I have this table in access called invoices.
It has a field that performs calculations based on two fields. that is field_price*field_Quantity. Now I added two new columns containing the unit of measure for field_weight and field_quantity named field_priceUnit and field_quantityUnit.
Now instead of just taking the multiplication to perform the calculation, I want it to see if the units of measures match, it doesn't match then it should do a convertion of the field_quantity into the unit of measure of field_priceUnit.
example:
Row1:
ID:1|Field_Quantity:23|field_quantityUnit:LB|Field_weight:256|field_priceunit:KG|field_price:24| Calculated_Column:
the calculated_column should do the calculation this way.
1. if field_quantityunit=LB and field_priceunit=LB then field_quantity*field_price
else
if field_quantityUnit=LB and field_priceUnit=KG
THEN ((field_quantity/0.453592)*field_price) <<
Please help me.
I have to do this for multiple conditions.
Field_priceunit may have values as LB,KG, and MT
Field_quantityUnit may have field as LB,KG, and MT
if both units don't match, then I want to do the conversion and calculate based on the new convetion as seen in the example.
Thank you
The following formula should get you running if your units are only lb and kg and you only have to check one direction:
iif(and(field_quantityunit='LB', field_priceunit='LB'), field_quantity*field_price, (field_quantity/0.453592)*field_price)
This doesn't scale well though as you may have to convert field_price or you may add other units. This iif formula will grow WAY out of hand quickly.
Instead create a new table called unit_conversion or whatever you like:
unit | conversion
lb | .453592
kg | 1
g | 1000
mg | 1000000
Now in your query join:
LEFT OUTER JOIN unit_conversion as qty_conversion
ON field_quantityunit = qty_conversion.unit
LEFT OUTER JOIN unit_conversion as price_conversion
On field_priceUnit = price_conversion.unit
Up in your SELECT portion of the query you can now just do:
(field_quantity * qty_conversion.conversion) * (field_price * price_conversion.conversion)
And you don't have to worry what the units are. They will all convert over to a kilogram and get multiplied.
You could convert everything over to a pound or really any unit of weight here if you want but the nice thing is, you only need to add new units to your conversion table to handle them in any sql that you write this way so it's very scalable.
Related
Given an NxM array of positive integers, how would one go about selecting integers so that the maximum sum of values is achieved where there is a maximum of x selections in each row and y selections in each column. This is an abstraction of a problem I am trying to face in making NCAA swimming lineups. Each swimmer has a time in every event that can be converted to an integer using the USA Swimming Power Points Calculator the higher the better. Once you convert those times, I want to assign no more than 3 swimmers per event, and no more than 3 races per swimmer such that the total sum of power scores is maximized. I think this is similar to the Weapon-targeting assignment problem but that problem allows a weapon type to attack the same target more than once (in my case allowing a single swimmer to race the same event twice) and that does not work for my use case. Does anybody know what this variation on the wta problem is called, and if so do you know of any solutions or resources I could look to?
Here is a mathematical model:
Data
Let a[i,j] be the data matrix
and
x: max number of selected cells in each row
y: max number of selected cells in each column
(Note: this is a bit unusual: we normally reserve the names x and y for variables. These conventions can help with readability).
Variables
δ[i,j] ∈ {0,1} are binary variables indicating if cell (i,j) is selected.
Optimization Model
max sum((i,j), a[i,j]*δ[i,j])
sum(j,δ[i,j]) ≤ x ∀i
sum(i,δ[i,j]) ≤ y ∀j
δ[i,j] ∈ {0,1}
This can be fed into any MIP solver.
I want to create a dynamic array that returns me X values based on given probabilities. For instance:
Imagine this is a gift box and you can open the box N times. What I want is to have N random results. For example, I want to get randomly 5 of these two rarities but based on their chances.
I have this following formula for now:
=index(A2:A3,randarray(5,1,1,rows(A2:A3),1). And this is the output I get:
The problem here is that I have a dynamic array with the 5 results BUT NOT BASED ON THE PROBABILITIES.
How can I add probabilities to the array?
