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These tables describe trends in flow-normalized concentration and in flow-normalized flux. They are described as changes in real units or in percent and as slopes in real units per year or in percent per year. They are computed over pairs of time points. These time points can be user-defined or they can be set by the program to be the final year of the record and a set of years that are multiples of 5 years prior to that. tableChangeSingle is a version of the same code that will produce output only for flow-normalized concentration or flow-normalized flux, but not both

Usage

tableChange(eList, fluxUnit = 9, yearPoints = NA)

tableChangeSingle(eList, fluxUnit = 9, yearPoints = NA, flux = FALSE)

Arguments

eList

named list with at least the Daily and INFO dataframes

fluxUnit

object of fluxUnit class. printFluxUnitCheatSheet, or numeric represented the short code, or character representing the descriptive name.

yearPoints

numeric vector listing the years for which the change or slope computations are made, they need to be in chronological order. For example yearPoints=c(1975,1985,1995,2005), default is NA (which allows the program to set yearPoints automatically)

flux

logical if TRUE results are returned in flux, if FALSE concentration. Default is set to FALSE.

Value

dataframe with Year1, Year2, change[mg/L], slope[mg/L], change[percent], slope[percent] columns. The data in each row is the change or slope calculated from Year1 to Year2

Examples

eList <- Choptank_eList
# Water Year:
# \donttest{
tableChange(eList, fluxUnit = 8, yearPoints = c(1980, 1995, 2011))
#> 
#>    Choptank River 
#>    Inorganic nitrogen (nitrate and nitrite)
#>    Water Year 
#> 
#>            Concentration trends
#>    time span       change     slope    change     slope
#>                      mg/L   mg/L/yr        %       %/yr
#> 
#>  1980  to  1995       0.2     0.013        20       1.3
#>  1980  to  2011      0.45     0.015        45       1.5
#>  1995  to  2011      0.26     0.016        21       1.3
#> 
#> 
#>                  Flux Trends
#>    time span          change        slope       change        slope
#>                   10^3 kg/yr    10^3 kg/yr /yr      %         %/yr
#>  1980  to  1995           27          1.8           26          1.7
#>  1980  to  2011           42          1.4           39          1.3
#>  1995  to  2011           15         0.92           11         0.69
tableChange(eList, fluxUnit = 5) 
#> 
#>    Choptank River 
#>    Inorganic nitrogen (nitrate and nitrite)
#>    Water Year 
#> 
#>            Concentration trends
#>    time span       change     slope    change     slope
#>                      mg/L   mg/L/yr        %       %/yr
#> 
#>  1981  to  1986     0.039    0.0079       3.9      0.79
#>  1981  to  1991      0.14     0.014        14       1.4
#>  1981  to  1996      0.21     0.014        21       1.4
#>  1981  to  2001      0.27     0.013        27       1.3
#>  1981  to  2006      0.36     0.015        36       1.5
#>  1981  to  2011      0.46     0.015        46       1.5
#>  1986  to  1991       0.1     0.021        10         2
#>  1986  to  1996      0.18     0.018        17       1.7
#>  1986  to  2001      0.23     0.015        22       1.5
#>  1986  to  2006      0.32     0.016        31       1.6
#>  1986  to  2011      0.42     0.017        40       1.6
#>  1991  to  1996      0.07     0.014       6.2       1.2
#>  1991  to  2001      0.13     0.013        11       1.1
#>  1991  to  2006      0.22     0.015        19       1.3
#>  1991  to  2011      0.31     0.016        27       1.4
#>  1996  to  2001     0.055     0.011       4.5      0.91
#>  1996  to  2006      0.15     0.015        12       1.2
#>  1996  to  2011      0.24     0.016        20       1.3
#>  2001  to  2006     0.094     0.019       7.4       1.5
#>  2001  to  2011      0.19     0.019        15       1.5
#>  2006  to  2011     0.095     0.019         7       1.4
#> 
#> 
#>                  Flux Trends
#>    time span          change        slope       change        slope
#>                   tons/yr      tons/yr   /yr      %         %/yr
#>  1981  to  1986           12          2.4           10            2
#>  1981  to  1991           24          2.4           20            2
#>  1981  to  1996           29          1.9           24          1.6
#>  1981  to  2001           35          1.8           29          1.5
#>  1981  to  2006           43          1.7           36          1.4
#>  1981  to  2011           44          1.5           37          1.2
#>  1986  to  1991           12          2.5          9.4          1.9
#>  1986  to  1996           17          1.7           13          1.3
#>  1986  to  2001           23          1.5           18          1.2
#>  1986  to  2006           31          1.5           23          1.2
#>  1986  to  2011           32          1.3           24         0.97
#>  1991  to  1996          4.7         0.94          3.3         0.65
#>  1991  to  2001           11          1.1          7.5         0.75
#>  1991  to  2006           19          1.2           13         0.86
#>  1991  to  2011           20         0.98           14         0.68
#>  1996  to  2001          6.1          1.2          4.1         0.82
#>  1996  to  2006           14          1.4          9.4         0.94
#>  1996  to  2011           15            1           10         0.67
#>  2001  to  2006          7.9          1.6          5.1            1
#>  2001  to  2011          8.9         0.89          5.8         0.58
#>  2006  to  2011          1.1         0.21         0.65         0.13
# Winter:
eList <- setPA(eList, paStart = 12, paLong = 3)
tableChange(eList, fluxUnit = 8, yearPoints = c(1980, 1995, 2011))
#> 
#>    Choptank River 
#>    Inorganic nitrogen (nitrate and nitrite)
#>    Season Consisting of Dec Jan Feb 
#> 
#>            Concentration trends
#>    time span       change     slope    change     slope
#>                      mg/L   mg/L/yr        %       %/yr
#> 
#>  1980  to  1995       0.2     0.013        18       1.2
#>  1980  to  2011      0.46     0.015        42       1.3
#>  1995  to  2011      0.26     0.016        20       1.3
#> 
#> 
#>                  Flux Trends
#>    time span          change        slope       change        slope
#>                   10^3 kg/yr    10^3 kg/yr /yr      %         %/yr
#>  1980  to  1995           37          2.5           24          1.6
#>  1980  to  2011           59          1.9           38          1.2
#>  1995  to  2011           22          1.4           12         0.72

