 # Using Okapi Units

I am working on a project where I would like to pass a sensor value into okapi angle units. My sensor returns a double. How do I convert a double to a QAngle data type?

Edit: I have attached the line of code giving me trouble. “angle” is my double value from the sensor.
`angle = OdomMath::constrainAngle180(angle).convert(degree);`

I believe the issue is that `OdomMath::constrainAngle180` requires a QAngle, not a double as an argument. Multiplying `angle` by `degree` seems to work to me.

``````double angle = 0;
angle = OdomMath::constrainAngle180(angle * degree).convert(degree);
``````
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Yep, to convert a double to a RQuantity you simply do `var * unit`.
`5_m` is just syntactic sugar for `5 * meter`.
This can actually be done automatically via dimensional analysis, basically if you do something similar to the following formula your unit is automatically created:

``````// convert ticks (unitless) to distance (length unit)
QLength distanceTravelled = ticks / 360.0 * 4_in * pi;
``````

In this case, it looks like you are using IMU info, so you will want to annotate the unit that the IMU outputs (probably `degree`) like

``````QAngle angle = sensor.get() * degree;
angle = constrainAngle180(angle);
``````
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