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How to elegantly check if a number is within a range?
Has the advantage that the constraints can be checked at compile time, by static verification of your code and the places that use your code. Using an && expression to join two comparisons is simply the most elegant way to do this.
How to return a value in a certain range?
Select a blank cell, enter formula =VLOOKUP (E2,A2:C8,3, TRUE) into the Formula Bar and then press the Enter key. See screenshot: You can see the given number 5 is in the number range 4-6, then the corresponding value Addin 012 in the adjacent cell is populated into the selected cell immediately as above screenshot showed.
What happens when a number is outside of a range?
The idea is that one of the two factors becomes negative if the number lies outside of the range and zero if the number is equal to one of the bounds: Just to add to the noise here, you could create an extension method:
How to return a value based on a given number?
Note: In the formula, E2 is the cell contains the given number, A2:C8 contains the number range and the value you will return based on the given number, and number 3 means that the value you will return locates in the third column of range A2:C8.
How to determine if a point is in a segment?
Now, given a point p, you can determinate if that point is in a segment (if it is one of the points in the list). For the rest of cases we start by looking if it is inside of the axis aligned bounding box.
How to determine if a set of points is inside the shape?
Now, you need to count the number of segments at the left, and if it odd, the point is inside the shape. It is out otherwise. This can also be done with the segments that are up, or right, or below. I just picked left.
How to determine if a point is inside a polygon?
Well, with a little help of a trick from topology we can determinate if a point is inside or not. This is the same algorithm Windows would use to fill a polygon or polyline (such as deciding what is inside a selected area with free hand in Microsoft Paint). Count the number of segments you have to cross to get to the point from outside.