Today I was executing code where I wanted to compare a rational to a a
computed list of about 1.8 million rationals. I wanted to be able to
specify two items as input to the program in y, so I coded
if. #y do. lim =. {. y else. lim =. 99r100 end.
and then I had a line where I was comparing it to a long running total of
booleans over a i.
As long as I allowed it to accept the default, the program worked, but when
I specified the value of y from the command line, y got a shape. Then I got
a length error. When I stopped the program in debug, I found that the way I
passed in y to lim, lim ended up having a shape - it was a 1 element array
and not a scalar. In order to compare it using =, I had to do the following:
, lim ="1 (step, 1) $
And that seemed like a lot of manipulation and jumping through hoops.
I did searches and other things, I am not sure I've read it anywhere, but I
think I've seen discussion of it, I just can't find it.
How do you "unarray" a thing? Turn it back into a scalar? Is it something
horrible like ".": ? I didn't think of that this afternoon, and I'm not
sure it would have worked. I probably could have done %/ 2 x: since I
expected the input to be a rational, but I was drawing a blank at the
time...is there an official way to scrub the arrayness off of a variable? A
way to reshape it that scrubs the shape?
--
Of course I can ride in the carpool lane, officer. Jesus is my constant
companion.
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