to calculate the annual mean temperature evolution for a specific location by finding the value - for each year from 1950 to 2021 - that is associated to the lat/lon coordinates that are the nearest to the one of the location inputted, given a netCDF-imported grid of time-arrayed data; the MIN() function is used to selected the nearest location, which is then used, via INDEX() to find temp data). I need to do this in one hit (meaning just pasting the function, which evaluates a matrix of data that is referenced by a fixed range), so that I can just use it modularly for other data sets. I already have a working solution, which is "elegant"* enough, but not "elegant"* as the one I could develop solving this issue.
*where "elegant"= it saves me one click every time for 1000+ datasets when applying the function.
If I understand your problem correct then this should solve it:
=BYCOL(A1:D4,LAMBDA(d,MIN(d)))
Ever since I learnt that Excel is now Turing-complete, I understood that I can now "program" Excel using exclusively formulas, therefore excluding any use of VBA whatsoever.
I do not know if my conclusion is right or wrong. In reality, I do not mind.
However, to my satisfaction, I have been able to "program" the two most basic structures of program flow inside formulas: 1- branching the control flow (using an IF function has no secrets in excel) and 2- loops (FOR, WHILE, UNTIL loops).
Let me explain a little more in detail my findings. (Remark: because I am using a Spanish version of Excel 365, the field separator in formulas is the semicolon (";") instead of the comma (",").
A- Acumulator in a FOR loop
B- Factorial (using product)
C- WHILE loop
D-UNTIL loop
E- The notion of INTERNAL/EXTERNAL SCOPE
And now, the time of my question has arrived:
I want to use a formula that is really an array of formulas
I want to use an accumulator for the first number in the "tuple" whereas I want a factorial for the second number in the tuple. And all this using a single excel formula. I think I am not very far away from succeeding.
The REDUCE function accepts a LET function that contains 2 LAMBDAS instead of a single LAMBDA function. Until here, everything is perfect. However, the LET function seems to return only a "single" function instead of a tuple of functions
I can return (in the picture) function "x" or function "y" but not the tuple (x,y).
I have tried to use HSTACK(x,y), but it does not seem to work.
I am aware that this is a complex question, but I've done my best to make myself understood.
Can anybody give me any clues as to how I could solve my problem?
Very nice question.
I noticed that in your attempts you have given REDUCE() a single constant value in the 1st parameter. Funny enough, the documentation nowhere states you can't give values in array-format. Hence you could use the 1st parameter to give all the constants in (your case; horizontal) array-format, and while you loop through the array of the 2nd parameter you can apply the different types of logic using CHOOSE():
=REDUCE({0,1},SEQUENCE(5),LAMBDA(a,b,CHOOSE({1,2},a+b,a*b)))
This way you have a single REDUCE() function which internal processes will update the given constants from the 1st parameter in array-form. You can now start stacking multiple functions horizontally and input an array of constants, for example:
=REDUCE({0,1,100},SEQUENCE(5),LAMBDA(a,b,CHOOSE({1,2,3},a+b,a*b,a/b)))
I suppose you'd have to use {0\1} and {1\2} like I'd have to in my Dutch version of Excel.
Given your accumulator:
Formula in A1:
=REDUCE(F1:G1,SEQUENCE(F3),LAMBDA(a,b,CHOOSE({1,2},a+b,a*b)))
I'm trying to make my monthly transaction spreadsheet less work-intensive but I'm running up against problems outputting my category lookups as an array. Right now I have a table with all my monthly transactions and I want to create another table with monthly running totals. What I've been doing is manually summing each entry from each category, but I'd love to automate the process. Here's what I have:
=SUM(INDEX(Transactions[Out], N(IF(1,MATCH(I12,Transactions[Category],FALSE)))))
I've also tried using AGGREGATE in place of SUM but it still only returns the first value in the category. The N(IF()) was supposed to force INDEX to return all the matches as an array, but it's not working. I found that trick online, with no explanation of why it works, so I really don't know how to fix it. Any ideas?
Just in case anyone ever looks at this thread in the future, I was able to find a simpler solution to my problem once I implemented the Transactions[Category]=I12 method. SUM, itself will take an array as an argument, so all I had to do was form an array of the values I wanted to keep from Transactions[Out] range. I did this by adjusting the method Ron described above, but instead of using 1/(Transactions[Category]=I12 I used 1/IF(Transactions[Category]=I12, 1,1000) and surrounded that by a FLOOR(*resulting array*, .01) which rounded all the thousandth's down to zero and didn't yield any #DIV/0! errors.
Then! I realized that the simplest way to get the actual numbers I wanted, rather than messing with INDEX or AGGREGATE, was to multiply the range Transactions[Out] by the binary array from the IF test. Since the range is a table, I know they will always be the same size. And SUM automatically multiplies element by element and then adds for operations like this.
(The result is a "CSE" formula, which I guess isn't everyone's favorite. I'm still not 100% clear on what it means: just that it outputs data in a single cell, rather than over multiple cells. But in this context, SUM should only output a single number, so I'm not sure why I need CSE... A problem for another day!)
