I have a rails conditional statement that states, among other conditions:
where(['[...],hour_id >= ? AND hour_id <= ?', [...] session[:hour], #end_period)
the hours are indexed via their 24-hour clock number.
This condition is incomplete as the need is to extract the record which is true for the lowest valid hour of that span. i.e. we are at hour 13 and we have objects at hours 17, 18 and 19. At present it can extract any of 17, 18 and 19; this needs to be restricted to '17'.
Order the items by the hour and pick the first:
where(:hour_id => (session[:hour]..#end_period)).order(:hour_id).first
Btw you can use this range syntax to query for a value that should between to other values.
Related
In my cube, I have several measures at the day grain that I'd like to sum at the day grain but average (or take latest) at the month grain or year grain.
Example:
We have a Fact table with Date and number of active subscribers in that day (aka PMC). This is snapshotted per day.
dt
SubscriberCnt
1/1/22
50
1/2/22
55
This works great at the day level. At the month level, we don't want to sum these two values (count = 105) because it doesn't make sense and not accurate.
when someone is looking at month grain, it should look like this - take the latest for the month. (we may change this to do an average instead, management is still deciding)
option 1 - Take latest
Month-Dt
Subscribers
Jan-2022
55
Feb-2022
-
option 2 - Take aveage
Month-Dt
Subscribers
Jan-2022
52
Feb-2022
-
I've not been able to find the right search terms for this but this seems like a common problem.
I added some sample data at the end of a month for testing:
dt
SubscriberCnt
12/30/21
46
12/31/21
48
This formula uses LASTNONBLANKVALUE, which sorts by the first column and provides the latest value that is not blank:
Monthly Subscriber Count = LASTNONBLANKVALUE( 'Table'[dt], SUM('Table'[SubscriberCnt]) )
If you do an AVERAGE, a simple AVERAGE formula will work. If you want an average just for the current month, then try this:
Current Subscriber Count =
VAR _EOM = CLOSINGBALANCEMONTH( SUM('Table'[SubscriberCnt]), DateDim[Date] )
RETURN IF(_EOM <> 0, _EOM, AVERAGE('Table'[SubscriberCnt]) )
But the total row will be misleading, so I would add this so the total row is the latest number:
Current Subscriber Count =
VAR _EOM = CLOSINGBALANCEMONTH( SUM('Table'[SubscriberCnt]), DateDim[Date] ) //Get the number on the last day of the month
VAR _TOT = NOT HASONEVALUE(DateDim[MonthNo]) // Check if this is a total row (more than one month value)
RETURN IF(_TOT, [Monthly Subscriber Count], // For total rows, use the latest nonblank value
IF(_EOM <> 0, _EOM, AVERAGE('Table'[SubscriberCnt]) ) // For month rows, use final day if available, else use the average
)
I have a list of products and would like to get a 50 day simple moving average of its volume using Power Query (M).
The table is sorted by product name and date. I add a custom column and applied the code below.
if [date] >= #date(2018,1,29)
then List.Average(List.Range(Source[Volume],[Volume]-1,-50))
else ""
Since it is already sorted by date and name, an if statement was applied with a date as criteria/filter. However, an error occurs that says
'Volume' column not found in the table.
I expect to have an added column in the power query with volume 50 day moving average per product. the calculation to be done if date is greater than or equal Jan 29, 2018.
We don't know what your columns are, but assuming you have [product], [date] and [volume] in Source, this would average the last 50 days of [volume] for the identical [product] based on each [date], and place in a new column
AvgAmountAdded = Table.AddColumn(Source, "AverageAmount", (i) => List.Average(Table.SelectRows(Source, each ([product] = i[product] and [date]<=i[date] and [date]>=Date.AddDays(i[date],-50)))[volume]), type number)
Finally! found a solution.
