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我有一個腳本，它不使用隨機化，當我運行它時會給我不同的答案。我希望每次運行腳本時答案都是一樣的。這個問題似乎只發生在某些（病態）輸入數據上。確定性的python腳本以非確定性的方式行爲
該片段來自一種算法，用於爲線性系統計算特定類型的控制器，它主要由做線性代數（矩陣求逆，Riccati方程，特徵值）組成。
顯然，這是我的一個主要擔心，因爲我現在不能相信我的代碼給我正確的結果。我知道結果可能是錯誤的條件不佳的數據，但我期望一貫錯誤。爲什麼我的Windows機器上的回答不總是一樣的？爲什麼Linux的Windows機器不能提供相同的結果？
我使用Python 2.7.9 (default, Dec 10 2014, 12:24:55) [MSC v.1500 32 bit (Intel)] on win 32，Numpy版本1.8.2和Scipy 0.14.0。 （Windows 8,64位）。
代碼如下。我也嘗試在兩臺Linux機器上運行代碼，並且腳本總是給出相同的答案（但機器給出了不同的答案）。一個是運行Python 2.7.8，Numpy 1.8.2和Scipy 0.14.0。第二個是使用Numpy 1.6.1和Scipy 0.12.0運行Python 2.7.3。
我解決了Riccati方程三次，然後打印答案。我期望每次都有相同的答案，而不是我得到序列'1.75305103767e-09; 3.25501787302e-07; 3.25501787302e-07' 。
import numpy as np
import scipy.linalg
matrix = np.matrix
A = matrix([[ 0.00000000e+00, 2.96156260e+01, 0.00000000e+00,
-1.00000000e+00],
[ -2.96156260e+01, -6.77626358e-21, 1.00000000e+00,
-2.11758237e-22],
[ 0.00000000e+00, 0.00000000e+00, 2.06196064e+00,
5.59422224e+01],
[ 0.00000000e+00, 0.00000000e+00, 2.12407340e+01,
-2.06195974e+00]])
B = matrix([[ 0. , 0. , 0. ],
[ 0. , 0. , 0. ],
[ -342.35401351, -14204.86532216, 31.22469724],
[ 1390.44997337, 342.33745324, -126.81720597]])
Q = matrix([[ 5.00000001, 0. , 0. , 0. ],
[ 0. , 5.00000001, 0. , 0. ],
[ 0. , 0. , 0. , 0. ],
[ 0. , 0. , 0. , 0. ]])
R = matrix([[ -3.75632852e+04, -0.00000000e+00, 0.00000000e+00],
[ -0.00000000e+00, -3.75632852e+04, 0.00000000e+00],
[ 0.00000000e+00, 0.00000000e+00, 4.00000000e+00]])
counter = 0
while counter < 3:
counter +=1
X = scipy.linalg.solve_continuous_are(A, B, Q, R)
print(-3449.15531628 - X[0,0])
我numpy的配置是如下print np.show_config()
lapack_opt_info:
libraries = ['mkl_blas95', 'mkl_lapack95', 'mkl_intel_c', 'mkl_intel_thread', 'mkl_core', 'libiomp5md', 'mkl_blas95', 'mkl_lapack95', 'mkl_intel_c', 'mkl_intel_thread', 'mkl_core', 'libiomp5md']
library_dirs = ['c:/Program Files (x86)/Intel/Composer XE 2013 SP1/mkl/lib/ia32', 'C:/Program Files (x86)/Intel/Composer XE 2013 SP1/compiler/lib/ia32']
define_macros = [('SCIPY_MKL_H', None)]
include_dirs = ['c:/Program Files (x86)/Intel/Composer XE 2013 SP1/mkl/include']
blas_opt_info:
libraries = ['mkl_blas95', 'mkl_lapack95', 'mkl_intel_c', 'mkl_intel_thread', 'mkl_core', 'libiomp5md']
library_dirs = ['c:/Program Files (x86)/Intel/Composer XE 2013 SP1/mkl/lib/ia32', 'C:/Program Files (x86)/Intel/Composer XE 2013 SP1/compiler/lib/ia32']
define_macros = [('SCIPY_MKL_H', None)]
include_dirs = ['c:/Program Files (x86)/Intel/Composer XE 2013 SP1/mkl/include']
openblas_info:
NOT AVAILABLE
lapack_mkl_info:
libraries = ['mkl_blas95', 'mkl_lapack95', 'mkl_intel_c', 'mkl_intel_thread', 'mkl_core', 'libiomp5md', 'mkl_blas95', 'mkl_lapack95', 'mkl_intel_c', 'mkl_intel_thread', 'mkl_core', 'libiomp5md']
library_dirs = ['c:/Program Files (x86)/Intel/Composer XE 2013 SP1/mkl/lib/ia32', 'C:/Program Files (x86)/Intel/Composer XE 2013 SP1/compiler/lib/ia32']
define_macros = [('SCIPY_MKL_H', None)]
include_dirs = ['c:/Program Files (x86)/Intel/Composer XE 2013 SP1/mkl/include']
blas_mkl_info:
libraries = ['mkl_blas95', 'mkl_lapack95', 'mkl_intel_c', 'mkl_intel_thread', 'mkl_core', 'libiomp5md']
library_dirs = ['c:/Program Files (x86)/Intel/Composer XE 2013 SP1/mkl/lib/ia32', 'C:/Program Files (x86)/Intel/Composer XE 2013 SP1/compiler/lib/ia32']
define_macros = [('SCIPY_MKL_H', None)]
include_dirs = ['c:/Program Files (x86)/Intel/Composer XE 2013 SP1/mkl/include']
mkl_info:
libraries = ['mkl_blas95', 'mkl_lapack95', 'mkl_intel_c', 'mkl_intel_thread', 'mkl_core', 'libiomp5md']
library_dirs = ['c:/Program Files (x86)/Intel/Composer XE 2013 SP1/mkl/lib/ia32', 'C:/Program Files (x86)/Intel/Composer XE 2013 SP1/compiler/lib/ia32']
define_macros = [('SCIPY_MKL_H', None)]
include_dirs = ['c:/Program Files (x86)/Intel/Composer XE 2013 SP1/mkl/include']
None
（編輯修剪的問題下）
您是否給發生器播種？ http://docs.scipy.org/doc/numpy/reference/generated/numpy.random.seed.html – NPE
我添加了'np.random.seed（0）'作爲代碼的第一行（就在輸入之後），並沒有區別。將更新問題。 – mwmwm
道歉，我以某種方式誤解你的問題，說明代碼*使用隨機化。哎呀。 – NPE