if(sign(D)!=sign(D[i+1]),--,0)

if(sign(D)!=sign(D[i+1]),0/0,0)

quote:

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Originally posted by YimingChen

try this:

if(sign(D)!=sign(D[i+1]),0/0,0)

James

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quote:

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Originally posted by cpyang

"--" is not a valid numeric expression, it is what we show in results for a missing value. Sure we can improve that particular function so any invalid text entered should resolve into a missing value so most likely that function didn't do that.

You can also use a function to indicate missing value, like NA().

0/0 is the way we used in most places as an expression that will resolve into a missing value.

CP

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