Using Python to realize the derivation, gradient and modulus of two-times function

Source: Internet
Author: User
Tags modulus

To create a function class, the parameters of the constructor function are

Where part is the function of the bias Guide, Var_index is the number of variables, Val represents the values of these variables

The function of diff is to facilitate the derivation of a unary function

In order to facilitate the linear algebra operation of the gradient, the return value is converted to the Numpy.array type when the GRAD function is defined.

#the derivative obtained is an approximate result fromNumPyImport*#Defining function ClassesclassFunction:def __init__(self, _f): Self.fun=_fdefvalue (Self, val):returnSelf.fun (val)#biased Guide    defPart (self, Var_index, Val): a=Self.fun (val) b= A + 1I=0 E= 1E1= 0.1 whileE > 10 * * (-6)orE >e1:e1=e a=b val_=List (val) Val_[var_index]+ = 10 * *i m=Self.fun (VAL_) n=Self.fun (val) b= (m-n)/10 * *I i-= 2e= ABS (b-a)returna#derivation of a unary function    defdiff (Self, val): a=Self.fun (val) b= A + 1I=0 E= 1E1= 0.1 whileE > 10 * * (-6)orE >e1:e1=e a=b val_= val + 10 * *i m=Self.fun (VAL_) n=Self.fun (val) b= (m-n)/10 * *I i-= 2e= ABS (b-a)returna#Seeking gradients    defGrad (Self, val): G=Array (val) forIinchRange (0, g.size): G[i]=Self.part (i, Val)returnArray (g)#die-Finding    defNorm (Self, Val): s=0 forXinchSelf.grad (val): s+ = x * * 2returnsqrt (s)

Using Python to realize the derivation, gradient and modulus of two-times function

Related Article

Contact Us

The content source of this page is from Internet, which doesn't represent Alibaba Cloud's opinion; products and services mentioned on that page don't have any relationship with Alibaba Cloud. If the content of the page makes you feel confusing, please write us an email, we will handle the problem within 5 days after receiving your email.

If you find any instances of plagiarism from the community, please send an email to: info-contact@alibabacloud.com and provide relevant evidence. A staff member will contact you within 5 working days.

A Free Trial That Lets You Build Big!

Start building with 50+ products and up to 12 months usage for Elastic Compute Service

  • Sales Support

    1 on 1 presale consultation

  • After-Sales Support

    24/7 Technical Support 6 Free Tickets per Quarter Faster Response

  • Alibaba Cloud offers highly flexible support services tailored to meet your exact needs.