qPython QProjection Issues instead of queried data - kdb

I tried writing a Q Code which will allow me to pass parameters however I am getting a results as Qprojection. I tried using
qpython.sync() is returning a QProjection instead of the queried data
but solution isn't working(new to Q/kdb world)
Any ideas on what exactly I should change?
q.sync(
'''{[x;y;z]select from quotestackevent where date within(x;y),sym=z}''',
[np.datetime64('2018-04-14','D'), #start date
np.datetime64('2018-04-14','D'), #end date
np.string_('GBPUSD')])

In Q/KDB the functional format is {......}[x;y;z], with x y z being the arguments. If you have left a blank argument then the function becomes a projection.
qpython allows you to pass python arguments to a q function, with the format being q.sync('{......}',x,y,z).
In your example the square brackets is causing the inputs to be passed as a single array to the function, resulting in a projection. This can be fixed by removing the square bracket.
q.sync('{[x;y;z]select from quotestackevent where date within(x;y),sym=z}', np.datetime64('2018-04-14','D'), np.datetime64('2018-04-14','D'), np.string_('GBPUSD'))
Hope this helps!

Related

Value within a function seems to not be able to detect the local variables and also fails

I want to be able to run something like the following:
f:{[dt] syms:`sym1;eval parse"select from tbl where date = dt, sym=syms"}
f[.z.D]
Given the following :
tbl:([] date:2022.01.01 2022.01.01; Id:1000000 2000000; sym:`sym1`sym2;price:10 20;qty:3 4)
f:{[dt] syms:`sym1; ?[tbl;((=;`date;`dt);(=;`sym;`syms));0b;()]}
f1:{[dt] syms:`sym1; (?) . (tbl;((=;`date;`dt);(=;`sym;`syms));0b;())}
f2:{[dt] syms:`sym1; value (?;tbl;((=;`date;`dt);(=;`sym;`syms));0b;())}
f[.z.D] // works
f1[.z.D] // Gives Error - dt not recognized/out of scope
f2[.z.D] // Gives Error - dt not recognized/out of scope
Value within a function seems to not be able to detect the local variables and surprisingly (?) . also fails. (maybe because this in itself is a function and dt is not defined here?)
Is there any work around for this?
For context, I have a function that takes a select string/functional select, parses it, does some checks and manipulations on the functional form and returns a modified functional form.
I want users to be able to call this function from their own functions and that parameters they have defined in their function can be in the outputted functional form and that functional form can be valued some how.
I don't want users to be forced to pass more variables into my function etc.
What you need to do here is remove the backtick for dt and syms
I would also recommend using a backtick when calling your table name.
Further, you should make sure syms is enlisted if it is only one symbol.
So your function should be:
f:{[dt] syms:(),`sym1; ?[`tbl;((=;`date;dt);(=;`sym;syms));0b;()]}
If you parse your select statement you can see the correct form for functional selects:
q)parse "select from tbl where date=2022.01.01,sym=`sym1"
?
`tbl
,((=;`date;2022.01.01);(=;`sym;,`sym1)) // comma in front of `sym1 means enlist
0b
()
The backtick is not needed as this is a variable, defined in your function, it would be the same as doing:
?[`tbl;((=;`date;2022.01.01);(=;`sym;enlist `sym1));0b;()]
This should allow you to use your function correctly:
q)f[2022.01.01]
date Id sym price qty
---------------------------------
2022.01.01 1000000 sym1 10 3
For more information, see the kx documentation

Using the toInteger function with locale and format parameters

I've got a dataflow with a csv file as source. The column NewPositive is a string and it contains numbers formatted in European style with a dot as thousand seperator e.g 1.019 meaning 1019
If I use the function toInteger to convert my NewPositive column to an int via toInteger(NewPositive,'#.###','de'), I only get the thousand cipher e.g 1 for 1.019 and not the rest. Why? For testing I tried creating a constant column: toInteger('1.019','#.###','de') and it gives 1019 as expected. So why does the function not work for my column? The column is trimmed and if I compare the first value with equality function: equals('1.019',NewPositive) returns true.
Please note: I know it's very easy to create a workaround by toInteger(replace(NewPositive,'.','')), but I want to learn how to use the toInteger function with the locale and format parameters.
Here is sample data:
Dato;NewPositive
2021-08-20;1.234
2021-08-21;1.789
I was able to repro this and probably looks to be a bug to me . I have reported this to the ADF team , will let you know once I hear back from them . You already have a work around please go ahead that to unblock yourself .

How to sort values of a field in a structure in Matlab?

