spatial-join date-attribute from points to polygon - join

I have a polygon map with inside each polygon multiple points. I would like to spatial-join the date-attribute from the point-layer (join-features) with the date closest to today, to the polygon (Target Features).
Join operation: Join one to one.
i.e. join one datum from points (the one closest to today) to one polygon.
In the merge-rule I can only choose from:
First, Last, Minimum, Maximum, Mean, Median en Mode.
None of these fits my need. Do I miss someting obvious?
First and Last seems to take a date from one of the points inside that polygon. But not always the date I need.
Minimum and Maximum seems to take the miminum/maximum date from the whole Points-population. Not only from the points intersecting the particular polygon.
In the properties-field I see clearly that the attribute-type is Date.
I have both Arcgis and Qgis.

In ArcGIS... This probably needs to be done in a couple steps. I would try:
Do a 1-M spatial join.
Calculate a new field (days from today) on all the records from 1
Where you have multiple matches, determine the minimum days (using the summary statistics tool)
Join the result of 3 with the result of 1
Delete records from 4 where the days from today is greater than the minimum days
You might need to grab an arbitrary OID for the minimum days record if you have multiple points that are the same number of days from today.

Related

How to check if dimension value is available on all days in tableau

I have two input dimensions i.e. Day and Product_sold and I want to create a calculated field "Flag" in Tableau. Basically Flag will show "Yes" if the product was sold on all days, else No (see example attached), can you please help? I have tried multiple things but no use
You can create a fixed LoD calculation to count distinct number of days in data. Then used another fixed LoD (or possibly a table calc) to count distinct days for each product. If the product COUNTD = dataset COUNTD than it sold on every day.
What have you tried so far? This looks like a simple attribution calc that could be put together as boolean eg:
Product_sold = 'computer'
Steve

Sum in ARRAYFORMULA based on possible cell values of two rows, then subtract another sum based on two different date values in two different columns

I really couldn't put the title into words very well. I will link a template spreadsheet below.
I've been working on a formula for hours now however I keep hitting dead ends. I'm unable to effectively do what I believe should be feasible. I'd give my attempts however I believe it would be of zero help, instead I'll explain my desired outcome.
I have a page with my employees, the E column isn't populated right now as I'd like to create a formula (ARRAYFORMULA so I don't have to paste a formula into each cell) to calculate the output based on a few conditions and values.
Vacation days are calculated as follows. The CEO gets 5, managers get 3 and assistants get 1. Extra vacation days based on points employees receive, 30 points or above is 5, 20 points or above is 3 and 10 or above point is 1.
Calculating the amount of vacation days employees have earned wasn't the hard part for me, it was having the formula subtract days based on how many vacation days have been used in the past 30 days.
We log vacations on the vacation page. The formula on the employees page needs to calculate how many vacation days each employee has used in the past 30 days only and subtract that from the total earned vacation days that employee has earned.
I'd like for the formula to use TODAY() to calculate 30 days in the past however for the sake of this example I'll use the date 06/09/2021 instead for continuity.
Sorry if I haven't explained this well or I'm asking too much in one go, I figured all the context is required.
Example sheet

VLOOKUP with wildcard and find Nth occurance?