In your IF, the value_if_true clause needs to return an array of the desired row numbers from the array.
MATCH does not return an array of values; it only returns a single value which, with the FALSE parameter, will be the first value. That's why INDEX is only returning the first value.
One way to return an array of values:
Transactions[Category]=I12
will return an array of {TRUE,FALSE,FALSE,TRUE,...} depending on if it matches.
You can then multiply that by the Row number to get the relevant row on the worksheet.
Since you are using a table, to obtain the row number in the data body array, you have to subtract the row number of the Header row.
But now we are going to have an array which includes 0's for the non-matching entries, which is not good for us as a row number argument for the INDEX function.
So we get rid of that by using the AGGREGATE function with the ignore errors argument set after we do change the equality test to 1/(Transactions[Category]=I12) which will create DIV/0 errors for the non-matchers.
Putting it all together
=SUM(INDEX(Transactions[Out],AGGREGATE(15,6,1/(Transactions[Category]=I12)*ROW(Transactions)-ROW(Transactions[#Headers]),ROW(INDIRECT("1:"&COUNTIF(Transactions[Category],$I$12))))))
You may need to enter this with CSE depending on your version of Excel.
Also, if you have a lot of these formulas, you may want to change the k argument for AGGREGATE to use the INDEX function (non-volatile) instead of the volatile INDIRECT function.
=SUM(INDEX(Transactions[Out],AGGREGATE(15,6,1/(Transactions[Category]=I12)*ROW(Transactions)-ROW(Transactions[#Headers]),ROW(INDEX($A:$A,1,1):INDEX($A:$A,COUNTIF(Transactions[Category],$I$12),1)))))
Edit
If you have Excel/O365 with dynamic arrays and the FILTER function, you can greatly simplify the above to the normally entered:
=SUM(FILTER(Transactions[Out],Transactions[Category]=I12))
Problem is straightforward, but solution is escaping. Hopefully some master here can provide insight.
I have a big data grid with prices. Those prices are ordered by location (rows) and business name (cols). I need to match the location/row by looking at two criteria (location name and a second column). Once the matching row is found (there will always be a match), I need to get the minimum/lowest price from two ranges within the grid.
The last point is the real challenge. Unlike a normal INDEX or MINIFS scenario, the columns I need to MIN aren't contiguous... for example, I need to know what the MIN value is between I4:J1331 and Q4:U1331. It's not an intersection, it's a contiguous set of values across two different arrays.
You're probably saying "hey, why don't you just reorder your table to make them contiguous"... not an option. I have a lot of data, and this spreadsheet is used for a bunch of other stuff. So, I have to work with the format I have, and that means figuring out how to do a lookup/min across multiple non-contiguous ranges. My latest attempt:
=MINIFS(AND($I$4:$J$1331,$K$4:$P$1331),$B$4:$B$1331,$A2,$E$4:$E$1331,$B2)
Didn't work, but it should make it more clear what I'm trying to do. There has GOT to be an easy way to just tell excel "use these two ranges instead of one".
Thanks,
Rick
Figured it out. For anyone else who's interested, there doesn't seem to be any easy way to just "AND" arrays together for a search (Hello MS, backlog please). So, what I did instead was to just create multiple INDEX/MATCH arrays inside of a MIN function and take the result. Like this:
MIN((INDEX/MATCH ARRAY 1),(INDEX/MATCH ARRAY 2))
They both have identical criteria, the only difference is the set of arrays being indexed in each function. That basically gives me this:
MIN((match array),(match array))
And Min can then pull the lowest value from either.
Not as elegant as I'd like... lots of redundant code, but at least it works.
-rt
I'm using MCONCAT (part of the morefunc Excel add-in package) to pull extract unique matches from a list of data, my code is as follows:
=MCONCAT(UNIQUEVALUES(OFFSET(B$1,MATCH(D2,A$2:A$68761,0),,COUNTIF(A$2:A$68761,D2))),", ")
This all works OK providing that there is more than one result, otherwise it doesn't seem to work. It DOES work without using UNIQUEVALUES but that returns an enormous amount of results for some lines.
=MCONCAT(OFFSET(B$1,MATCH(D8,A$2:A$68761,0),,COUNTIF(A$2:A$68761,D8)),", ")
Does anyone know how to make my first query work for rows with only a single match?
Many Thanks,
Joe
What's happening here is that UNIQUEVALUES function needs to be passed an "array" and in most cases OFFSET does that.....except when the COUNTIF = 1 and the OFFSET is then just a single value (not an array containing one value) and UNIQUEVALUES doesn't like that so returns an error. I don't know a particularly elegant way round that, perhaps just build a VLOOKUP into the formula when there's an error, i.e.
=IFERROR(MCONCAT(UNIQUEVALUES(OFFSET(B$1,MATCH(D2,A$2:A$68761,0),,COUNTIF(A$2:A$68761,D2))),", "),VLOOKUP(D2,A$2:B$68761,2,0))