在 Python 中为您创建了非常庞大但非常快速的解决方案。z3它应该比任何做类似事情的 Mathematica 代码或 -solver 代码解决得更快。当然，在预计算阶段之后，它只完成一次，然后可以在多次运行中重复使用（它们将所有计算数据保存到缓存文件中）。
以下解决方案进行了两次预计算。第一个需要几分钟，它预先计算 2.7 GB 的文件，这是一个大的正方形过滤器。这个尺寸是可调整的，可以更小。该文件仅计算一次（除非您更改设置）并在每次运行时重复使用。这种预计算是单核的（但经过一些努力，我可以使它成为多核）。
第二个预计算需要更多时间，这个是多核的，它使用所有 CPU 内核。此预计算生成的文件非常小，即使对于较大的参数值也不到 1 GB。该预计算表存储所有可能的具有整数边的毕达哥拉斯直角三角形。
对所有小于limit尺寸的导管进行预计算。将当前设置更改limit = 100_000为更大的值，在您的情况下可能为 1M。如果这个表太小，那么它将无法为大型导管找到一些解决方案。预先计算的表也存储在磁盘上，并在每次运行时重复使用（不再计算）。
第二个预计算计算以下直角三角形表。它遍历所有可能的第一个整数cathetus A（达到限制）并找到所有可能的第二个整数cathetus B（达到限制）使得A^2 + B^2 = C^2，其中C 也是整数。然后对于每个 A，它存储一组满足该方程的 B。C 没有被存储，因为它可以很容易地从 A 和 B 中计算出来。
为了快速搜索 B，我构建了两个过滤器。例如，我们有任何整数 K0 和 K1。我们可以很容易地看出，如果 X 是一个正方形，那么 X % K0 是一个正方形，X % K1 也是一个正方形。因此，我们可以构建一个大小为 K0 的表，如果 table[X % K0] 是平方模 K0 则为 1，否则为 0。这为我们提供了一个快速过滤器，用于删除所有此类绝对非正方形的 X（即 table[X % K0] 为 0）。第二个 K1 滤波器用于第二阶段的额外滤波。
以下 Python 代码可以立即运行，无需依赖，它会自动从您的 GitHub 获取 STU 文件并将其缓存在磁盘上。
完成上述两次预计算后，所有数千个 s/t/u 解决方案都在 1-2 秒内计算完毕。最后，所有解决方案都以 JSON 格式存储到文件stu_solutions.100000中。
找到的几乎解决方案（具有非整数 Z）可以通过命令转储：
cat stu_solutions.100000 | grep false
找到的精确解（整数 Z）可以通过命令转储：
cat stu_solutions.100000 | grep true
该文件的其余行包含有错误的解决方案（如果表对他们来说太小），或者在找不到 w、x、y 时包含零解决方案。如果出现错误，您必须通过设置更大的limit = ....
