Pspice code error for design memristor please solve it

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.subckt memristorplus plus minus PARAMS:
*Parameters' values
+rmin=100 rmax=390 rinit=390 alpha=1E15 beta=10 gamma=0.1 Vtr=1.5 Vtl=-1.5 yo=0.0001
+m=82 fo=310 Lo=5
Gr 0 r value={dr_dt(V(plus)-V(minus))*(st_f(V(plus)-V(minus))*st_f(V(r)-rmin)+
+st_f(-(V(plus)-V(minus)))*st_f(rmax-v(r)))}
Cr r 0 1 IC={rinit}
Raux r 0 1E12
*Current equation Imem = V / R(L)
Gpm plus minus value={(V(plus)-V(minus))/((fo*exp(2*L(V(r))))/L(V(r)))}
*Func. for non-linear threshold-based behavior
.func dr_dt(y)={-alpha*((y-VtL)/(gamma+abs(y-VtL)))*st_f(-y+VtL)-beta*y*st_f(y-VtL)*
+st_f(-y+VtR)-alpha*((y-Vtr)/(gamma+abs(y-VtR)))*st_f(y-VtR)}
*Smoothing function
.func st_f(y)={1/(exp(-y/yo)+1)}
*L(V) function
.func L(y)={Lo-Lo*m/y}
.ends memristorplus

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.subckt memristorminus plus minus PARAMS:
*Parameters' values
+rmin=100 rmax=390 rinit=100 alpha=1E15 beta=10 gamma=0.1 Vtr=-1.5 Vtl=1.5 yo=0.0001
+m=82 fo=310 Lo=5
Gr 0 r value={dr_dt(V(plus)-V(minus))*(st_f(V(plus)-V(minus))*st_f(V(r)-rmin)+
+st_f(-(V(plus)-V(minus)))*st_f(rmax-v(r)))}
Cr r 0 1 IC={rinit}
Raux r 0 1E12
*Current equation Imem = V / R(L)
Gpm plus minus value={(V(plus)-V(minus))/((fo*exp(2*L(V(r))))/L(V(r)))}
*Func. for non-linear threshold-based behavior
.func dr_dt(y)={-alpha*((y-VtL)/(gamma+abs(y-VtL)))*st_f(-y+VtL)-beta*y*st_f(y-VtL)*
+st_f(-y+VtR)-alpha*((y-Vtr)/(gamma+abs(y-VtR)))*st_f(y-VtR)}
*Smoothing function
.func st_f(y)={1/(exp(-y/yo)+1)}
*L(V) function
.func L(y)={Lo-Lo*m/y}
.ends memristorminus

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VS 1 0 DC 3 PWL( 0s 0 0.25s 3 0.5s 0 0.75s -3 1s 0 1.25s 3 1.5s 0 1.75s -3 2s 0 2.25s 3 2.5s 0 2.75s -3 3s 0)  
X1 1 2 memristorplus
X2 2 0 memristorminus
*ANALYSIS
.TRAN   10m  1
 
 
.PROBE
.END