I want to setup a system by which employees have a set number of points that they can use to weight against each holiday, basically if they don't want to work on a certain holiday they would set a large number of points on that day. We would then setup holiday assignments such that there are two people on each holiday and each person works 2 holidays; there are 8 employees with 8 "holidays", so the matrix is 8x8.
I setup a preference array that has a preference number for each employee, call it P.
I setup an assignment array for year 1, call it Y1.
I then take SUM(P*Y1) to get the total points for Year 1.
I solve to minimize SUM(P*Y1), subject to the constraints above: 2 holidays/employee, 2 employees/holiday. Assignments are integers <=1.
The solver gives a solution that looks reasonable.
I then repeat the formula above, but I use a new assignment array for year 2, Y2.
I then setup a matrix of Y1+Y2, giving the total points over two years.
I also setup a matrix of Y1*Y2=0, ie no repeat assignments.
I use Solver to minimize SUM(PY1+PY2) by changing the year 2 assignments, Y2. Again, with the constraints of 2 employees per holiday, 2 holidays per employee.
I expect it to give me the second lowest point total possible. It does not, it gives me the same solution as in Y1, and Y1Y2<>0.
Is this my math, or is it the Solver? It gives the absolute minimum without following the constraint of not repeating any values, ie Y1Y2=0.
Related
So, the point is, in my dataset I have to create a variable "Moving Avg. Amt paid per sq. ft." and the formula or the logic I need is to calculate the last five values as per most recent transactions. i.e. most recent sales by date. but this average should only return value in case it matches the same building and same area variable.
This is what my data looks like
Area ID has three categories. Building number has 5 categories. Date is sorted in ascending order. Now my variable moving average should calculate last 5 averages w.r.t date but for the same building in the same area. e.g. there are buildings 1 and 2 in area 102. I need my Mov Avg. variable to calculate using conditions when it matches criteria of building 1 in 102 for past five sales and when it finds building 2 in the building number variable, it should calculate average of last 5 sales of that building in area 102.
So my approach to this issue was (which is flawed at the moment):
I calculate average of amount paid per sq. foot w.r.t area & building based on dates using the formula
=AVERAGEIFS($N$2:$N$6547,$D$2:$D$6547,D14,$C$2:$C$6547,C14,$B$2:$B$6547,B14)
but I cannot make this formula work, to calculate moving average whenever it meets the criteria. I tried the offset the point as well by 5 but the logic is not right and hence its not working and returning #value in the cells. The formula I used to offset the above condition is
=AVERAGEIFS((OFFSET(N13,5,,5)),$D$2:$D$6547,D13,$C$2:$C$6547,C13,$B$2:$B$6547,B13)
(These formulae are used in column Q of my data)
Need a support from the community as I am badly stuck in making this data useful and I am out of any ideas to make this work.
Edit 1: I am not sure how I can attach my excel file here so you may review the dataset. I have uploaded it on a third party site, for which the link is shared below, so you can view the file in detail.
https://file.io/hlciAHJOHzWA
Expected result is as I have mentioned the instruction said
"Create a variable called "mov. avg amt. paid per sq ft". For each row, this variable should calculate average amt paid per sq ft for the most recent past five sales (by date) for the same building in the same area."
And my approach to build a logic or formula to make this variable calculate moving average w.r.t date for same building in the same area doesn't seem to work because there might be some flaws.
In Office 365 you could use:
=LET(f,FILTER($N$1:N13,($B$1:B13=B14)*($C$1:C13=C14),""),
c,COUNTA(f),
s,SEQUENCE(5,,c-5),
IFERROR(IF(c<5,SUM(f)/c,SUM(INDEX(f,s))/5),""))
If there's less than 5 matches prior to the current sales it'll calculate the average of the count. If 5 or more matches it'll calculate the average of the last 5 prior to the current sale.
I have a set of dates, in total 7 periods spanning 6 months each with corresponding calculation factor.
I will have user input of period for which they'd want the calculation to be done, which can fall within one of the 6 months periods or encompass between two or more such periods wholly or partially.
Illustration:
The preset periods:
User input:
I've obtained decimal value (monthly basis) of the periods input by the user for calculation. For first instance (see user input), the decimal value for the period 01-01-2015 to 29-04-2015 will be 3.97 on monthly basis. The calculation for that period would be like:
n*3.97*113%
For the second instance, the decimal value for the period 30-04-2015 to 30-06-2015 would be 2.03, which would be used to do calculation at 113% and then the result will be added to the calculation done at 119% using the decimal value 5.65 for the period 01-07-2015 to 20-12-2015:
(n*2.03*113%)+(n*5.65*119)
Think I can handle the breaking up of periods since the revision event is bi-annual on particular dates but advice regards to that is welcome. More importantly, I need help tracing the preset calculation factor (say 132%) corresponding to the period input by the user as illustrated above. Is it feasible?
I will use the standard approach for finding the overlap between two dates and will split the task into three parts as in my answer to this recent question.
(1) The first part is finding the overlap between the user's range of dates and one or more revision periods in whole months and will need an array formula. I have chosen to use the Datedif function 1 to get the difference in months between the beginning and end of the overlaps. If there is no overlap, the start date fed in to Datedif will be after the end date, and it will return an error which can be trapped by Iferror. If the user's dates start in A2 and B2, this gives in C2:
=SUM(IFERROR((DATEDIF(IF(K$2:K$8>A2,K$2:K$8,A2),IF(L$2:L$8<B2,L$2:L$8,B2),"m")+1)*M$2:M$8,0))
which has to be entered as an array formula using CtrlShiftEnter
The above result includes the first and last months entered by the user even if they are incomplete months. It's then necessary to subtract any missing days in the first and last months.