有必要设置至少与 一样大的限制Max(Sqrt(s), Sqrt(t))。但最好将其设置为大几倍。表越大，找到所有可能的解决方案的机会就越高。限制最多需要尽可能大w。
要运行以下 Python 代码，您必须安装一次性 PIP 包python -m pip install numba numpy requests。
在线尝试！
numba = None
import numba
import json, multiprocessing, time, timeit, os, math, numpy as np
if numba is None:
class NumbaInt:
def __getitem__(self, key):
return None
class numba:
uint8, uint16, uint32, int64, uint64 = [NumbaInt() for i in range(5)]
def njit(*pargs, **nargs):
return lambda f: f
def prange(*pargs):
return range(*pargs)
class types:
class Tuple:
def __init__(self, *nargs, **pargs):
pass
def __call__(self, *nargs, **pargs):
pass
class objmode:
def __init__(self, *pargs, **nargs):
pass
def __enter__(self):
return self
def __exit__(self, ext, exv, tb):
pass
@numba.njit(cache = True, parallel = True)
def create_filters():
Ks = [np.uint32(e) for e in [2 * 2 * 3 * 5 * 7 * 11 * 13, 17 * 19 * 23 * 29 * 31 * 37]]
filts = []
for i in range(len(Ks)):
K = Ks[i]
filt = np.zeros((K,), dtype = np.uint8)
block = 1 << 25
nblocks = (K + block - 1) // block
for j0 in numba.prange(nblocks):
j = j0 * block
a = np.arange(j, min(j + block, K)).astype(np.uint64)
a *= a; a %= K
filt[a] = 1
idxs = np.flatnonzero(filt).astype(np.uint32)
filts.append((K, filt, idxs))
print(f'filter {i} ratio', round(len(filts[-1][2]) / K, 4))
return filts
@numba.njit('u2[:, :, :](u4, u4[:])', cache = True, parallel = True, locals = dict(
t = numba.uint32, s = numba.uint32, i = numba.uint32, j = numba.uint32))
def filter_chain(K, ix):
assert len(ix) < (1 << 16)
ix_rev = np.full((K,), len(ix), dtype = np.uint16)
for i, e in enumerate(ix):
ix_rev[e] = i
r = np.zeros((len(ix), K, 2), dtype = np.uint16)
print('filter chain pre-computing...')
for i in numba.prange(K):
if i % 5000 == 0 or i + 1 >= K:
with numba.objmode():
print(f'{i}/{K}, ', end = '', flush = True)
for j, x in enumerate(ix):
t, s = i, x
while True:
s += 2 * t + 1; s %= K
t += 1
if ix_rev[s] < len(ix):
assert t - i < (1 << 16)
assert t - i < K
r[j, i, 0] = ix_rev[s]
r[j, i, 1] = np.uint16(t - i)
break
print()
return r
def filter_chain_create_load(K, ix):
fname = f'filter_chain.{K}'
if not os.path.exists(fname):
r = filter_chain(K, ix)
with open(fname, 'wb') as f:
f.write(r.tobytes())
with open(fname, 'rb') as f:
return np.copy(np.frombuffer(f.read(), dtype = np.uint16).reshape(len(ix), K, 2))
@numba.njit(
#'void(i8, i8, u4, u1[:], u4[:], u2[:, :, :], u4, u1[:])',
numba.types.Tuple([numba.uint64[:], numba.uint32[:]])(
numba.int64, numba.int64, numba.uint32, numba.uint8[:],
numba.uint32[:], numba.uint16[:, :, :], numba.uint32, numba.uint8[:]),
cache = True, parallel = True,
locals = dict(x = numba.uint64, Atpos = numba.uint64, Btpos = numba.uint64, bpos = numba.uint64))
def create_table(limit, cpu_count, k0, f0, fi0, fc0, k1, f1):
print('Computing tables...')
def gen_squares_candidates_A(cnt, lim, off, t, K, f, fi, fc):
mark = np.zeros((np.int64(K),), dtype = np.uint8)
while True:
start_s = np.int64((np.int64(off) + np.int64(t) ** 2) % K)
