having trouble with formula for last column ( Axis) the maximum value of the Axis can only be 180. If 100 degrees is added then the value will be 80.
I have steps 1 and 2 which are simple adding formula but I cant work out the formula for step 3 as shown below
Transpose -3.00 +2.00 x 30
Sphere Cylinder Axis
-3.00 +2.00 30
Step 1 Add the sphere and cylinder powers to determine the new sphere power
(-3.00) + (+2.00) = -1.00
Step 2 Change the sign of the cylinder -2.00
Step 3 Change the axis by 90 degrees. (if the axis is 90 or less than 90, add 90 degrees to the axis, if the axis is greater than 90 deduct 90 from the axis) 120 ( this is the step I have having most problem with as the axis can only be 1- 180 , there is no zero as that would be the same as 180)
The transposed prescription is: -1.00 -2.00 x 120
Sphere Cylinder Axis
-1.00 -2.00 120
Any help how I can use a formula for step 3 or a macro function to switch back and fourth between the transposed prescription . Thanks you
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