In f0nzie/zFactor: Calculate the Compressibility Factor 'z' for Hydrocarbon Gases

# convert to tidy table for z values calculated by HY and read from SK chart
library(tidyr)
library(ggplot2)

# load both tables (matrices)
load(file = "../data/z_hy.rda")

z_sk_chart <- cbind(as.double(rownames(z_sk_chart)), z_sk_chart)  # new column for Tpr
rownames(z_sk_chart) <- NULL           # reset row names
colnames(z_sk_chart)[1] <- "Tpr"       # add column name
.z_chart <- as.data.frame(z_sk_chart)  # dataframe

z_hy_deriv <- cbind(as.double(rownames(z_hy_deriv)), z_hy_deriv)
rownames(z_hy_deriv) <- NULL
colnames(z_hy_deriv)[1] <- "Tpr"
.z_calcs <- as.data.frame(z_hy_deriv)


z_chart <- gather(.z_chart, "ppr", "z.chart", 2:8)
z_calcs <- gather(.z_calcs, "ppr", "z.calcs", 2:8)

zcombined <- cbind(z_chart, z.calc = z_calcs$z.calcs)
zcombined$dif <- zcombined$z.chart  - zcombined$z.calc

ggplot(zcombined, aes(x = ppr, y = z.chart, size = dif)) +
    geom_point(shape = 21)  +
    facet_grid(. ~Tpr)

z_HY <- zcombined
save(z_HY, file = "../data/z_HallYarborough.rda")

# in this case, th evariable name "ppr" has been changed to "Ppr"
ggplot(hy_dif, aes(x = Ppr, y = z.chart, size = dif)) +
    geom_point(shape = 21)  +
    facet_grid(. ~Tpr)