Ana,
I think you can do it using boolean functions, which return a 1
when the condition is true and a 0 when the condition is false.
GT(x,y) will return a 1 if x>y. GE(x,y) will return a 1 if
x>=y.
I didn't try it out to be sure but I think you can write the
following four equations:
cond1 = AND(GT(x,-57),LT(x,-30))
cond2 = AND(GE(x,-30),LT(x,-15))
cond3 = AND(GE(x,-15),LE(x,-5))
Y = cond1*(8E-5x**2-0.0024+0.2385) +
cond2*(0.0001x**2+0.0028x+0.3494) +
cond3*(-0.0001x**2-0.004x+0.3058)
best,
David
On 07/19/2022 04:52, Ana Delgado via
TRNSYS-users wrote:
Hello,
I have an input variable that changes over
time. The most correct way to characterize it is to use a
branch function. I wanted to use the equations feature but it
is giving me lots of errors. Using programming language, my
variable changes like this:
If -57 < x < -30
Y1=8E-5x^2-0.0024+0.2385
End IF
If -30< x<-15
Y2=0.0001x^2+0.0028x+0.3494
End if
If -15< x<-5
Y3=-0.0001x^2-0.004x+0.3058
End if
Do you have any tip on how to do it on
TRNSYS? Also it’s not mandatory to use equations.
Thank you in advance,
Kind Regards,
Ana Delgado, University of Aveiro
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