(2) Missing days in first month as a fraction of the number of days in that month in D2:
=SUMIFS($M$2:$M$8,$K$2:$K$8,"<="&A2,$L$2:$L$8,">="&A2)*(A2-EOMONTH(A2,-1)-1)/(EOMONTH(A2,0)-EOMONTH(A2,-1))
A noted by OP, this could also have been done using sumproduct, vlookup or index/match.
(3) Missing days in last month as a fraction of days in that month in E2:
=SUMIFS($M$2:$M$8,$K$2:$K$8,"<="&B2,$L$2:$L$8,">="&B2)*(EOMONTH(B2,0)-B2)/(EOMONTH(B2,0)-EOMONTH(B2,-1))
The total is just (1)-(2)-(3) or
=C2-D2-E2
I have put the results of OP's two examples for comparison in H2 and H3: my results agree with them in the first 3 significant figures.
n*3.97*113%
(n*2.03*113%)+(n*5.65*119)
In all cases I have set n=1 and ignored the fact that the rate is a percentage.
This shows how the results would be calculated manually:
1 Pros of using Datedif:
(1) Works across year boundaries unlike just using Month function.
(2) Works conveniently with Iferror to identify non-matching date ranges.
Cons of using Datedif:
(1) It is an undocumented function and may be withdrawn in future.
(2) In this particular case, all date calculations are within the same year so Month would be useable.
Say I have the following data:
Year Day Amount
2015 1 2
2015 2 3
2015 3 4
2015 4 5
Using window functions or aggregations, I want to get a number for each row that represents the "linearity based on the previous n rows". In this simple example, for the row with day = 4, linearity would be pretty high, for obvious reasons, based on the previous n days, where n is 3.
Issues pop up when some of the previous days do not exist, and in that case, I would just want to use a default value of -1, for example to indicate otherwise.
I don't have an exact value I want to represent the linearity, but as an example, similar to correlation coefficients, 1 could represent high linearity, while 0 none.
Edit:
What I have done as a makeshift use-case was add a column to each row representing the day (and taking year into account), and used a window function, with lag to find the previous 4 values (if they existed). After getting (or not getting these values), I made a simple calculation to calculate the difference of each combination of points, and used division to see how close they were to each other (1 would be the best). I apologize, I cannot share any code due to an agreement of code sharing.
generate series with all dates you want to estimate
left outer join it with input
replace null values for Amount with a valuet to estimate
convert to RDD
generate keys with lower bound -> for 2015 4 generate keys [2015 4, 2015 3, 2015 2] amd flatten
groupByKey
estimate for groups
I'd like to use Excel to generate a randomized lab partner list, without using VB (due to security settings on the PCs).
Parameters are as follows:
Number of students: 10-30, one worksheet per total number desired
Number of partners: Three for first two labs, and two for the other four-five.
Number of lab stations: 10
Repeats: Ideally none, but it is permissible for a student to have a repeat partner from one of the first two labs.
Excel version: 2007
To clarify, each student will have two labs where they share a lab station with up to two other students, giving a maximum lab size of 30 students. After that, they will be strictly limited to two students per station, giving a maximum of 20 students. Each student will have four of these limited labs, with there being a total of five such labs presented, to allow for either odd-numbered classes, or a class size between 21-30.
Each student is simply numbered from 1-30, so a cell could, for instance, state "5, 24" as the two students for that lab station.
True RNG is not important, and in fact, only needs to be performed once to make these matrices.
I think this is a bit tricky without using VBA, but here is one approach that is OK for small groups. I have tried it using a group of just nine so that the screen shot should be readable.
The method is basic Fisher-Yates
A Start with a group of students size n represented by a list of numbers 1 to n.
B Generate a random number r in range 1 to n
C Pick the rth element from the list
D Remove the rth element from the list
E Reduce n by 1
F Repeat from B until n=1.
In Excel:-
Fill A2:A10 and D2:L2 with numbers 1-9
Put the following in B2 and pull down:-
=RANDBETWEEN(1,10-A2)
Put this in C2 and pull down:-
=OFFSET(D2,0,B2-1)
Put this in D3 and pull down and across:-
=IF(D2>=$C2,E2,D2)
The ID's will be in column C so the first three would be in group 1, the next three in group 2 etc.
By the way, your question is a special case of generating non-repeating random numbers - see
Generating unique random numbers without VBA
The array formula described here does it in one step - modified slightly for this problem it would look like
=SMALL(IF(COUNTIF(C$1:C1,ROW(INDIRECT("1:9")))=0,ROW(INDIRECT("1:9"))),RANDBETWEEN(1,(9-ROWS(C$2:C2)+1)))
I'm trying to use excel to calculate the average frequency of delivery for a set of parts. I have a data set that has two columns- part number and delivery date. I'm trying to figrue out out oftne parts get delivered, on average, in terms of days. I tried using nested ifs like averageif(a2=a2:b9999,datedif(xx)) etc, but to no avail. I'm looking for this:
Input:
Part A 8.1
Part A 8.8
Part A 8.15
Output: Part A Average Delivery - Every 7 Days
etc etc. Any ideas?
If your dates are in ColumnB:
=(MAX(B:B)-MIN(B:B)--1)/COUNT(B:B)
or:
=(MAX(B:B)+1-MIN(B:B))/COUNTA(B:B)
should serve.
Edit
If you have multiple parts (the above assumed only one) and the list is in no particular order then a PivotTable may be best (say with its top left-hand corner in D1), in Tabular form with Part for Row Labels and Delivery three times for Σ Values (the first as MAX, the second as MIN and the third as COUNT). Then =(1+E3-F3)/G3 copied down should give you the average bumber of days between deliveries. For example 5 in your example (3 deliveries in 15 days).