I'm setting up a Google Sheet that will calculate the most effective purchase size of specific agricultural inputs (fertilizer, chemical, etc). I set up the price data in its own tab with a separate row for each input name + size.
To keep it easy for the user I'd like to require only the input name, # of gallons per acre, and acres and then have a formula spit out the total cost and most effective purchase (bulk if > X gallons, X # of 250 gallon containers + X 55 drums, etc). How can I use the input name plus a wildcard to find the appropriate purchase size?
https://docs.google.com/spreadsheets/d/1bMOPuk2qhmVuJT7vE_ni3KFxfcgKvwTwkM4p50xQF_0/edit?usp=sharing
I tried:
=ArrayFormula(iferror(INDEX('Data (Current)'!H2:H,SMALL(IF($A2&"*"='Data (Current)'!A2:A,ROW('Data (Current)'!A2:A)-1),1))))
...but it returns blank so I'm guessing the reference $A2&"*" to the input name isn't working properly. When I replace it with a string found in the 'Data (Current)' tab then it works fine.
=ArrayFormula(iferror(INDEX('Data (Current)'!H2:H,SMALL(IF($A2&"*"='Data (Current)'!A2:A,ROW('Data (Current)'!A2:A)-1),1))))
I expected the output to be the smallest value (in this case I think it's 5). Then when I change the last number to 2 or 3 it will find the next smallest value, in this case, 55 or 250. Then I can use simple formulas to interact with that and finish the spreadsheet.
Unfortunately, the actual output is nothing, or "".
Sorry if this isn't what you're looking for, as I had some trouble understanding your question.
Presuming what you want is essentially this:
I want to buy Y quantity of item.
I can buy item at cheaper prices if I buy in higher quantities, although sometimes they have a minimum order quantity.
What is the most optimal combination of the options I have to minimize the price I pay?
I'm unsure if there's a simple solution for this within Google Sheets alone. This might be treading more into Apps Script territory.
However, that's not to say that it's not impossible. I've "brute-forced" the above solution above with an iterative-like approach, for the "Chelated Calcium" product: https://docs.google.com/spreadsheets/d/1YSBiSx0IMr4T0R11Dqb-tqOhH4AOTTAWeH2yQfT4X5w
First, list the data in a standardized manner. This includes giving each same product something easy to look it up by. For example, on the Data (Current) tab, I've added 3 columns:
Product Common Name - This is used so that all items of different quantities can be found easily, without needing wildcards.
Gallons - Much easier to parse the data if it it's explicitly laid out.
Minimum Order Gallons - This is your threshold for Bulk. I've set it at an arbitrary 20,000 gallons for Chelated Calcium.
The data here is ordered least-effective first. How you do this will be up to you. In this case, I sorted by the Retail Cost Per Ounce parameter from your sheet, highest first. This eliminates any guesswork about which of the options are most effective, since you can just traverse your options in order. Note: The way I've laid out the formulas will only work IFF the same products are directly next to each other. It won't work if there are other products between them.
On the Field Level Tool tab, standardize your inputs to the Gallons unit. I do this in Total Gallons Needed column (I multiply anything with a "GAL" with 1, and "QUART" with 0.25).
For each item, determine the row numbers where the product begins and ends. This is marked by columns L (Least Efficient Index) and M (Most Efficient Index). I got these results by using the MATCH function.
Set up the iterations, from 0 to N-1. On this sheet, I've set up N=5 iterations, which means that it can traverse 5 different options of the same product only. Since Chelated Calcium only has 4 different options (5 Gal, 30 Gal, 250 Gal, Bulk), 5 is more than enough for this product. If you have products with more options, you may want to have more iterations.
The iterations are on the right side of the Field Level Tool tab.
In your case, you might want to put it on a different tab since the place I put it makes the file look very messy.
In each iteration, I perform the following steps:
To Fulfill - How many gallons still need to be purchased by this iteration?
ThisIndex - What is the row number of this iteration? This is determined by Most Efficient Index - Iteration Number. Remember that since we sorted in order of ascending efficiency, this means that the iteration starts with the most efficient option it can find first. There is a check to make sure that it only outputs a value if it is between the range [Least Efficient Index, Most Efficient Index]. Otherwise, it will be blank to avoid miscalculations by intruding into another product in the Data (Current) tab.
Retail Price, Minimum Gals, Gallons per Order - Simple data extraction for easy usage in the iteration, using INDEX (and indirectly, MATCH by virtue of ThisIndex).
Order - This formula does a couple of things, outlined below:
It checks whether there still remains a valid choice of product at this iteration. It does this by checking whether ThisIndex still exists. If the product doesn't exist, then it will be nulled. This is accomplished by using the IF function.
It will determine if there is a minimum threshold that must be met to purchase this choice. You can see in the 0th iteration, for example, that there is a minimum quantity of 20,000 gallons. If To Fulfill quantity is greater than or equal to the threshold OR there is no threshold, then a purchase is quantified by this column. The mathematics are simply to divide the To Fulfill amount by the Gallons per Order amount to determine the number of orders of this particular product choice. If there is a threshold but the To Fulfill amount doesn't meet it, then this iteration is skipped with a 0 order value.
If the item is already on its least efficient choice (ThisIndex == Least Efficient Index), it will do a CEILING function to ensure that the order is fulfilled. If not, it will do a FLOOR function instead. This is because you cannot order 3.5 units of an item, so they have to be rounded either up or down.
Expenditure - This is simply Order multiplied by the Retail Price, or how much money you spend in this iteration.
Remaining - How much of the product is left unfulfilled at the end of this iteration, to be used as To Fulfill for the next iteration.
Note: If you see formulas that are of the form =IF(ThisIndex, [calculations_here],), that is simply a check to nullify that calculation if ThisIndex is invalid.
Copy the iterations as many times as you want to the right. Something nice to do is to force the iterations to do a CEILING on the very last one to ensure that you never under-buy.
Generate a user-readable string for the purchase suggestion. You can see this on the Suggested Purchase column.
Calculate the Gallons Bought with a simple SUMPRODUCT over all the iterations.
Calculate the total expenditure with a simple SUM over all the iterations.
I hope this is what you were looking for. Regardless, it's at least a fun exercise on how much you can abuse Sheets. ;)

