This is an example model for testing spinpack after changes.

# this is for help, in case the autotest fails on the square64 Heisenberg model
# autotesting: make test
cd ./exe;./m_square 8 0 0 8 1 | tee a.def
echo -e "nud=4,60\na0" | tee a.i
/usr/lib64/openmpi/bin/mpiexec -np 1 ./spin_JJ64 -ia.i -ma.def | tee a.o
# paini.overflow WARNINGs because possible use of big numbers
#define MaxSym (8*NN) // 512 enough? 8*8*2*2*2=128
 k_ud * k_T _0_0_0_0

 i060=  16.37564105  16.37564111  17.26864154  17.47227817 cnv= 4 3
 conv=  16.37564105  16.37564111  17.26864154  17.47227817

# problem 2.56 test, no Nw defined, NZXMAX differs
- spin
+ spin_JJ64
- k_ud * k_T _0_0_0     # MaxSym below 512
+ k_ud * k_T _0_0_0_0   # MaxSym = 512
- sum_h12/n1   :  3.798582179*phase(0.000)
+ sum_h12/n1   :  0.00000e+00*phase(0.000)
- conv=  16.37564102  16.82219222  16.82219222  16.82219222
+ conv=  23.99998304  23.99999808  23.99999808  23.99999808 # fixed in v2.56b