error about randomVariablePositioner

[bridger]

OpenSees 2.3.1
error is:
ERROR: Illegal random variable specification in random
variable positioner command.

while executing
"randomVariablePositioner $rvTag -rvTag $rvTag -parameter $param($rvTag)"
("foreach" body line 2)
invoked from within
"foreach rvTag [array names param] {
randomVariablePositioner $rvTag -rvTag $rvTag -parameter $param($rvTag)
}"
(file "cantilever.tcl" line 44)

code as follows:
wipe
model BasicBuilder -ndm 2 -ndf 3
set b 0.1; set d 0.5
set E 2.0e8; set fy 4.1e5
set secTag 2
uniaxialMaterial Hardening 4 $E $fy 0 [expr 0.02/(1-0.02)*$E]
section WFSection2d 2 4 $d $b $b 0 20 0
geomTransf Corotational 1
set L 5.0; set Nele 5; set dL [expr $L/$Nele]
node 0 0.0 0.0; fix 0 1 1 1
for {set e 1} {$e <= $Nele} {incr e} {
node $e [expr $e*$dL] 0.0
element dispBeamColumn $e [expr $e-1] $e 1 Legendre $secTag 2
}
reliability
parameter 1
parameter 4
parameter 10
for {set e 1} {$e <= $Nele} {incr e} {
addToParameter 1 element $e fy
addToParameter 4 element $e E
addToParameter 10 element $e d
}
parameter 5 node $Nele coord 1
parameter 8 loadPattern 1 loadAtNode $Nele 2
set Pmax 1710
randomVariable 1 lognormal $E [expr 0.05*$E]; set param(1) 4
randomVariable 2 lognormal $fy [expr 0.1*$fy]; set param(2) 1
randomVariable 3 normal $Pmax [expr 0.15*$Pmax]; set param(3) 8
randomVariable 4 normal $L [expr 0.02*$L]; set param(4) 5
randomVariable 5 normal $d [expr 0.04*$d]; set param(5) 10
foreach rvTag [array names param] {
randomVariablePositioner $rvTag -rvTag $rvTag -parameter $param($rvTag)
}