get_precipitation_measure: Convert the amount of water found in the graduated cylinder...
In mbask/pluviometer: Precipitation Readings From a Home-made Pluviometer

Description Usage Arguments Value Examples

The amount of water in ml (or g), is converted to l/m2 (or mm) taking into account the pluviometer factor. The function may be used to get the amount of water (in ml) one should find in the cylinder, given the amount of precipitation. This may be useful to mark an ungraduated container with precipitation (mm or l/m2) levels.

1	get_precipitation_measure(water_volume, funnel_area, rain_volume = NULL)

`water_volume`	the volume (in ml) or weight (in g) of the water in the graduated cylinder
`funnel_area`	the internal surface area of the funnel (in cm2) (required)
`rain_volume`	the volume (in mm or l/m2) of precipitation, default to `NULL`

standard rain measure in l/m2 or mm (numeric) when rain_volume is NULL, water volume in ml (numeric) when water_volume is not numeric

# Found 10 ml of water in a pluviometer whose surface area is 20 cm^2
get_precipitation_measure(10, 20)
## Not run: 
# Weight of empty container: 856g
# Weight of container with rainwater: 925g
# Diameter of funnel: 19.6 cm
19.6  %>% 
 get_funnel_area %>% 
 get_precipitation_measure(925-856, .)
# Estimate sprinkler flow on a 5 m radius area, switched
# on for 10 minutes, result in l/m
19.6  %>% 
 get_funnel_area %>% 
 get_precipitation_measure(925-856, .) %>% 
 multiply_by(pi * 5^2) %>% 
 divide_by(10)
 # Inverse calculation
 # How to mark an ungraduated 1 litre cylinder for every 2 mm of rain?
 get_precipitation_measure(
   water_volume = NULL, 
   get_funnel_area(19.6 %>% get_funnel_area), 
   rain_volume = seq(2, 34, 2))
 
## End(Not run)