# Numerical Constraint Block

## Where Is It?

The numerical constraint block is found in the Number section of the Data Statements drawer of the Blawx toolbox.

## What Does It Do?

The numerical constraint block is used to specify that a numerical value must adhere to an equality, disequality, or comparison restraint.

## Technical Details

The numerical constraint block is a statement, and can be stacked with other statements.

It requires two internal connectors, both of which must be variables or numbers.

It allows the user to choose the restriction to be applied to the left input, relative to the right input, including comparisons (greater than, less than, etc), and equalities and inequalities.

## Tips

The numerical constraint block is a very powerful tool when dealing with numbers that are constrained to be greater, equal to, or less than other numbers.

To perform a mathematical calculation using numerical constraints, you constrain a variable to be equal to the result of a mathematical calculation block.

If a person at least 16 must pay taxes, and a person at least 18 may vote, then we know the age of a person who is required to pay taxes and cannot vote is at least 16 and less than 18. That is a numerical constraint that can be calculated by combining two other numerical constraints.

Through the numerical constrain block, Blawx allows you to express those sorts of rules, and get answers that are expressed as a range like "16 >= Age < 18".