Help with a condition function

[swanley007]

Hello everyone,


I need a little help.

I need a function that will do the following:

I have two variables ( can have more if needed)

If scale is 0-5 then ticks = 5
If scale is 6-10 then ticks = 2.5
If Scale is 11-15 then ticks is 1.25
...AND SO ON.

I would code with conditionals, but It needs to be good forr an unlimited number of scales.

I need to set ticcks based on scale


Thanks

[laserlight]

I would code with conditionals, but It needs to be good forr an unlimited number of scales.

You need to find out how to map the scale to the ticks.
As a hint, notice that:
scale = [0-5] => ticks = 5 / 1
scale = [6-10] => ticks = 5 / 2
scale = [11-15] => ticks = 5 / 4

[swanley007]

So it looks like I could do something like:

i = 0;

for(j = 6;j<=scale;j=j+5)
{
     i++;
}

ticks = 5/(2^i);

Does this seem like it would work?

[7stud]

Does this seem like it would work?

Gee, willickers. Your computer won't explode if you try it.

[iMalc]

You could use the forumla:

ticks = 5.0 / (1 << ((scale-1)/5));

Of course, you'd have to treat the zero case differently, unless you shift your ranges to the more convenient 0-4, 5-9, 10-14, 15-19, ... and get rid of the "-1" above.

[OnionKnight]

(2^i)

This may not do what you're expecting. ^ is the operator for bitwise XOR and not for raising a number to a power. You use the math.h function pow() for that.
But since you're using 2 as a base and integers as exponent you can use left bitwise shifting instead which is very fast but will not give the value expected if shifted out of bonds.
"2^i" in math can be written as "1 << i" in C/C++