Some values may not be available, for example when travelling I do not take scales, and when travelling really light will only have the thermometer.
A clear the value button each set of readings (i.e. one button clears all blood pressure readings) would set the values to a null value (which could be 0), and when the file is written this will be a genuine Null value, i.e. nothing between the commas in the CSV to indicate that the reading was not available.
Some values may not be available, for example when travelling I do not take scales, and when travelling really light will only have the thermometer.
A clear the value button each set of readings (i.e. one button clears all blood pressure readings) would set the values to a null value (which could be 0), and when the file is written this will be a genuine Null value, i.e. nothing between the commas in the CSV to indicate that the reading was not available.