I have a task where I have to calculate the area of a triangle from degrees 1 to 90, that is bound within a semi circle. I keep getting an error with the last line for some reason
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Beenish Shabir
el 16 de Oct. de 2020
Comentada: Rena Berman
el 7 de Mayo de 2021
I have a task where I have to calculate the area of a triangle from degrees 1 to 90, that is bound within a semi circle. I keep getting an error with the last line for some reason.
radius = rand;
a = 2*radius;
alpha = (1:90)
b = a * cosd(alpha(1:90));
area = 0.5*a*sind(1:90)
triangle= area*b
2 comentarios
Rik
el 19 de Oct. de 2020
I have a task where I have to calculate the area of a triangle from degrees 1 to 90, that is bound within a semi circle. I keep getting an error with the last line for some reason
I have a task where I have to calculate the area of a triangle from degrees 1 to 90, that is bound within a semi circle. I keep getting an error with the last line for some reason.
radius = rand;
a = 2*radius;
alpha = (1:90)
b = a * cosd(alpha(1:90));
area = 0.5*a*sind(1:90)
triangle= area*b
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Image Analyst
el 16 de Oct. de 2020
You need to be using .* instead of * to do an elemenet by element multiplication instead of a matrix multiplication. Try this:
radius = 2 * rand;
alpha = (1:90)
bases = radius * cosd(alpha) % A vector of 90 elements
heights = radius * sind(alpha) % A vector of 90 elements
triangle_areas = 0.5 * bases .* heights % A vector of 90 elements
% For optional fun, plot the area.
plot(alpha, triangle_areas, 'b.-', 'LineWidth', 2);
grid on;
xlabel('Angle', 'FontSize', 18);
ylabel('Area', 'FontSize', 18);
title('Triangle Area vs. Angle', 'FontSize', 18);
2 comentarios
Image Analyst
el 17 de Oct. de 2020
You can Accept only one answer, so accept the best one. However you can also vote for that and the other(s) to award those persons additional reputation points also.
Más respuestas (1)
meghannmarie
el 16 de Oct. de 2020
Editada: meghannmarie
el 16 de Oct. de 2020
You need to use the dot operator if you are doing element wise multiplication (.*). You use just the asterick for matrix multiplication.
triangle= area.*b
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