# Water Year:
eList <- setPA(eList, paStart = 10, paLong = 12)
#This returns concentration ASCII table in the console:
tableChangeSingle(eList, fluxUnit = 8, yearPoints = c(1980, 1995, 2011), flux = FALSE)
#> 
#>    Choptank River 
#>    Inorganic nitrogen (nitrate and nitrite)
#>    Water Year 
#> 
#>            Concentration trends
#>    time span       change     slope    change     slope
#>                      mg/L   mg/L/yr        %       %/yr
#> 
#>  1980  to  1995       0.2     0.013        20       1.3
#>  1980  to  2011      0.45     0.015        45       1.5
#>  1995  to  2011      0.26     0.016        21       1.3
#Returns a data frame:
change <- tableChangeSingle(eList, fluxUnit = 8, yearPoints=c(1980, 1995, 2011), flux = FALSE) 
#> 
#>    Choptank River 
#>    Inorganic nitrogen (nitrate and nitrite)
#>    Water Year 
#> 
#>            Concentration trends
#>    time span       change     slope    change     slope
#>                      mg/L   mg/L/yr        %       %/yr
#> 
#>  1980  to  1995       0.2     0.013        20       1.3
#>  1980  to  2011      0.45     0.015        45       1.5
#>  1995  to  2011      0.26     0.016        21       1.3
#This returns flux values as a data frame:
df <- tableChangeSingle(eList, fluxUnit = 8, yearPoints=c(1980, 1995, 2011), flux = TRUE)  
#> 
#>    Choptank River 
#>    Inorganic nitrogen (nitrate and nitrite)
#>    Water Year 
#> 
#> 
#> 
#>                  Flux Trends
#>    time span          change        slope       change        slope
#>                  10^3 kg/yr   10^3 kg/yr/yr      %         %/yr
#> 
#>  1980  to  1995           27          1.8           26          1.7
#>  1980  to  2011           42          1.4           39          1.3
#>  1995  to  2011           15         0.92           11         0.69
# Winter Concentration only:
eList <- setPA(eList, paStart = 12, paLong = 3)
df.winter <- tableChangeSingle(eList, fluxUnit = 8, yearPoints=c(1980, 1995, 2011), flux = FALSE)
#> 
#>    Choptank River 
#>    Inorganic nitrogen (nitrate and nitrite)
#>    Season Consisting of Dec Jan Feb 
#> 
#>            Concentration trends
#>    time span       change     slope    change     slope
#>                      mg/L   mg/L/yr        %       %/yr
#> 
#>  1980  to  1995       0.2     0.013        18       1.2
#>  1980  to  2011      0.46     0.015        42       1.3
#>  1995  to  2011      0.26     0.016        20       1.3

# }