# V03mathfunc.ztst   [plain text]

```# Tests for the module zsh/mathfunc

%prep
if ( zmodload -i zsh/mathfunc ) >/dev/null 2>&1; then
else
ZTST_unimplemented="The module zsh/mathfunc is not available."
fi

%test
# -g makes pi available in later tests
float -gF 5 pi
(( pi = 4 * atan(1.0) ))
print \$pi
0:Basic operation with atan
>3.14159

float -F 5 result
(( result = atan(3,2) ))
print \$result
0:atan with two arguments
>0.98279

print \$(( atan(1,2,3) ))
1:atan can't take three arguments
?(eval):1: wrong number of arguments: atan(1,2,3)

float r1=\$(( rand48() ))
float r2=\$(( rand48() ))
float r3=\$(( rand48() ))
# Yes, this is a floating point equality test like they tell
# you not to do.  As the pseudrandom sequence is deterministic,
# this is the right thing to do in this case.
if (( r1 == r2 )); then
print "Seed not updated correctly the first time"
else
print "First two random numbers differ, OK"
fi
if (( r2 == r3 )); then
print "Seed not updated correctly the second time"
else
print "Second two random numbers differ, OK"
fi
0:rand48 with default initialisation
F:This test fails if your math library doesn't have erand48().
>First two random numbers differ, OK
>Second two random numbers differ, OK

seed=f45677a6cbe4
float r1=\$(( rand48(seed) ))
float r2=\$(( rand48(seed) ))
seed2=\$seed
float r3=\$(( rand48(seed) ))
float r4=\$(( rand48(seed2) ))
# Yes, this is a floating point equality test like they tell
# you not to do.  As the pseudrandom sequence is deterministic,
# this is the right thing to do in this case.
if (( r1 == r2 )); then
print "Seed not updated correctly the first time"
else
print "First two random numbers differ, OK"
fi
if (( r2 == r3 )); then
print "Seed not updated correctly the second time"
else
print "Second two random numbers differ, OK"
fi
if (( r3 == r4 )); then
print "Identical seeds generate identical numbers, OK"
else
print "Indeterminate result from identical seeds"
fi
0:rand48 with pre-generated seed
F:This test fails if your math library doesn't have erand48().
>First two random numbers differ, OK
>Second two random numbers differ, OK
>Identical seeds generate identical numbers, OK

float -F 5 pitest
(( pitest = 4.0 * atan(1) ))
# This is a string test of the output to 5 digits.
if [[ \$pi = \$pitest ]]; then
print "OK, atan on an integer seemed to work"
else
fi
0:Conversion of arguments from integer
>OK, atan on an integer seemed to work

float -F 5 result
typeset str
for str in 0 0.0 1 1.5 -1 -1.5; do
(( result = abs(\$str) ))
print \$result
done
0:Use of abs on various numbers
>0.00000
>0.00000
>1.00000
>1.50000
>1.00000
>1.50000

print \$(( sqrt(-1) ))
1:Non-negative argument checking for square roots.
?(eval):1: math: argument to sqrt out of range

# Simple test that the pseudorandom number generators are producing
# something that could conceivably be pseudorandom numbers in a
# linear range.  Not a detailed quantitative verification.
integer N=10000 isource ok=1
float -F f sum sumsq max max2 av sd
typeset -a randoms
randoms=('f = RANDOM' 'f = rand48()')
for isource in 1 2; do
(( sum = sumsq = max = 0 ))
repeat \$N; do
let \$randoms[\$isource]
(( f > max )) && (( max = f ))
(( sum += f, sumsq += f * f ))
done
(( av = sum / N ))
(( sd = sqrt((sumsq - N * av * av) / (N-1)) ))
(( max2 = 0.5 * max ))
if (( av > max2 * 1.1 )) || (( av < max2 * 0.9 )); then
print "WARNING: average of random numbers is suspicious.
Was testing: \$randoms[\$isource]"
(( ok = 0 ))
fi
if (( sd < max / 4 )); then
print "WARNING: distribution of random numbers is suspicious.
Was testing: \$randoms[\$isource]"
(( ok = 0 ))
fi
done
(( ok ))
0:Test random number generator distributions are not grossly broken
```