The following worksheet assumes that you have a collection of fish images. For each fish image, three characteristic data are stored: the length of the fish, the height at its left end and the height at its highest point of its body.
Since some fish may have been photographed from far away and others from very close, we do not know these data in real world. However, we should somehow to put these data into relation to each other. We create a unit vector with these three data. Hence, it is a unit vector in !

Instructions

1. Have the fish images displayed one after the other and doublecheck the data! Use the red, blue and green segment to determine the three representing numerical informations and enter/check the values in B2 to D5. In B7 down to D10, watch the length of the corresponding unit vectors!
2. Have the unknown testfish displayed. Perform the same measurements and enter the data in B12 to D12.
3. Is the test fish already in the list of known fishes? Look at E17 to E20 and figure out which of the already known fish has the closest unit vector. It has the most similar corresponding characteristics! To get more readable numbers, you may want to look at the cells F17 to F20. They show 100 times the values of their E-neighbors.