Am I doing this right? (a Math formula to Matlab language)

1 次查看（过去 30 天）
BN
BN 2020-2-15
回答： Giuseppe Inghilterra 2020-2-15
I needed to calculate this formula:
So I wrote a function in order to do that:
(P is x and P^ is y):
function NS = nash_sat(x, y)
% This function calculates Nash-Sutcliffe efficiency coefficient
% Detailed explanation goes here
A = sum (x-y).^2;
B = sum (x-(mean(x)).^2;
fraction = (A/B);
NS = 1-fraction;
end
This is the first time I type a math formula in Matlab. I want to know if I typed the formula in the function correctly or not.
Thank you so much.

请先登录，再回答此问题。

采纳的回答

James Tursa
James Tursa 2020-2-15
编辑：James Tursa 2020-2-15
You are on the right track, but have typos in the code due to parentheses issues.
A = sum( (x - y).^2 );
B = sum( (x - mean(x)).^2 );

更多回答（1 个）

Giuseppe Inghilterra
Hi,
A and B terms are wrong.
What you wrote is the square of sum of differences. Instead formula is the sum of square of differences.
The code should be written as follow:
A = sum((x-y).^2);
B = sum((x-(mean(x))).^2);
fraction = (A/B);
NS = 1-fraction;
Pay attention also to space left between "sum" and "(x-y)" in your code: it is not correct.

类别

在 Help Center 和 File Exchange 中查找有关 Get Started with MATLAB 的更多信息

标签

产品


版本

R2018b

Community Treasure Hunt

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

Start Hunting!

Translated by