topic Re: need help identifying first nonzero column in Discussions

need help identifying first nonzero column

dale_lehman — Wed, 13 Dec 2017 16:06:24 GMT

I have a large dataset with around 30 columns of time-dated financial entries. I want to know which column is the first with a nonzero (no columns have missing data, but I want to get the first column with a positive value entry) value. I've attached a small made-up example with four time columns and a fifth column showing what I'd like my formula to result in. If the zero values were missing, I could use the function for Number (number of nonmissing values) to get what I want, but when there is no missing data and zero values, I can't figure out how to automate identifying which column is the first that has a positive value. Any ideas will be appreciated.

Re: need help identifying first nonzero column

uday_guntupalli — Wed, 13 Dec 2017 16:15:21 GMT

@dale_lehman,

Maybe try this ?

dt = Current Data Table();
Mat = dt << Get As Matrix;  
DesList = list(); 
for(i = 1 , i <= N Rows(Mat), i++, 
		Pos = Min(Loc(Mat[i,0])); 
		Insert Into(DesList,Pos);
   );
Show(DesList);

Re: need help identifying first nonzero column

dale_lehman — Wed, 13 Dec 2017 17:02:33 GMT

Thank you - this indeed computes what I want, but I need a bit more help (due to my almost nonexistent JSL abilities). I can see the correct calculations in the log window, but when I enter your script into the formula window for a new column, I get blank values. The warning I get concerns the Show() function. How do I get the resulting calculations to appear in the new formula column?

Re: need help identifying first nonzero column

uday_guntupalli — Wed, 13 Dec 2017 17:36:30 GMT

@dale_lehman,
Couple of thoughts and solutions here to your problem .

Approach 1 : Continue with JSL from previous solution and add it to table

dt = Current Data Table();
Mat = dt << Get As Matrix;  
DesList = list(); 
for(i = 1 , i <= N Rows(Mat), i++, 
		Pos = Min(Loc(Mat[i,0])); 
		Insert Into(DesList,Pos);
   );

dt << New Column("Test",Numeric,Continuous,<< Set Values(DesList));

// Please note that there will be "." missing value if none of your columns have a positive value

Approach 2 : Script the formula in JSL and apply it to the table - a little roundabout - but scaleable - an old but relevant example - will edit later in the day

for(i = 1, i <= N Items(InvColNames), i++,
							If(i == 1,
									Stmt = ":" || InvColNames[i] || " >= 1 &" || ":" || InvColNames[i] || " <= InvLimit" ;
									,
									Stmt = Stmt || " & " || ":" || InvColNames[i] || ">= 1 &" || ":" || InvColNames[i] || " <= InvLimit"  ; 
							  ) ;
					   );
					   
					Eval( Parse( Eval Insert("\[ dt_Inp << New Column("Status_Inv",Numeric,Continuous,Formula(^Stmt^)); ]\" ) ) );

Approach 3 : Manually do something like this - not a fan of this, but can't seem to find an alternative by myself - maybe others will have better thoughts

If(
	:Column 1 > 0, "Column 1",
	:Column 2 > 0, "Column 2",
	"No Positive"
)