Operators for Comparing Values
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Prerequisite
Introduction
In the “Operators” group, there are 6 boolean blocks (>, <, ≠, =, ≥, ≤) for comparing between numbers or text strings. For example, you can compare between 3 and 5, or between “apple” and “orange”. The comparison result will be true or false.
Comparing Numbers
You can use the 6 comparison blocks to compare 2 numbers, the same way how you compare numbers in Math.
For example, when you run the block “10 > 5”, it will return “true”. However, if you ask if “5 > 5” or “5 > 10”, you will get a result of “false”.
For a reminder, the ≥ or ≤ blocks will return “true” when the 2 numbers are the same. For example:
Comparing Single Letters
If you are comparing single letters, such as “a” vs “b”, the computer will compare their positions in the list of a to z. For example, “a” is at position 1 in the list, and “b” is at position 2. Since 1 is less than 2, we say “a is less than b”. Obviously, the letter "z’ will be greater than any other letter. Here are some more examples:
Note that it does not matter if a letter is in upper or lower case. All letters are converted to lowercase before being compared. For example:
Comparing Text of One or More Letters
When there is more than one letter, we need to compare the 2 sequences of letters by each letter from left to right.
For example, if we are comparing “cake” vs “cap”:
- Position 1: “c” vs “c”, we get a tie, so we move on to position 2.
- Position 2: “a” vs “a”, we get another tie, so we move on to position 3.
- Position 3: “k” vs “p”. Since k comes earlier in the a to z list, we know “k” is smaller than “p”. Therefore, we can stop here and declare “cake” is less than “cap”.
Here are some more examples:
