| convertFlow {hydromad} | R Documentation |
This function converts between units of flow (volumetric throughput), designed mainly for hydrology applications. As a special case, this function can also convert units of volume or units of depth (length).
convertFlow(x, from = "mm", to = "mm", area.km2 = -1,
timestep.default = "days")
x |
a numeric vector or time series. |
from |
units to convert from (see Details). |
to |
units to convert into (see Details). |
area.km2 |
area (in square kilometres) that flow volume is averaged over. This must be given when converting between measures of depth and measures of volume. |
timestep.default |
the time step if not specified in
|
This function can convert flow rates between different volume units, or different timestep units, or both. Volume can be specified directly, or as a depth and area combination.
The unit specifications from and to can include a time
step, like "volume / timestep". A multiplier may also be
included with the time step, like "volume / N timesteps".
If no time step is specified in from and to, then it
is taken to be timestep.default.
The volume units supported are: (these can be abbreviated)
mL, cL, dL, L, daL, hL, kL, ML, GL, TL
cm^3, dm^3, m^3, km^3, ft^3
The depth units supported are: (these can be abbreviated)
mm, cm, metres, km, inches, feet
The time units supported are: (these can be abbreviated)
ms, seconds, minutes, hours, days, weeks, months, years / annum
Additionally, the value "cumecs" (cubic metres per second) is
equivalent to "m^3/sec".
the original object x, scaled.
The time step "year" refers to the average length of a year,
i.e. 365.25 days (one annum). Similarly,
the time step "month" refers to the average length of a month,
i.e. 365.25 / 12 = 30.4375 days.
Felix Andrews felix@nfrac.org
difftime
flowML <- c(0, 1, 100, 10) ## from megalitres per day to gigalitres per year convertFlow(flowML, from="ML / day", to="GL / yr") ## from ML/step to mm/step averaged over 50 km^2 convertFlow(flowML, from="ML", to="mm", area=50) ## from ML/day to cubic metres per second (flowCM <- convertFlow(flowML, from="ML/day", to="m^3/sec")) ## from cubic metres per second to mm/minute averaged over 0.1 km^2 convertFlow(flowCM, from="cumecs", to="mm/15min", area=0.1) ## 100 mm in inches convertFlow(100, to="in")