Error using cross and not calculating correctly

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Commented: Braden on 14 Mar 2023
I am trying to write the code to calculate the area of a trianlge given three vectors. I keep getting an answer that is wrong. Here's the code that I wrote:
input a=['Enter vector a:'];
input b=['Enter vector b:'];
input c=['Enter vector c:'];
A=norm(cross('c-a','b-a'));
Area=A/2
This is what I get when I plug in the following vectors:
>> TAREA
a=['Enter vector a:'][1 2 2]
b=['Enter vector b:'][3 1 4]
c=['Enter vector c:'][5 2 1]
Area =
53.4649
The area should be 5.4083. Why is the code not working properly?

Walter Roberson on 14 Mar 2023
CA = 'c-a'
CA = 'c-a'
BA = 'b-a'
BA = 'b-a'
dCA = double(CA)
dCA = 1×3
99 45 97
dBA = double(BA)
dBA = 1×3
98 45 97
cross(CA,BA)
ans = 1×3
0 -97 45
cross(dCA,dBA)
ans = 1×3
0 -97 45
From this you can see that cross('c-a','b-a') is the same as cross([99 45 97],[98 45 97]) . You are taking the cross-product of the characters ['c' '-' 'a'] and ['b' '-' 'a'] rather than the cross-product of the difference in values of variables c and a and b.
Got it now. Thanks

Dyuman Joshi on 14 Mar 2023
Edited: Dyuman Joshi on 14 Mar 2023
You are using character scalars instead of using variables. The result you get are corresponding to the ascii values of the characters
a=[1 2 2];
b=[3 1 4];
c=[5 2 1];
%Using variables
Area1=norm(cross(c-a,b-a))/2
Area = 5.4083
Area2=norm(cross('c-a','b-a'))/2
A = 53.4649
Got it now. Thanks