tK = np.uint32(np.int64(t) % np.int64(K))
if mark[tK]:
return np.zeros((0,), dtype = np.uint32)
mark[tK] = 1
if f[start_s]:
break
t += 1
j = np.int64(np.searchsorted(fi, start_s))
assert fi[j] == start_s
r = np.zeros((np.int64(cnt),), dtype = np.uint32)
r[0] = t
rpos = np.int64(1)
tK = np.uint32(np.int64(t) % np.int64(K))
while True:
j, dt = fc[j, tK]
t += dt
tK += dt
if tK >= np.uint32(K):
tK -= np.uint32(K)
if t >= lim:
return r[:rpos]
if np.int64(rpos) >= np.int64(r.shape[0]):
r = np.concatenate((r, np.zeros_like(r)), axis = 0)
assert rpos < len(r)
r[rpos] = t
rpos += 1
def gen_squares(cnt, lim, off, t, K, f, fi, fc, k1, f1):
def is_square(x):
assert x >= 0
if not f1[np.int64(x) % np.uint32(k1)]:
return False
root = np.uint64(math.sqrt(np.float64(x)) + 0.5)
return root * root == x
rA = gen_squares_candidates_A(cnt, lim, off, t, K, f, fi, fc)
r = np.zeros_like(rA)
rpos = np.int64(0)
for t in rA:
if not is_square(np.int64(off) + np.int64(t) ** 2):
continue
assert np.int64(rpos) < np.int64(r.shape[0])
r[rpos] = t
rpos += 1
return r[:rpos]
with numba.objmode(gtb = 'f8'):
gtb = time.time()
search_start = 2
cnt_limit = max(1 << 4, round(pow(limit, 0.66)))
nblocks2 = cpu_count * 8
nblocks = nblocks2 * 64
block = (limit + nblocks - 1) // nblocks
At = np.zeros((limit + 1,), dtype = np.uint64)
Bt = np.zeros((0,), dtype = np.uint32)
Atpos, Btpos = search_start + 1, 0
with numba.objmode(tb = 'f8'):
tb = time.time()
for iMblock in range(0, nblocks, nblocks2):
cur_blocks = min(nblocks, iMblock + nblocks2) - iMblock
As = np.zeros((cur_blocks, block), dtype = np.uint64)
As_size = np.zeros((cur_blocks,), dtype = np.uint64)
Bs = np.zeros((cur_blocks, 1 << 16,), dtype = np.uint32)
Bs_size = np.zeros((cur_blocks,), dtype = np.uint64)
for iblock in numba.prange(cur_blocks):
iblock0 = iMblock + iblock
begin, end = max(search_start, iblock0 * block), min(limit, (iblock0 + 1) * block)
begin = min(begin, end)
#a = np.zeros((block,), dtype = np.uint64)
#b = np.zeros((1 << 10,), dtype = np.uint32)
bpos = 0
for ix, x in enumerate(range(begin, end)):
s = gen_squares(cnt_limit, limit, x ** 2, search_start, k0, f0, fi0, fc0, k1, f1)
assert not (np.int64(bpos) + np.int64(s.shape[0]) > np.int64(Bs[iblock].shape[0]))
#while np.int64(bpos) + np.int64(s.shape[0]) > np.int64(b.shape[0]):
# b = np.concatenate((b, np.zeros_like(b)), axis = 0)
bpos_end = bpos + s.shape[0]
Bs[iblock, bpos : bpos_end] = s
As[iblock, ix] = bpos_end
bpos = bpos_end
As_size[iblock] = end - begin
Bs_size[iblock] = bpos
for iblock, (cA, cB) in enumerate(zip(As, Bs)):
cA = cA[:As_size[iblock]]
cB = cB[:Bs_size[iblock]]
assert Atpos + cA.shape[0] <= At.shape[0]
prevA = At[Atpos - 1]
for e in cA:
At[Atpos] = prevA + e
Atpos += 1
#while np.int64(Btpos) + np.int64(cB.shape[0]) > np.int64(Bt.shape[0]):
#Bt = np.concatenate((Bt, np.zeros_like(Bt)), axis = 0)
#Bt = np.concatenate((Bt, np.zeros(Bt.shape, dtype = np.uint32)), axis = 0)
#assert np.int64(Btpos) + np.int64(cB.shape[0]) <= np.int64(Bt.shape[0])
