Plot monthly trend result from runPairs. The change in concentration
or flux is calculated from the `runPairs`

function. This plotting
function shows an arrow for each month. If the trend from year1 to year2
was increasing, the arrow is red and pointing up. If the trend was decreasing,
the arrow is black and pointing down.

## Usage

```
plotMonthTrend(pairResults, yMax = NA, arrowFactor = 0.75, flux = TRUE,
printTitle = TRUE, concLab = 1, monthLab = 1)
```

## Arguments

- pairResults
results from

`runPairs`

.- yMax
numeric. Upper limit for plot. Default is

`NA`

, which will use the maximum of the data.- arrowFactor
numeric. Scaling factor for the size of the arrows. The arrows are automatically scaled to the overall trend. This scaling factor helps adjust how big/small they are.

- flux
logical.

`TRUE`

is flux,`FALSE`

is concentration. Default is`TRUE`

.- printTitle
logical variable if TRUE title is printed, if FALSE title is not printed (this is best for a multi-plot figure)

- concLab
object of concUnit class, or numeric represented the short code, or character representing the descriptive name. By default, this argument sets concentration labels to use either Concentration or Conc (for tiny plots). Units are taken from the eList$INFO$param.units. To use any other words than "Concentration" see

`vignette(topic = "units", package = "EGRET")`

.- monthLab
object of monthLabel class, or numeric represented the short code, or character representing the descriptive name.

## Details

The flux values for each month are flow normalized monthly watershed yields expressed as kg/month/km^2. The concentrations are the mean flow normalized concentration, expressed in whatever concentration units the raw data are expressed as (typically mg/L).

## Examples

```
eList <- Choptank_eList
year1 <- 1985
year2 <- 2010
# \donttest{
pairOut_1 <- runPairs(eList, year1, year2, windowSide = 0)
#> Sample1 has 606 Samples and 605 are uncensored
#> Sample2 has 606 Samples and 605 are uncensored
#> minNumObs has been set to 100 minNumUncen has been set to 50
#> Sample1 has 606 Samples and 605 are uncensored
#> Sample2 has 606 Samples and 605 are uncensored
#> minNumObs has been set to 100 minNumUncen has been set to 50
#>
#> Choptank River
#> Inorganic nitrogen (nitrate and nitrite)
#> Water Year
#>
#> Change estimates 2010 minus 1985
#>
#> For concentration: total change is 0.429 mg/L
#> expressed as Percent Change is +42.27 %
#>
#> Concentration v. Q Trend Component +42.27 %
#> Q Trend Component 0 %
#>
#>
#> For flux: total change is 0.0342 million kg/year
#> expressed as Percent Change is +29.44 %
#>
#> Concentration v. Q Trend Component +29.44 %
#> Q Trend Component 0 %
#>
#> TotalChange CQTC QTC x10 x11 x20 x22
#> Conc 0.429 0.429 0 1.01 1.01 1.44 1.44
#> Flux 0.034 0.034 0 0.12 0.12 0.15 0.15
plotMonthTrend(pairOut_1)
plotMonthTrend(pairOut_1, flux = FALSE)
eList <- setPA(eList, paStart = 12, paLong = 3)
pairOut_2 <- runPairs(eList, year1, year2, windowSide = 0)
#> Sample1 has 606 Samples and 605 are uncensored
#> Sample2 has 606 Samples and 605 are uncensored
#> minNumObs has been set to 100 minNumUncen has been set to 50
#> Sample1 has 606 Samples and 605 are uncensored
#> Sample2 has 606 Samples and 605 are uncensored
#> minNumObs has been set to 100 minNumUncen has been set to 50
#>
#> Choptank River
#> Inorganic nitrogen (nitrate and nitrite)
#> Season Consisting of Dec Jan Feb
#>
#> Change estimates 2010 minus 1985
#>
#> For concentration: total change is 0.369 mg/L
#> expressed as Percent Change is +30.50 %
#>
#> Concentration v. Q Trend Component +30.50 %
#> Q Trend Component 0 %
#>
#>
#> For flux: total change is 0.0403 million kg/year
#> expressed as Percent Change is +22.68 %
#>
#> Concentration v. Q Trend Component +22.68 %
#> Q Trend Component 0 %
#>
#> TotalChange CQTC QTC x10 x11 x20 x22
#> Conc 0.37 0.37 0 1.21 1.21 1.58 1.58
#> Flux 0.04 0.04 0 0.18 0.18 0.22 0.22
plotMonthTrend(pairOut_2)
eList <- setPA(eList, paStart = 1, paLong = 12)
pairOut_3 <- runPairs(eList, year1, year2, windowSide = 0)
#> Sample1 has 606 Samples and 605 are uncensored
#> Sample2 has 606 Samples and 605 are uncensored
#> minNumObs has been set to 100 minNumUncen has been set to 50
#> Sample1 has 606 Samples and 605 are uncensored
#> Sample2 has 606 Samples and 605 are uncensored
#> minNumObs has been set to 100 minNumUncen has been set to 50
#>
#> Choptank River
#> Inorganic nitrogen (nitrate and nitrite)
#> Calendar Year
#>
#> Change estimates 2010 minus 1985
#>
#> For concentration: total change is 0.433 mg/L
#> expressed as Percent Change is +42.46 %
#>
#> Concentration v. Q Trend Component +42.46 %
#> Q Trend Component 0 %
#>
#>
#> For flux: total change is 0.034 million kg/year
#> expressed as Percent Change is +29.09 %
#>
#> Concentration v. Q Trend Component +29.09 %
#> Q Trend Component 0 %
#>
#> TotalChange CQTC QTC x10 x11 x20 x22
#> Conc 0.433 0.433 0 1.02 1.02 1.45 1.45
#> Flux 0.034 0.034 0 0.12 0.12 0.15 0.15
plotMonthTrend(pairOut_3)
# }
```