1
我使用lambdify
来编译一个表达式,该表达式是某些参数的函数。每个参数有N
点。所以我需要评估表达N
次。下面显示了一个关于如何完成的简化示例。Python 3:Sympy:包含列表信息以优化lambdify
import numpy as np
from sympy.parsing.sympy_parser import parse_expr
from sympy.utilities.lambdify import lambdify, implemented_function
from sympy import S, Symbol
from sympy.utilities.autowrap import ufuncify
def CreateMagneticFieldsList(dataToSave,equationString,DSList):
expression = S(equationString)
numOfElements = len(dataToSave["MagneticFields"])
#initialize the magnetic field output array
magFieldsArray = np.empty(numOfElements)
magFieldsArray[:] = np.NaN
lam_f = lambdify(tuple(DSList),expression,modules='numpy')
try:
for i in range(numOfElements):
replacementList = np.zeros(len(DSList))
for j in range(len(DSList)):
replacementList[j] = dataToSave[DSList[j]][i]
try:
val = np.double(lam_f(*replacementList))
except:
val = np.nan
magFieldsArray[i] = val
except:
print("Error while evaluating the magnetic field expression")
return magFieldsArray
list={"MagneticFields":list(range(10000)), "Chx":list(range(10000))}
out=CreateMagneticFieldsList(list,"MagneticFields*5+Chx",["MagneticFields","Chx"])
print(out)
有没有方法可以进一步优化此调用?具体来说,我的意思是有没有办法让lambdify
包括我正在计算的点列表,以便循环评估可以优化?
当您使用带有modules =“numpy”的lambdify时,它会创建一个numpy表达式。您应该能够将numpy数组作为参数传递给您的lambdified函数,并且表达式将被矢量化为它们。 – asmeurer
@asmeurer感谢您的信息!我会尝试的! –