In my code, I have a structure and in a field of it, I want to sort its values.
For instance, in the field of File_Neg.name there are the following values, and They should be sorted as the right values.
File_Neg.name --> Sorted File_Neg.name
'-10.000000.dcm' '-10.000000.dcm'
'-102.500000.dcm' '-12.500000.dcm'
'-100.000000.dcm' '-100.000000.dcm'
'-107.500000.dcm' '-102.500000.dcm'
'-112.500000.dcm' '-107.500000.dcm'
'-110.000000.dcm '-110.000000.dcm'
'-12.500000.dcm' '-112.500000.dcm'
There is a folder that there are some pictures with negative labels in it (above example are labels of pictures). I want to get them in the same order as present in the folder(that's mean the Sorted File_Neg.name). But when running the following code the values of Files_Neg.name load as the above example (left: File_Neg.name), while I want the right form.
I have also seen this and that but they didn't help me.
How to sort values of a field in a structure in Matlab?
Files_Neg = dir('D:\Rename-RealN');
File_Neg = dir(strcat('D:\Rename-RealN\', Files_Neg.name, '\', '*.dcm'));
% when running the code the values of Files_Neg.name load as the above example (left: File_Neg.name)
File_Neg.name:
This answer to one of the questions linked in the OP is nearly correct for the problem in the OP. There are two issues:
The first issue is that the answer assumes a scalar value is contained in the field to be sorted, whereas in the OP the values are char arrays (i.e. old-fashioned strings).
This issue can be fixed by adding 'UniformOutput',false to the arrayfun call:
File_Neg = struct('name',{'-10.000000.dcm','-102.500000.dcm','-100.000000.dcm','-107.500000.dcm','-112.500000.dcm','-110.000000.dcm','-12.500000.dcm'},...
'folder',{'a','b','c','d','e1','e2','e3'});
[~,I] = sort(arrayfun(#(x)x.name,File_Neg,'UniformOutput',false));
File_Neg = File_Neg(I);
File_Neg is now sorted according to dictionary sort (using ASCII letter ordering, meaning that uppercase letters come first, and 110 still comes before 12).
The second issue is that OP wants to sort according to the magnitude of the number in the file name, not using dictionary sort. This can be fixed by extracting the value in the anonymous function applied using arrayfun. We use str2double on the file name, minus the last 4 characters '.dcm':
[~,I] = sort(arrayfun(#(x)abs(str2double(x.name(1:end-4))),File_Neg));
File_Neg = File_Neg(I);
Funnily enough, we don't want to use 'UniformOutput',false any more, since the anonymous function now returns a scalar value.

SSRS - How to Sum values on a LookUpSet expression

Hi I have a column that uses a lookupset expression =Join(LookupSet(Fields!ReportUNC.Value, Fields!ReportUNC.Value, Format(Fields!cntSelfService.Value, "###,#######0"), "ExecutionCount")).I'm getting an incorrect parameter when I sum that expression to =Join(Sum(LookupSet(Fields!ReportUNC.Value, Fields!ReportUNC.Value, Format(Fields!cntSelfService.Value, "###,#######0")), "ExecutionCount")). The column to sum is cntSelfService. Please advise.
You have a few different issues with your expression.
When you use the FORMAT function, the result is a string, not a
number.
JOIN is used to concatenate strings from a table into a
single string which wouldn't help your issue.
SUM will not work with a LookupSet
Unfortunately, there's not a built-in way to sum values from a LookupSet.
Luckily, users have had this issue for a while and someone created a function in Visual BASIC SumLookUp that will add the values from a lookupset. You add the code in the Report Properties --> Code tab.
Your expression would be:
=CODE.SumLookup(LookupSet(Fields!ReportUNC.Value, Fields!ReportUNC.Value, Fields!cntSelfService.Value, "ExecutionCount"))
See the code in: Need help in calculation using two Datasets using Expression SSRS

set threshold as a function of autoThreshold

I have written a macro for ImageJ/FIJI to deconvolve my confocal microscopy images and run the "3D Object Counter" plugin. The macro successfully runs all required commands and saves all required data in the specified places.
However, I have found that the 3D-OC autothreshold (as shown in the plugin dialog box) is to stringent resulting in objects being lost or divided.
To remedy this I would like to reduce the autothreshold by a predetermined function something similar to what was done here (from:How to get threshold value used by auto threshold Plugin) which resulted in this code:
setAutoThreshold();
getThreshold(lower,upper);
v=setThreshold(lower,upper*0.5);
run("3D Objects Counter", "threshold="v" slice=10 min.=400 max.=20971520 objects statistics summary");
The idea was to call the AutoThreshold values, modify them and set them to a variable. However when these lines are run the following error is returned:
Number or numeric function expected in line 3.
v=<setThreshold>(lower,upper*0.5);
And if the variable is inserted directly into the threshold key for run(3D-OC) the following msg is encountered:
Numeric value expected in run() function
Key:"threshold"
Value or variable name:"setThreshold(lower,upper*0.5"
Any suggestions or help on how to designate the 3D-OC threshold value as a variable as described would be greatly appreciated (as would any work arounds of course :) ).
Cheers
Edit: After testing Jan's response below (which works perfectly), it appears I need to call the threshold set by the 3D-OC plugin. Anyone know how to do this?
The getThreshold(lower, upper) function returns the lower and upper threshold levels in the provided variables. There is no need to assign any value to a new variable, and as you observed, setThreshold does not have any return value.
Instead, you can use the value(s) returned from getThreshold and use them as parameters in the run method (in the correct way, by string concatenation, see here):
setAutoThreshold();
getThreshold(lower, v);
run("3D Objects Counter", "threshold=" + v + " slice=10 min.=400 max.=20971520 objects statistics summary");
Alternatively, you can use &v in the second parameter to avoid string concatenation in the last line (see the documentation for the run() macro function):
run("3D Objects Counter", "threshold=&v slice=10 min.=400 max.=20971520 objects statistics summary");
You might have to use the lower instead of the upper threshold value, depending on whether you count bright or dark objects.