# Printing Colon Values in a Vector

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Jake Bolanski on 20 Oct 2011
Hello,
I am having a little trouble printing out colon values in a vector. For example:
for x = 1:10
y(x) = x
end
This seems to work for me. However, what if the values for x do not start with 1?
For example what I have right now is this:
for x= 23:78
y(x) = x
end
This produces a result like [0 0 0 ... 23 24 25 ... 78]. What I want to be able to do is start with 23 and end at 78 without the 0's; hence: [23 24 25 ... 77 78]. Any advice?
Thanks.
Also,
I am having a little trouble obtaining the mean values for y_coordinates in a rectangle. Currently, I am able to plot a rectangle about the centroid of a flower. What I want to do is use the impixel() command to obtain the RGB values - such that I can know the color. Since the x_values in the rectangle are same as the y_values change, mean(x_cood:x_cood + width) seems to work for me. However, I am unable to present the same for the y_cood. In other words, I want to be able to take the mean of all the y_coordindates at the x_coordinates such that I have an average of all the values within the rectangle. Then, I want to run the impixel() command. Here is what I have:
for U = 1:5:height
% plot(x_cood:x_cood + width,y_cood + U,...
% '--rs','LineWidth',2,...
% 'MarkerEdgeColor','k',...
% 'MarkerFaceColor','r',...
% 'MarkerSize',2)
% hold on;
x_mean = mean(x_cood:x_cood + width);
y_mean = mean(y_cood + U);
plot(x_mean,y_mean,...
'--rs','LineWidth',2,...
'MarkerEdgeColor','k',...
'MarkerFaceColor','r',...
'MarkerSize',2)
hold on;
rect_pixel = impixel(cam_image_rgb,x_mean,y_mean);
r = rect_pixel(1);
g = rect_pixel(2);
b = rect_pixel(3);
fprintf('Red = %0.2f, Green = %0.2f, Blue = %0.2f\n',r,g,b)
end
##### 1 CommentShowHide None
Fangjun Jiang on 20 Oct 2011
Please ask one question at a time. After all, somebody else might search for a topic for answers.

Fangjun Jiang on 20 Oct 2011
It is a matter of an offset, right?
Original:
for x= 23:78
y(x) = x
end
Can be done as:
for x= 23:78
y(x-22) = x
end
Or: y=23:78
##### 1 CommentShowHide None
Jake Bolanski on 20 Oct 2011
Thanks! On a separate note, do you know if it is possible for me to tell the color using RGB values in MatLab? Currently I have r = 243, g = 246, b = 77. Is it possible to say this falls in the yellow category?