Calculate predicted environmental concentrations in surface water due to drift

@@ -57,7 +48,7 @@ with input via spray drift.
PEC_sw_drift(
   rate,
   applications = 1,
-  water_depth = 30,
+  water_depth = as_units("30 cm"),
   drift_percentages = NULL,
   drift_data = c("JKI", "RF"),
   crop_group_JKI = c("Ackerbau", "Obstbau frueh", "Obstbau spaet", "Weinbau frueh",
@@ -66,7 +57,7 @@ with input via spray drift.
     "fruit, early", "aerial"),
   distances = c(1, 5, 10, 20),
   formula = c("Rautmann", "FOCUS"),
-  water_width = 100,
+  water_width = as_units("100 cm"),
   side_angle = 90,
   rate_units = "g/ha",
   PEC_units = "µg/L"
@@ -75,71 +66,78 @@ with input via spray drift.
 
     
     Arguments
-    rate
-Application rate in units specified below
 
 
-applications
+rate
+Application rate in units specified below, or with units defined via the
+units package.
+
+
+applications
 Number of applications for selection of drift percentile
 
 
-water_depth
+water_depth
 Depth of the water body in cm
 
 
-drift_percentages
+drift_percentages
 Percentage drift values for which to calculate PECsw.
 Overrides 'drift_data' and 'distances' if not NULL.
 
 
-drift_data
+drift_data
 Source of drift percentage data. If 'JKI', the drift_data_JKI
 included in the package is used. If 'RF', the Rautmann drift data are calculated
 either in the original form or integrated over the width of the water body, depending
 on the 'formula' argument.
 
 
-crop_group_JKI
+crop_group_JKI
 When using the 'JKI' drift data, one of the German names
 as used in drift_parameters_focus.
 
 
-crop_group_focus
+crop_group_focus
 One of the crop groups as used in drift_parameters_focus
 
 
-distances
+distances
 The distances in m for which to get PEC values
 
 
-formula
+formula
 By default, the original Rautmann formula is used. If you
 specify "FOCUS", mean drift input over the width of the water body is
 calculated as described in Chapter 5.4.5 of the FOCUS surface water guidance
 
 
-water_width
+water_width
 Width of the water body in cm
 
 
-side_angle
+side_angle
 The angle of the side of the water relative to the bottom which
 is assumed to be horizontal, in degrees. The SYNOPS model assumes 45 degrees here.
 
 
-rate_units
-Defaults to g/ha
+rate_units
+Defaults to g/ha. For backwards compatibility, only used
+if the specified rate does not have units::units].
 
 
-PEC_units
+PEC_units
 Requested units for the calculated PEC. Only µg/L currently supported
 
 
     
     Value
-    
-
-The predicted concentration in surface water
+    The predicted concentration in surface water
+    
+    
+    Details
+    It is recommened to specify the arguments rate, water_depth and
+water_width using units::units from the units package.
     
     
     See also
@@ -153,16 +151,19 @@ is assumed to be horizontal, in degrees. The SYNOPS model assumes 45 degrees her
     
     Examples
     PEC_sw_drift(100)
+#> Units: [µg/L]
 #>        1 m        5 m       10 m       20 m 
 #> 0.92333333 0.19000000 0.09666667 0.05000000 
 # Alternatively, we can use the formula for a single application to
 # "Ackerbau" from the paper
 PEC_sw_drift(100, drift_data = "RF")
+#> Units: [µg/L]
 #>        1 m        5 m       10 m       20 m 
 #> 0.91976667 0.19064473 0.09680051 0.04915079 
 
 # This makes it possible to also use different distances
 PEC_sw_drift(100, distances = c(1, 3, 5, 6, 10, 20, 50, 100), drift_data = "RF")
+#> Units: [µg/L]
 #>        1 m        3 m        5 m        6 m       10 m       20 m       50 m 
 #> 0.91976667 0.31415827 0.19064473 0.15951494 0.09680051 0.04915079 0.02006434 
 #>      100 m 
@@ -171,6 +172,7 @@ is assumed to be horizontal, in degrees. The SYNOPS model assumes 45 degrees her
 # or consider aerial application
 PEC_sw_drift(100, distances = c(1, 3, 5, 6, 10, 20, 50, 100), drift_data = "RF", 
   crop_group_focus = "aerial")
+#> Units: [µg/L]
 #>        1 m        3 m        5 m        6 m       10 m       20 m       50 m 
 #> 16.8233333 11.0585820  9.0986174  8.4866460  6.9825178  4.7004640  1.8820816 
 #>      100 m 
@@ -178,6 +180,7 @@ is assumed to be horizontal, in degrees. The SYNOPS model assumes 45 degrees her
 
 # Using custom drift percentages is also supported
 PEC_sw_drift(100, drift_percentages = c(2.77, 0.95, 0.57, 0.48, 0.29, 0.15, 0.06, 0.03))
+#> Units: [µg/L]
 #>     2.77 %     0.95 %     0.57 %     0.48 %     0.29 %     0.15 %     0.06 % 
 #> 0.92333333 0.31666667 0.19000000 0.16000000 0.09666667 0.05000000 0.02000000 
 #>     0.03 % 
@@ -186,39 +189,44 @@ is assumed to be horizontal, in degrees. The SYNOPS model assumes 45 degrees her
 # The influence of assuming a 45° angle of the sides of the waterbody and the width of the 
 # waterbody can be illustrated
 PEC_sw_drift(100)
+#> Units: [µg/L]
 #>        1 m        5 m       10 m       20 m 
 #> 0.92333333 0.19000000 0.09666667 0.05000000 
 PEC_sw_drift(100, drift_data = "RF")
+#> Units: [µg/L]
 #>        1 m        5 m       10 m       20 m 
 #> 0.91976667 0.19064473 0.09680051 0.04915079 
 PEC_sw_drift(100, drift_data = "RF", formula = "FOCUS")
+#> Units: [µg/L]
 #>        1 m        5 m       10 m       20 m 
 #> 0.64246407 0.17414541 0.09235842 0.04798749 
 PEC_sw_drift(100, drift_data = "RF", formula = "FOCUS", side_angle = 45)
+#> Units: [µg/L]
 #>        1 m        5 m       10 m       20 m 
 #> 0.91780582 0.24877916 0.13194060 0.06855356 
 PEC_sw_drift(100, drift_data = "RF", formula = "FOCUS", side_angle = 45, water_width = 200)
+#> Units: [µg/L]
 #>        1 m        5 m       10 m       20 m 
-#> 0.30085000 0.09468652 0.05201349 0.02758547 
+#> 0.60169999 0.18937304 0.10402698 0.05517095 
 
     
-