Unsual gradient from gradient

2018 1 31
1 个回答
回答已采纳
更新时间：2018 2 3
4 次查看（30 天）

0 个投票

Hello, when I try and calculate the gradient I receive slope = gradient (fx)
slope =
(7167*x^2)/25000 - (3523*x)/5000 + 6389/10000
>> GRAD = vpa (slope, 10)
GRAD =
0.28668*x^2 - 0.7046*x + 0.6389
Will someone advised me how to interpret this please? GS.

请先登录，再回答此问题。

 采纳的回答

Star Strider
Star Strider 2018-1-31

1 个投票

The vpa function converts the fractions to their decimal equivalents (decimal fractions).

7 个评论
显示 5更早的评论 隐藏 5更早的评论

Gavin Seddon
Gavin Seddon 2018-2-1
Thank you, to get a single answer must this be calculated?
Star Strider
Star Strider 2018-2-1
My pleasure.
Note that ‘GRAD’ is a function of ‘x’, so if you want a strictly numeric answer, you must provide a value for ‘x’.
Gavin Seddon
Gavin Seddon 2018-2-3
Hello, I followed the intuitive procedure however I received: x=10
x =
10
>> solve slope Warning: Do not specify equations and variables as character vectors. Instead, create symbolic variables with syms. > In solve>getEqns (line 445) In solve (line 225)
ans =
0 thank you, will you direct me further please? GS.
Star Strider
Star Strider 2018-2-3
My pleasure.
Your ‘slope’ expression needs to be defined as a function (available in R2012a and later).
syms x
slope(x) = (7167*x^2)/25000 - (3523*x)/5000 + 6389/10000;
x = 10;
GRAD = vpa(slope(10))
GRAD =
22.2609
Ideally, the expression that created ‘slope’ should be defined as a function. Then ‘slope’ will inherit the function designation, and be a function itself.
Gavin Seddon
Gavin Seddon 2018-2-3
Hello and thank you.
Gavin Seddon
Gavin Seddon 2018-2-3
Hello and thank you.
Star Strider
Star Strider 2018-2-3
As always, my pleasure.

请先登录，再进行评论。

更多回答（0 个）

类别

在 帮助中心 和 File Exchange 中查找有关 Symbolic Math Toolbox 的更多信息

标签

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by