Why does the following formula give an answer of 0:
float variable = (15 / 360) * SensorValue;
while converting to a decimal works just fine?
float variable = 0.042 * SensorValue;
Your values on the right in the first case are integers and are being evaluated as integers. You only try to turn it into a float when you plug in for variable on the left. So you’ve got a value round to 0, which you then stick in a float. In the second case, you have a float on the right so the right is being evaluated as a float.
Thanks for the quick reply.
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I also tried creating “variable” as an int instead of float, and that also gave an answer of 0. Thoughts?
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So would my first attempt have worked if I’d said it like so?
float variable = (15.0 / 360.0) * SensorValue
As @callen says, it’s because your’e doing integer math. You can force floating point math a couple of ways. Here’s one:
float variable = (15 / 360.0) * SensorValue;
Int this case, 360.0 is a floating point number, so the dividend will be converted to a float before the division takes place, as will the multiplicand “SensorValue” and all calculations will take place as floating point.
Here’s another way:
float variable = (15 / (float)360) * SensorValue;
That is called “casting.” The 360 is cast as a float; this causes the dividend and multiplicand to be “promoted” to floating point just as in the previous example.
This works as well:
float variable = ((float)15 / 360) * SensorValue;
But this does not:
float variable = (15 / 360) * (float)SensorValue;
That’s exactly what I would expect.
Yes.
When you divide 15 by 360, the whole number part of the answer is zero.
Gotcha. Thanks a ton!