If statement with multiple conditions

I am processing an image in which I have found a blob and I want to compare the location of that blob to the location of a blob in another image using these lines of code:

for j=1:10
  if ((blob(j,4)-50)<centroid(1)<(blob(j,4)+50))
  if ((blob(j,5)-50)<centroid(2)<(blob(j,5)+50))
%more processing code
end
end
end

The variable 'blob' is a table of previous blobs that have been found with their x location in column 4 and the y location in column 5. The code should cycle through the 10 other voids in the table and if their location is within +/- 50 pixels to the new void then some further code is run.

At the moment these if statements seem to be taken as true regardless of what centroid values I put in and I can't see why.

Note that centroid(1) and centroid(2) have been found using regionprops.

Answer 1

[Friedrich]

Hi,

this ((blob(j,4)-50)<centroid(1)<(blob(j,4)+50)) wont work as you might think it will. You need to split it up into

((blob(j,4)-50)<centroid(1)) && (centroid(1)<(blob(j,4)+50))

For the answer to why is that needed see the second half of my answer here:

http://www.mathworks.com/matlabcentral/answers/66844-how-to-add-three-if-else-conditions

[Robert]

Spot on answer, thanks for the help!

[Maryam ARIF]

write a matlab program which takes a number x from user and display the value of the following function f(x)

f(x)= x/a(x) if x<=-1

sqrtx/b(x) if-1<x<10

x^3/2/r(x) otherwise

where a(x)=1 if cosx>0

-1 otherwise

b(x)=1 if sinx>0

-1 otherwise

r(x)=1 ifcosxsinx>0

-1 otherwise

[Maryam ARIF]

plz give me a answer of this question