Here is how you could generate a random outcome with defined probabilities for the entries (Google Sheets solution, not sure about Excel):
=ARRAYFORMULA(
VLOOKUP(
RANDARRAY(H1, 1),
{
{0; OFFSET(C2:C,,, COUNTA(C2:C) - 1)},
OFFSET(A2:A,,, COUNTA(C2:C))
},
2
)
)
This whole subject of random selection was treated very thoroughly in Donald Knuth's series of books, The Art of Computer Programming, vol 2, "Semi-Numerical Algorithms". In that book he presents an algorithm for selecting exactly X out of N items in a list using pseudo-random numbers. What you may not have considered is that after you have chosen your first item the probability array has changed to (X-1)/(N-1) if your first outcome was "Normal" or X/(N-1) if your first outcome was "Rare". This means you'll want to keep track of some running totals based on your prior outcomes to ensure your probabilities are dynamically updated with each pick. You can do this with formulas, but I'm not certain how the back-reference will perform inside an array formula. Microsoft's dynamic array documentation indicates that such internal array references are considered "circular" and are prohibited.
In any case, trying to extend this to 3+ outcomes is very problematic. In order to implement that algorithm with 3 choices (X + Y + Z = N picks) you would need to break this up into one random number for an X or not X choice and then a second random number for a Y or not Y choice. This becomes a recursive algorithm, beyond Excel's ability to cope in formulas.
I need to obtain Cuml % in Spotfire; how to do? Please refer the below data-set
Data Set
You'll want to use the OVER function. I re-created your data table, then inserted three calculated columns:
ActualCuml = Sum([Actual]) OVER (AllPrevious([Day]))
PlannedCuml = Sum([Planned]) OVER (AllPrevious([Day]))
CumlPct = [ActualCuml] / [PlannedCuml]
The first two calculated columns are your rolling sums for Actual and Planned, and then the third column just divides those two new columns to get the cumulative percentage.
You could just insert a single calculated column and use the expressions from the first two as the division factors:
Sum([Actual]) OVER (AllPrevious([Day])) / Sum([Planned]) OVER (AllPrevious([Day]))
Say I have two tables. attrsTable:
file | attribute | value
------------------------
A | xdim | 5
A | ydim | 6
B | xdim | 7
B | ydim | 3
B | zdim | 2
C | xdim | 1
C | ydim | 7
sizeTable:
file | size
-----------
A | 17
B | 23
C | 34
I have these tables related via the 'file' field. I want a PowerPivot measure within attrsTable, whose calculation uses size. For example, let's say I want xdim+ydim/size for each of A, B, C. The calculations would be:
A: (5+6)/17
B: (7+3)/23
C: (1+7)/34
I want the measure to be generic enough so I can use slicers later on to slice by file or attribute. How do I accomplish this?
I tried:
dimPerSize := CALCULATE([value]/SUM(sizeTable[size])) # Calculates 0
dimPerSize := CALCULATE([value]/SUM(RELATED(sizeTable[size]))) # Produces an error
Any idea what I'm doing wrong? I'm probably missing some fundamental concepts here of how to use DAX with relationships.
Hi Redstreet,
taking a step back from your solution and the one proposed by Jacob, I think it might be useful to create another table that would aggregate all the calculations (especially given you probably have more than 2 tables with file-specific attributes).
So I have created one more table that contains (only) unique file names, and thus the relationships could be visualized this way:
It's much simpler to add necessary measures (no need for calculated columns). I have actually tested 2 scenarios:
1) create simple SUM measures for both Attribute Value and File Size. Then divide those two measures and job done :-).
2) use SUMX functions to have a bit more universal solution. Then the final formula for DimPerSize calculation could look like this:
=DIVIDE(
SUMX(DISTINCT(fileTable[file]),[Sum of AttrValue]),
SUMX(DISTINCT(fileTable[file]),[Sum of FileSize]),
BLANK()
)
With [Sum of AttrValue] being:
=SUM(attrsTable[value])
And Sum of FileSize being:
=SUM(sizeTable[size])
This worked perfectly fine, even though SUMX in both cases goes over all instances of given file name. So for file B it also calculates with zdim (if there is a need to filter this out, then use simple calculate / filter combination). In case of file size, I am using SUMX as well, even though it's not really needed since the table contains only 1 record for each file name. If there would be 2 instances, then use SUMX or AVERAGEX depending on the desired outcome.