InfluxDB and Grafana graph using midnight as 0 on Y-axis derivative

I am graphing with Grafana (2.6.0) and I have an InfluxDB (0.10.2) database with the following data in it:
> select * from "WattmeterMainskwh" where time > now() - 5m
name: WattmeterMainskwh
-----------------------
time value
1457579891000000000 15529.322
1457579956000000000 15529.411
1457580011000000000 15529.425
1457580072000000000 15529.460
1457580135000000000 15529.476
...etc...
This data collects my household kilowatt usage as measured by a kWH gauge that steadily increments the usage value across months or years. I cannot easily reset the counter, nor do I wish to do so.
My goal is to create a graph that shows my daily kWH use over 24 hour periods starting at midnight, or at a minimum showing relative kWH over the interval displayed. This type of graph would be useful in many other circumstances as well where I could imagine "errors across the day" or "visitors since opening time" or "BGP resets per calendar week" were useful but the collection counter was not reset to zero upon the reset or turn-over of the time interval. This kind of counting is actually quite common in my experience.
This graph works, but doesn't show me what I'm looking for:
SELECT derivative(mean("value")) FROM "WattmeterMainskwh" WHERE $timeFilter GROUP BY time($interval) fill(null)
That graph just shows the difference between one sample and the previous sample. What I want is a steadily increasing line starting from the left side of the graph and increasing towards the right side of the graph, with zero as the bottom of the Y axis, and the graph starting at zero at the farthest left X value.
This graph works too and shows me the correct curve, but it's off by fifteen thousand or so. So far, it's the closest to what I want but since this is an ever-increasing counter that can't be reset I need to subtract some from the Y axis. Ideally, I'd like to subtract whatever the value was at the previous midnight from each sample to get a relative number based on a day instead of an absolute based on all time.
SELECT sum("value") FROM "WattmeterMainskwh" WHERE $timeFilter GROUP BY time($interval) fill(null)
And here's the graph from that previous statement:
Graph that is off by 15k
This attempt didn't work - I apparently can't take a sum of a derivative group:
SELECT sum(derivative(mean("value"))) FROM "WattmeterMainskwh" WHERE $timeFilter GROUP BY time($interval) fill(null)
This doesn't work, either - I can't perform functions within "derivative":
SELECT derivative(sum("value")-first("value")) FROM "WattmeterMainskwh" WHERE $timeFilter GROUP BY time($interval) fill(null)
Of course, I could just create a new value that had calculations applied to it before I wrote it into InfluxDB, but that seems to me to be a data-redundant and sloppy way to solve this problem, as well as being quite inflexible if I want to look at other intervals on a whim. I'm hoping that there is some way to do this more elegantly within the combination of InfluxDB & Grafana, but I'm just not able to find it with the search terms I've used or the thinking I've put towards interpreting the documentation.
Is this type of graph even possible with InfluxDB/Grafana? As far as I can tell a continuous query is not a solution, and the lack of nested SELECTs makes even the hackish ways of doing this not obvious to me.
BONUS: It would be really great to have the graph show midnight every night as a "zero" location, instead of "zero" being the first point in the displayed interval, so looking at five days of normal data would show five distinct "waves" of increasing daily aggregate energy usage, with the wave Y value going back down to zero at 12:00:01 on each day. But I'll take whatever I can get.
Nested functions have only partial support. However, you can effectively nest functions by chaining Continuous Queries.
Use a CQ to calculate the derivative(mean(value)) and store that in a new measurement foo. Then for your graph you can query select sum(value) from foo.
(I know this answer is quite late, but it might help others. Oh, and please excuse me for all the Dutch in my graphs; I had to keep it in dutch for the highest possible WAF)
You could do what I do for my kWh calculations:
Which results in a simple query like this:
SELECT distinct("kwh_combined") FROM "smartmeter" WHERE $timeFilter GROUP BY time($__interval) fill(linear)
In order to get your total count.. or if you want it in a nice graph like this which shows the number of kWh's used per hour in the bars and the yellow line (I normally run in dark mode, excuse the yellow) which is my current WATT power draw:
This data (or at least your hourly usage in bars) can be retrieved by a query like this:
Which is this exact query (for B):
SELECT spread("kwh_combined") FROM "smartmeter" WHERE $timeFilter GROUP BY time(1h) fill(null)
... where the 'kwh_combined' is (still) my counter just counting up and up.
All this results in me being able to 'query' the InfluxDB for a certain time period, like "last 24 hours" to come up with a nice panel like this: (ignore the encircled prices, that was for a question I posted I just made 10 minutes ago, check my PS)
I hope this helps you or anyone else; it took me some figuring out, but I'm happy to give something back to the community :)
PS: Don't be as stupid as I was and hardcode your electrical and gas prices into your dashboard but store them with your measurements as they could change over time.
I had the same problem (same application even) and solved it here. In your case, the query should be roughly:
SELECT value-value_fill FROM
(SELECT first(value) as value_fill FROM WattmeterMainskwh WHERE time>now()-7d GROUP BY time(1d)),
(SELECT first(value) as value FROM WattmeterMainskwh WHERE time>now()-7d GROUP BY time(1h))
fill(previous)

