diff --git a/src/IO.f90 b/src/IO.f90
index af59b11b9..193580fcc 100644
--- a/src/IO.f90
+++ b/src/IO.f90
@@ -1251,6 +1251,8 @@ subroutine IO_error(error_ID,el,ip,g,instance,ext_msg)
    msg = 'negative number systems requested'
  case (145_pInt)
    msg = 'too many systems requested'
+ case (146_pInt)
+   msg = 'number of values does not match'
 
 !--------------------------------------------------------------------------------------------------
 ! material error messages and related messages in mesh
diff --git a/src/config.f90 b/src/config.f90
index 441dd953c..c7fd95b43 100644
--- a/src/config.f90
+++ b/src/config.f90
@@ -550,7 +550,7 @@ end function getString
 !> @details for cumulative keys, "()", values from all occurrences are return. Otherwise only all
 !! values from the last occurrence. If key is not found exits with error unless default is given.
 !--------------------------------------------------------------------------------------------------
-function getFloats(this,key,defaultVal,requiredShape)
+function getFloats(this,key,defaultVal,requiredShape,requiredSize)
  use IO, only: &
    IO_error, &
    IO_stringValue, &
@@ -561,7 +561,8 @@ function getFloats(this,key,defaultVal,requiredShape)
  class(tPartitionedStringList), target, intent(in)   :: this
  character(len=*),              intent(in)           :: key
  real(pReal),   dimension(:),   intent(in), optional :: defaultVal
- integer(pInt), dimension(:),   intent(in), optional :: requiredShape
+ integer(pInt), dimension(:),   intent(in), optional :: requiredShape ! not useful (is always 1D array)
+ integer(pInt),                 intent(in), optional :: requiredSize
  type(tPartitionedStringList),  pointer              :: item
  integer(pInt)                                       :: i
  logical                                             :: found, &
@@ -588,6 +589,9 @@ function getFloats(this,key,defaultVal,requiredShape)
  if (.not. found) then
    if (present(defaultVal)) then; getFloats = defaultVal; else; call IO_error(140_pInt,ext_msg=key); endif
  endif
+ if (present(requiredSize)) then
+   if(requiredSize /= size(getFloats)) call IO_error(146,ext_msg=key)
+ endif
 
 end function getFloats
 
@@ -597,7 +601,7 @@ end function getFloats
 !> @details for cumulative keys, "()", values from all occurrences are return. Otherwise only all
 !! values from the last occurrence. If key is not found exits with error unless default is given.
 !--------------------------------------------------------------------------------------------------
-function getInts(this,key,defaultVal,requiredShape)
+function getInts(this,key,defaultVal,requiredShape,requiredSize)
  use IO, only: &
    IO_error, &
    IO_stringValue, &
@@ -608,7 +612,8 @@ function getInts(this,key,defaultVal,requiredShape)
  class(tPartitionedStringList), target, intent(in)   :: this
  character(len=*),              intent(in)           :: key
  integer(pInt), dimension(:),   intent(in), optional :: defaultVal, &
-                                                        requiredShape
+                                                        requiredShape ! not useful (is always 1D array)
+ integer(pInt),                 intent(in), optional :: requiredSize
  type(tPartitionedStringList),  pointer              :: item
  integer(pInt)                                       :: i
  logical                                             :: found, &
@@ -635,6 +640,9 @@ function getInts(this,key,defaultVal,requiredShape)
  if (.not. found) then
    if (present(defaultVal)) then; getInts = defaultVal; else; call IO_error(140_pInt,ext_msg=key); endif
  endif
+ if (present(requiredSize)) then
+   if(requiredSize /= size(getInts)) call IO_error(146,ext_msg=key)
+ endif
 
 end function getInts
 
diff --git a/src/plastic_phenopowerlaw.f90 b/src/plastic_phenopowerlaw.f90
index 053fe958b..531c1946d 100644
--- a/src/plastic_phenopowerlaw.f90
+++ b/src/plastic_phenopowerlaw.f90
@@ -217,9 +217,9 @@ subroutine plastic_phenopowerlaw_init
                                                              config_phase(p)%getFloats('interaction_slipslip'), &
                                                              structure(1:3))
 
-     prm%xi_slip_0            = config_phase(p)%getFloats('tau0_slip',   requiredShape=shape(prm%Nslip))
-     prm%xi_slip_sat          = config_phase(p)%getFloats('tausat_slip', requiredShape=shape(prm%Nslip))
-     prm%H_int                = config_phase(p)%getFloats('h_int',       requiredShape=shape(prm%Nslip), &
+     prm%xi_slip_0            = config_phase(p)%getFloats('tau0_slip',   requiredSize=size(prm%Nslip))
+     prm%xi_slip_sat          = config_phase(p)%getFloats('tausat_slip', requiredSize=size(prm%Nslip))
+     prm%H_int                = config_phase(p)%getFloats('h_int',       requiredSize=size(prm%Nslip), &
                                                                          defaultVal=[(0.0_pReal,i=1_pInt,size(prm%Nslip))])
  
      prm%gdot0_slip           = config_phase(p)%getFloat('gdot0_slip')
@@ -256,7 +256,7 @@ subroutine plastic_phenopowerlaw_init
      prm%gamma_twin_char      = lattice_characteristicShear_twin(prm%Ntwin,structure(1:3),&
                                                             config_phase(p)%getFloat('c/a'))
 
-     prm%xi_twin_0            = config_phase(p)%getFloats('tau0_twin',requiredShape=shape(prm%Ntwin))
+     prm%xi_twin_0            = config_phase(p)%getFloats('tau0_twin',requiredSize=size(prm%Ntwin))
 
      prm%gdot0_twin           = config_phase(p)%getFloat('gdot0_twin')
      prm%n_twin               = config_phase(p)%getFloat('n_twin')