#assert cB.shape[0] > 0
#Bt[Btpos : Btpos + cB.shape[0]] = cB
Bt = np.concatenate((Bt, cB))
#Btpos += cB.shape[0]
#assert At[Atpos - 1] == Btpos
assert At[Atpos - 1] == Bt.shape[0]
with numba.objmode(tim = 'f8'):
tim = max(0.001, round(time.time() - tb, 3))
print(f'{str(min(limit, (iMblock + cur_blocks) * block) >> 10).rjust(len(str(limit >> 10)))}/{limit >> 10} K, ELA',
round(tim / 60.0, 1), 'min, ETA', round((nblocks - (iMblock + cur_blocks)) * (tim / (iMblock + cur_blocks)) / 60.0, 1), 'min')
assert Atpos == At.shape[0]
with numba.objmode(gtb = 'f8'):
gtb = time.time() - gtb
print(f'Tables sizes: A {Atpos}, B {Bt.shape[0]}')
print('Time elapsed computing tables:', round(gtb / 60.0, 1), 'min')
return At, Bt
def table_create_load(limit, *pargs):
fnameA = f'right_triangles_table.A.{limit}'
fnameB = f'right_triangles_table.B.{limit}'
if not os.path.exists(fnameA) or not os.path.exists(fnameB):
A, B = create_table(limit, *pargs)
with open(fnameA, 'wb') as f:
f.write(A.tobytes())
with open(fnameB, 'wb') as f:
f.write(B.tobytes())
del A, B
with open(fnameA, 'rb') as f:
A = np.copy(np.frombuffer(f.read(), dtype = np.uint64))
assert A.shape[0] == limit + 1, (fnameA, A.shape[0], limit + 1)
with open(fnameB, 'rb') as f:
B = np.copy(np.frombuffer(f.read(), dtype = np.uint32))
assert A[-1] == B.shape[0], (fnameB, A[-1], B.shape[0])
print(f'Table A size {A.shape[0]}, B size {B.shape[0]}')
return A, B
def find_solutions(tA, tB, stu):
def is_square(x):
root = np.uint64(math.sqrt(np.float64(x)) + 0.5)
return bool(root * root == x), int(root)
assert tA[-1] == tB.shape[0]
fname = f'stu_solutions.{tA.shape[0] - 1}'
with open(fname, 'w', encoding = 'utf-8') as fout:
for s, t, u in stu:
s, t, u = map(int, (s, t, u))
r = {'stu': [s, t, u]}
if s + 1 >= tA.shape[0]:
r['err'] = f's {s} exceeds table A len {tA.shape[0]}'
elif t + 1 >= tA.shape[0]:
r['err'] = f't {t} exceeds table A len {tA.shape[0]}'
else:
r['res'] = []
bs = tB[tA[s] : tA[s + 1]]
ts = tB[tA[t] : tA[t + 1]]
for w in np.intersect1d(bs, ts):
w = int(w)
x2 = s ** 2 + w ** 2
y2 = t ** 2 + w ** 2
x_isq, x = is_square(x2)
assert x_isq, (s, t, u, w, x2)
y_isq, y = is_square(y2)
assert y_isq, (s, t, u, w, x2, y2)
z2 = u ** 2 + y2
z_isq, z = is_square(z2)
r['res'].append({
'w': w,
'x': x,
'y': y,
'z2': z2,
'z2_is_square': z_isq,
'z': z if z_isq else math.sqrt(z2),
})
fout.write(json.dumps(r, ensure_ascii = False) + '\n')
print(f'STU solutions written to {fname}')
def solve(limit):
import requests
filts = create_filters()
fc0 = filter_chain_create_load(filts[0][0], filts[0][2])
tA, tB = table_create_load(limit, multiprocessing.cpu_count(),
filts[0][0], filts[0][1], filts[0][2], fc0, filts[1][0], filts[1][1])
# https://github.com/Sultanow/pythagorean/blob/main/data/pythagorean_stu_Arty_.txt?raw=true
ifname = 'pythagorean_stu_Arty_.txt'
iurl = f'https://github.com/Sultanow/pythagorean/blob/main/data/{ifname}?raw=true'
if not os.path.exists(ifname):
print(f'Downloading: {iurl}')
data = requests.get(iurl).content