Time and date dimension in data warehouse

I'm building a data warehouse. Each fact has it's timestamp. I need to create reports by day, month, quarter but by hours too. Looking at the examples I see that dates tend to be saved in dimension tables.
(source: etl-tools.info)
But I think, that it makes no sense for time. The dimension table would grow and grow. On the other hand JOIN with date dimension table is more efficient than using date/time functions in SQL.
What are your opinions/solutions ?
(I'm using Infobright)
Kimball recommends having separate time- and date dimensions:
design-tip-51-latest-thinking-on-time-dimension-tables
In previous Toolkit books, we have
recommended building such a dimension
with the minutes or seconds component
of time as an offset from midnight of
each day, but we have come to realize
that the resulting end user
applications became too difficult,
especially when trying to compute time
spans. Also, unlike the calendar day
dimension, there are very few
descriptive attributes for the
specific minute or second within a
day. If the enterprise has well
defined attributes for time slices
within a day, such as shift names, or
advertising time slots, an additional
time-of-day dimension can be added to
the design where this dimension is
defined as the number of minutes (or
even seconds) past midnight. Thus this
time-ofday dimension would either have
1440 records if the grain were minutes
or 86,400 records if the grain were
seconds.
My guess is that it depends on your reporting requirement.
If you need need something like
WHERE "Hour" = 10
meaning every day between 10:00:00 and 10:59:59, then I would use the time dimension, because it is faster than
WHERE date_part('hour', TimeStamp) = 10
because the date_part() function will be evaluated for every row.
You should still keep the TimeStamp in the fact table in order to aggregate over boundaries of days, like in:
WHERE TimeStamp between '2010-03-22 23:30' and '2010-03-23 11:15'
which gets awkward when using dimension fields.
Usually, time dimension has a minute resolution, so 1440 rows.
Time should be a dimension on data warehouses, since you will frequently want to aggregate about it. You could use the snowflake-Schema to reduce the overhead. In general, as I pointed out in my comment, hours seem like an unusually high resolution. If you insist on them, making the hour of the day a separate dimension might help, but I cannot tell you if this is good design.
I would recommend having seperate dimension for date and time. Date Dimension would have 1 record for each date as part of identified valid range of dates. For example: 01/01/1980 to 12/31/2025.
And a seperate dimension for time having 86400 records with each second having a record identified by the time key.
In the fact records, where u need date and time both, add both keys having references to these conformed dimensions.

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