I have a table of data with many data repeating.
I have to sort the rows by random, however, without having identical names next to each other, like shown here:
How can I do that in Excel?
Perfect case for a recursive LAMBDA.
In Name Manager, define RandomSort as
=LAMBDA(ζ,
LET(
ξ, SORTBY(ζ, RANDARRAY(ROWS(ζ))),
λ, TAKE(ξ, , 1),
κ, SUMPRODUCT(N(DROP(λ, -1) = DROP(λ, 1))),
IF(κ = 0, ξ, RandomSort(ζ))
)
)
then enter
=RandomSort(A2:B8)
within the worksheet somewhere. Replace A2:B8 - which should be your data excluding the headers - as required.
If no solution is possible then you will receive a #NUM! error. I didn't get round to adding a clause to determine whether a certain combination of names has a solution or not.
This is just an attempt because the question might need clarification or more sample data to understand the actual scenario. The main idea is to generate a random list from the input, then distribute it evenly by names. This ensures no repetition of consecutive names, but this is not the only possible way of sorting (this problem may have multiple valid combinations), but this is a valid one. The solution is volatile (every time Excel recalculates, a new output is generated) because RANDARRAY is volatile function.
In cell D2, you can use the following formula:
=LET(rng, A2:B8, m, ROWS(rng), seq, SEQUENCE(m),
idx, SORTBY(seq, RANDARRAY(m,,1,m, TRUE)), rRng, INDEX(rng, idx,{1,2}),
names, INDEX(rRng,,1), nCnts, MAP(seq, LAMBDA(s, ROWS(FILTER(names,
(names=INDEX(names,s)) * (seq<=s))))), SORTBY(rRng, nCnts))
Here is the output:
Update
Looking at #JosWoolley approach. The generation of the random sorting can be simplified so that the resulting formula could be:
=LET(rng, A2:B8, m, ROWS(rng), seq, SEQUENCE(m), rRng,SORTBY(rng, RANDARRAY(m)),
names, TAKE(rRng,,1), nCnts, MAP(seq, LAMBDA(s, ROWS(FILTER(names,
(names=INDEX(names,s)) * (seq<=s))))), SORTBY(rRng, nCnts))
Explanation
LET function is used for easy reading and composition. The name idx represents a random sequence of the input index positions. The name rRng, represents the input rng, but sorted by random. This sorting doesn't ensure consecutive names are distinct.
In order to ensure consecutive names are not repeated, we enumerate (nCnts) repeated names. We use a MAP for that. This is a similar idea provided by #cybernetic.nomad in the comment section, but adapted for an array version (we cannot use COUNTIF because it requires a range). Finally, we use SORTBY with input argument by_array, the map result (nCnts), to ensure names are evenly distributed so no consecutive names will be the same. Every time Excel recalculate you will get an output with the names distributed evenly in a different way.
Not sure if it's worth posting this, but I might as well share the results of my research such as it is. The problem is similar to that of re-arranging the characters in a string so that no same characters are adjacent The method is just to insert whichever one of the remaining characters (names) has the highest frequency at this point and is not the same as the previous character, then reduce its frequency once it has been used. It's fairly easy to implement this in Excel, even in Excel 2019. So if the initial frequencies are in D2:D8 for convenience using Countif:
=COUNTIF(A$2:A$8,A2)
You can use this formula in (say) F2 and pull it down:
=INDEX(A$2:A$8,MATCH(MAX((D$2:D$8-COUNTIF(F$1:F1,A$2:A$8))*(A$2:A$8<>F1)),(D$2:D$8-COUNTIF(F$1:F1,A$2:A$8))*(A$2:A$8<>F1),0))
and similarly in G2 to get the ages:
=INDEX(B$2:B$8,MATCH(MAX((D$2:D$8-COUNTIF(F$1:F1,A$2:A$8))*(A$2:A$8<>F1)),(D$2:D$8-COUNTIF(F$1:F1,A$2:A$8))*(A$2:A$8<>F1),0))
I'm fairly sure this will always produce a correct result if one is possible.
