MATLAB: Using a vector to represent three coefficients.

vector

Hello I was hoping a could get a reality check on a simple code I wrote that was working the other day. I don't know if I'm just fat fingering something now or if it's bugged somewhere but I was able to input a vector and such as [1 2 3] and it would automatically replace [a b c].

function [quadRoots,disc] = Q1_19000046(coeff)
%[quadRoots,disc] = Q1_19000046(coeff);
%Compute quadRoots and disc of quadratic equation for parameters a, b, and
%c
coeff = [a b c];
X = sqrt(b .^2 - 4 .*a .*c);
Y = 2*a;
quadRoots = (-b + X) ./ Y;
disc = (-b - X) ./ Y;
end

Best Answer

function [quadRoots,disc] = Q1_19000046(coeff)
%[quadRoots,disc] = Q1_19000046(coeff);
%Compute quadRoots and disc of quadratic equation for parameters a, b, and
%c
a = coeff(1);
b = coeff(2);
c = coeff(3);
X = sqrt(b .^2 - 4 .*a .*c);
Y = 2*a;
quadRoots = (-b + X) ./ Y;
disc = (-b - X) ./ Y;
end

Related Solutions

MATLAB: I cannot get the function to solve quadratic equations to work. Can anyone help

Put your function code in a file called Q1_15024248.m somewhere on the MATLAB path (e.g., your working directory).

MATLAB: How to get this function to accept one input argument, a vector representing the three coefficients of the quadratic in the order a, b, c

You're on the right track but there's some cleaning up to do (I have only evaluated the syntax).

1) Q1_18035200 is a really bad function name. It looks like it could be a variable so if I were to see Q1_18035200(1:3) I would think you're indexing, not calling a function (it would also be a bad variable name). Also, function names should be descriptive.

2) Your current definitions of a, b, and c require that the user enter a column vector. It's generally a good idea for the code to be more flexible and to allow the user to enter a column or row vector. The lines below will accept either.

a= coeff(1);
b= coeff(2);
c= coeff(3);

3) The first end ends your function and should result in an error when calling your function. Remove it.

This statement is not inside any function.
 (It follows the END that terminates the definition of the function "Q1_18035200".)

4) Make sure you're terminating lines with a semicolon to supress outputs (see the quadRoots line).

5) This line isn't doing anything

 quadRoots - x1;

Best Answer

Related Solutions

MATLAB: I cannot get the function to solve quadratic equations to work. Can anyone help

MATLAB: How to get this function to accept one input argument, a vector representing the three coefficients of the quadratic in the order a, b, c

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