with open(ifname, 'wb') as f:
f.write(data)
stu = []
with open(ifname, 'r', encoding = 'utf-8') as f:
for line in f:
if not line.strip():
continue
if 'elapsed' in line:
continue
s, t, u, *_ = eval(f'[{line}]')
stu.append([s, t, u])
print(f'Read {len(stu)} s/t/u tuples')
find_solutions(tA, tB, stu)
def main():
limit = 100_000
solve(limit)
if __name__ == '__main__':
main()
输出：
filter 0 ratio 0.0224
filter 1 ratio 0.0199
Table A size 100001, B size 371720
Read 27060 s/t/u tuples
STU solutions written to stu_solutions.100000
对于 50K 限制，所有找到的几乎解决方案的示例（其中只有 Z 不是整数）：
{"stu": [3528, 37128, 10175], "res": [{"w": 31654, "x": 31850, "y": 48790, "z2": 2483994725, "z2_is_square": false, "z": 49839.69025786577}]}
{"stu": [7700, 12155, 5460], "res": [{"w": 10608, "x": 13108, "y": 16133, "z2": 290085289, "z2_is_square": false, "z": 17031.89035309939}]}
{"stu": [9405, 12155, 10608], "res": [{"w": 5460, "x": 10875, "y": 13325, "z2": 290085289, "z2_is_square": false, "z": 17031.89035309939}]}
{"stu": [11760, 18564, 31977], "res": [{"w": 13475, "x": 17885, "y": 22939, "z2": 1548726250, "z2_is_square": false, "z": 39353.8594041296}]}
{"stu": [14364, 18564, 13475], "res": [{"w": 31977, "x": 35055, "y": 36975, "z2": 1548726250, "z2_is_square": false, "z": 39353.8594041296}]}
{"stu": [15400, 24310, 10920], "res": [{"w": 21216, "x": 26216, "y": 32266, "z2": 1160341156, "z2_is_square": false, "z": 34063.78070619878}]}
{"stu": [18480, 29172, 13104], "res": [{"w": 21175, "x": 28105, "y": 36047, "z2": 1471101025, "z2_is_square": false, "z": 38354.93481939449}]}
{"stu": [18810, 24310, 21216], "res": [{"w": 10920, "x": 21750, "y": 26650, "z2": 1160341156, "z2_is_square": false, "z": 34063.78070619878}]}
{"stu": [21840, 43500, 30800], "res": [{"w": 14651, "x": 26299, "y": 45901, "z2": 3055541801, "z2_is_square": false, "z": 55276.95542448046}]}
{"stu": [22572, 29172, 21175], "res": [{"w": 13104, "x": 26100, "y": 31980, "z2": 1471101025, "z2_is_square": false, "z": 38354.93481939449}]}
{"stu": [23100, 36465, 16380], "res": [{"w": 31824, "x": 39324, "y": 48399, "z2": 2610767601, "z2_is_square": false, "z": 51095.67105929816}]}
{"stu": [23520, 37128, 63954], "res": [{"w": 26950, "x": 35770, "y": 45878, "z2": 6194905000, "z2_is_square": false, "z": 78707.7188082592}]}
{"stu": [28215, 36465, 31824], "res": [{"w": 16380, "x": 32625, "y": 39975, "z2": 2610767601, "z2_is_square": false, "z": 51095.67105929816}]}
{"stu": [30800, 48620, 21840], "res": [{"w": 42432, "x": 52432, "y": 64532, "z2": 4641364624, "z2_is_square": false, "z": 68127.56141239755}]}
{"stu": [36960, 37128, 31654], "res": [{"w": 10175, "x": 38335, "y": 38497, "z2": 2483994725, "z2_is_square": false, "z": 49839.69025786577}]}
{"stu": [37620, 43500, 14651], "res": [{"w": 30800, "x": 48620, "y": 53300, "z2": 3055541801, "z2_is_square": false, "z": 55276.95542448046}]}
{"stu": [37620, 48620, 42432], "res": [{"w": 21840, "x": 43500, "y": 53300, "z2": 4641364624, "z2_is_square": false, "z": 68127.56141239755}]}