First, apply Index by product see this post for further details
Then index again without criteria (index all rows)
Then, apply below code
= Table.AddColumn(#"Previous Step", "Volume SMA(50)", each if [Index_byProduct] >= 50 then List.Average(List.Range(#"Previous Step"[Volume], ([Index_All]-50),50)) else 0),
For large dataset, Table.Buffer function is recommended after index-expand step to improve PQ calculation speed
I have a bar chart with X axis as discrete date value and Y axis as number of records.
eg: x axis (Filtered Date)- 1st Oct, 2nd Oct, 3rd Oct etc
y axis (Number of Records)- 30, 4, 3 etc
Now, I have to create a table to get Max, Min and Avg. Value of the 'Number of Record'.
I have written a Calculated Field as MAX([Number of Records]) to get the maximum of Number of Records in this case 30 but I always get a value of 1.
How do I define the values to get max, min and avg. ?
Thanks,
Number of Records is an automatically calculated field that tableau generates when importing a datasource. You can right click on it and see the definition of the calculation: 1.
As you currently have your field defined, tableau will look for the maximum value of the column. It will always be 1 because that is the only value in that field for every record.
It sounds like you are actually trying to calculate the maxiuum of the sum of the number of records for your aggregation level (in your case date). You should be able to easily accomplish this using Level of Detail (LOD) expressions, or table calculations. Something like the following:
WINDOW_MAX(SUM([Number of Records]))
I am stumped. I have a Timesheet class that holds work days in a dictionary called self.timesheet with dates as the keys and hours, rate as values. I am trying to write a function that can show all the entries in a user defined range of dates.
for now lets assume the key dates are simple integers 20 - 25. i tried this and it didn't do anything at all. no errors, just nothing.
def show_days(self):
date_from = input("From date: ")
date_to = input("To date: ")
t = self.timesheet
for dates in t[date]:
range(date_from, date to)
print(dates)
I can see this doesn't look right , I feel I need *for dates in range(date_from, date_to)* but I can't figure how to get it to loop over the dictionary keys like that.
You need to loop over the range, then check if that key is in the dictionary:
for day in range(date_from, date_to + 1):
if day in t:
print day, t[day]
Note that the values produced by range() do not include the end point, so I used date_to + 1 to ensure it is included anyway.
If your keys are not integers but, say, datetime.date objects, you'll have to construct some kind of loop with datetime.timedelta() to iterate over all dates between two values:
date = date_from = datetime.date(2012, 1, 15)
date_to = datetime.date(2012, 3, 12)
while date <= date_to:
if date in t:
print date, t[date]
date += datetime.timedelta(days=1)
I'm trying to figure out a DateAdd() equivalent in Oracle that is actually the difference in seconds between 2 columns in the same table:
SELECT
DISTINCT p.packet_id,
p.launch_dt,
r.route_duration,
s.completion_date,
DATEADD(SS, r.route_duration, p.launch_dt) AS tempDate
FROM
tdc_arc_apprpkt_def p
JOIN tdc_arc_inpr_route_def r
ON p.packet_id = r.packet_id
JOIN tdc_arc_inpr_route_step_detai s
ON p.packet_id = s.packet_id
AND s.completion_date > DATEADD(SS, r.route_duration, p.launch_dt)
Any help would be greatly appreciated!
In addition to being able to do date arithmetic using fractions of days as Tony demonstrates, assuming you are using 9i or later, you can also use interval functions (or, even better, define the ROUTE_DURATION column as an interval) and add intervals to dates. In your case, you can do
p.launch_dt + numtodsinterval( r.route_duration, 'SECOND' )
to add route_duration seconds to launch_dt.
If you were to define the route_duration column as an INTERVAL DAY TO SECOND rather than a NUMBER, you could simply add it to a date
p.launch_dt + r.route_duration
If I understand you correctly, you want to add r.route_duration seconds to p.launch_dt? In that case the expression is:
p.launch_dt + (r.route_duration/24/60/60)
Oracle DATE arithmetic works in days, so the divisions by 24, 60 and 60 convert the route_duration value from seconds to days.