HOWEVER there is no randomness built in to this method. You can see if I extend it to more data that in the first several rows the most common name simply alternates with the other two names:
Having said that, this is a bit of a worst case scenario (a lot of duplication) and it may not look too bad with real data, so it may be worth considering this approach along with the other two methods.
So, I have a dataframe with 3D point cloud data (X,Y,Z,Color):
dataframe sample
Basically, I need to group the data according to the color column (which takes values of 0,0.5 and 1). However, I don't need an overall grouping (this is easy). I need it to create new dataframes every time the value changes. That is, I'd like a new dataframe for every set of rows that are followed by and preceded by 5 zeros (because single zeros are sometimes erroneously present in chunks of data that I'm interested in).
Basically, the zero values (black) are meaningless for me; I'm only interested in the 0.5 (red) and 1 values (green). What I want to accomplish is to segment the original point cloud into smaller clusters that I can then visualize. I hope this is clear. I can't seem to find answers to my question anywhere.
First of all, you should understand the for loop well. Python is a great programming language for using the code of any library inside functions and loops. Let's say you have a dataset and you want to navigate and control column a. First, let's start the loop with the "for i in dataset:" code. When you move to the bottom line, you have now specified the criteria you want with the code if "i[a] > 0.5:" in each for loop. Now if the value is greater than 0.5, you can write the necessary codes to create a new dataset with all the data of the row you are in. In terms of personal training, I did not write ready-made code.
I am using Surveymonkey for a questionnaire. Most of my data has a regular scale from 0-6, and additionally an "Other" option that people can use in case they choose to not answer the item. However, when I download the data, Surveymonkey automatically assigns a value of 0 to that not-answer category, and it appears this cant be changed.
This leads to me not knowing when a zero in my numeric dataset actually means zero or just participants choosing to not answer the question. I can only figure that out by looking at another file that includes the labels of participants answers (all answers are provided by the corresponding labels, so this datafile misses all non-labeled answers...).
This leads me to my problem: I have two excel files of same size. I would need to find a way to find certain values in one dataset (text value, scattered randomly over dataset), and replace the corresponding numeric values in the other dataset (at the same position in the dataset) with those values.
I thought it would just be possible to find all values and copy paste in the same pattern, but I cannot seem to find a way to do that. I feel like I am missing an obvious solution, but after searching for quite a while I really could not find an answer to my specific question.
I have never worked with macros or more advanced excel programming before, but have a bit of knowledge about programming in itself. I hope I explained this well, I would be very thankful for any suggestions or scripts that could help me out here!
Thank you!
Alex
I don't know how your Excel file is organised, but if it's like the legacy Condensed format, all you should need to do is to select the column corresponding to a given question (if that's what you have), and search and replace all 0 (match entire cell) with the text you want.
I have about 100 columns with some empty values that I would like to replace with zeroes. I know how to do this with a single column using Calculate and Replace, but I wanted to see if there was a way to do this with multiple columns at once.
Thanks!
You could script it but it'd probably take you as long to write the script as it would to do it manually with a transformation. A better idea would be to fix it in the data source itself before you import it so SPOTFIRE doesn't have to do the transformation every time, which if you are dealing with a large amount of data, could hinder your performance.
I have an Excel spreadsheet where each column is a certain variable. At the end of my columns I have a special last column called "Type" which can be A, B, C, or D.
Each row is a data point with different variables that ends up in a certain "Type" bucket (A/B/C/D) recorded in the last column.
I need a way to examine all entries of a certain type (say, "C" or "C"|"D") and find out which of the variable(s) is a good predictor of this last column, and which are better predictors than others.
Some variables are numbers, others are fixed strings (from a set of strings), so it's not just a number/number correlation.
Is Excel 2003 a good tool for that, or are there better statistical programs that make this easier? Do I create a Pivot/Histogram for each category, or is there a better way to run these queries? Thanks
You can make some filtering, especially to clean the data (I mean, to change the data values into one type, string or numeral) using microsoft excel. Execl also makes some data mining. However, for the kind of problems you have, a good tool that I recommend you is WEKA. Using this tool, you can make associative classification prediction (i.e., class association rule mining)of all data instances(rows) and therefore, you can determine which items fall belong to A/B/C/D. Your special attribute will be your class attribute.