How do I get the exact x value that find-root used

asked 2020-10-22 03:17:45 +0100

cybervigilante
411 ●9 ●30 ●45

updated 2020-10-22 03:27:15 +0100

I was using this simple algorithm to find roots, but it occurred to me that I want the exact x-value at the point where find_root locates the yval. Except I'm only using the last xval. I'm unclear how I could get the actual xval that find_root used when finding the zero.

roots=[]
for xval in [-10..5,step=.1]:
    try:
        yval=find_root(cos(x)-exp(x),xval,xval+.1)
        roots.append((xval,0))
    except:
        pass

edit retag flag offensive close merge delete

add a comment

1 Answer

Sort by » oldest newest most voted

answered 2020-10-22 17:04:00 +0100

Emmanuel Charpentier
7744 ●6 ●50 ●153

The answer(s) of interest is(are) the yval values, the xval values are the bounds of the search interval. If those are the bounds you are interested in, you may try :

roots=[]
for xval in [-10..5, step=.1]:
    try;
        yval = find_root(cos(x)-exp(x), xval, xval+.1
        root.append((xva, yval, xval+.1))
    except:
        pass

which gives you a list of solution bracketed by the search bounds leading to them, but I have trouble seeing the point...

edit flag offensive delete link

add a comment

Your Answer

Please start posting anonymously - your entry will be published after you log in or create a new account.

Add Answer

Question Tools

1 follower

Stats

Asked: 2020-10-22 03:17:45 +0100

Seen: 132 times

Last updated: Oct 22 '20

Copyright Sage, 2010. Some rights reserved under creative commons license. Content on this site is licensed under a Creative Commons Attribution Share Alike 3.0 license.

How do I get the exact x value that find-root used edit

1 Answer