This is the link to my source file in Excel (2010).
Hope this helps.
You look to have the concept of relationships OK but you aren't on the right track in terms of CALCULATE() either in terms of the structure or the fact that you can't simply use 'naked' numerical columns, they need to be packaged in some way.
Your desired approach is correct in that once you get a simple version of the thing running, you will be able to slice and dice it over any of your related dimensions.
Best practice is probably to build this up using several measures:
[xdim] = CALCULATE(SUM('attrstable'[value]), 'attrstable'[attribute] = "xdim")
[ydim] = CALCULATE(SUM('attrstable'[value]), 'attrstable'[attribute] = "ydim")
[dimPerSize] = ([xdim] + [ydim]) / VALUES('sizeTable'[size])
But depending on exactly how your pivot is set up, this is likely to also throw an error because it will try and use the whole 'size' column in your totals. There are two main strategies for dealing with this:
Use an 'iterative' formula such as SUX() or AVERAGEX() to iterate individually over the 'file' field and then adds up or averages for the total e.g.
[ItdimPerSize] = AVERAGEX(VALUES('sizeTable'[file]), [dimPerSize])
Depending on the maths you want to use, you might find that produce a useful average that you need to use SUMX but devide by the number of cases i.e. COUNTROWS('sizeTable'[file]).
You might decide that the totals are irrelevant and simply introduce an error handling element that will make them blank e.g.
[NtdimPerSize] = IF(HASONEVALUE('sizeTable'[file]),[dimPerSize],BLANK())
NB, all of this assumes that when you are creating your pivot that you are 'dragging in' the file field from the 'sizetable'.
I'm making a spreadsheet in excel to help me understand how starting a part-time business on top of my full time job might affect my tax. I need to do this because I'm very close to my next UK tax bracket and I want to know exactly how it might affect my finances.
As part of this I'm trying to write an excel formula that will add two numbers then check if this new number is greater than a third number. I will refer to the two numbers added together as A and the third number as B. If A is not greater than B then I will multiply by 20% to find out how much of it is owed in tax. If A is greater than B I will subtract B from A to create number C and multiply B by 20% and C by 40% and add the two together to produce the final number I need. Can someone please xplain to me how to script this in Excel? I've looked for online examples but I'm not finding the language very penetrable. If I was using a scripting language I was more familiar with the code would look like this:
float taxThreshold = 42011.00;
int income = foo;
if(taxThreshold < income)
{
float higherRate = income-taxThreshold;
float standardTaxOwed = taxThreshold * 20%;
float higherRateOwed = higherRate * 40%;
float finalTaxOwed = standardTaxOwed+higherTaxOwed;
}
else
{
float finalTaxOwed = income * 20%;
}
I'm sure this is very simple to do, I just don't get the excel syntax. Can someone show me how this should be done? You'd not only be solving this problem but also giving me a means of translating from my current scripting knowledge into excel.
The easiest way is to store your 4 input parameters in some cells - and then name them. To do so, select the cell and type a meaningful name into the field that shows the address (i.e. left of the formula bar).
Once you have done this, you can simply use this formula:
=IF(Income>Threshold,Threshold*StandardTaxRate+(Income-Threshold)*HighTaxRate,Income*StandardTaxRate)
Without the naming, the formula would be something like this:
=IF(B2>B1,B1*B7+(B2-B1)*B8,B2*B7)
Both formulas will calculate you the tax you'd need to pay. If you want it more explicit, I'd recommend a layout such as this:
The formulas would read:
C7: =IF(B2>B1,B1,B2)
C8: =IF(B2>B1,B2-B1,0)
D7: =B7*C7
D8: =B8*C8
HTH!