2.3 Roc right

R figure

Code

h <- 50
w <- 50 

grid.step <- 10

tpr1 <- 30
fpr1 <- 10
tpr2 <- 20
fpr2 <- 20
tpr3 <- 40
fpr3 <- 20

plot( c(0,w), c(0,h),  
     xaxs = "i",yaxs = "i",
     xaxt = 'n', yaxt = 'n',
     type = "n",
     xlab = "False positive rate", ylab = "True positive rate")


axis(2,c(0,tpr2,tpr1,tpr3,h),labels=c('0','tpr2','tpr1','tpr3','1'))
axis(1,c(0,fpr1,fpr2,w),labels=c('0','fpr1','fpr2-3','1'))

gx <- grid.step
while (gx <= w) {
  abline(v = gx, col="gray", lty="dotted")
  gx <- gx + grid.step
}
gy <- grid.step
while (gy <= h) {
  abline(h = gy, col="gray", lty="dotted")
  gy <- gy + grid.step
}

abline(c(tpr2,h/w),lty=2)

col1 <- "blue"
points( fpr1, tpr1, col=col1, type="o")
text( fpr1, tpr1, "C1", pos=3)
abline(h=tpr1, v=fpr1, col=col1, lty="dotted")

col2 <- "red"
points( fpr2, tpr2, col=col2, type="o")
text( fpr2, tpr2, "C2", pos=3)
abline(h=tpr2, v=fpr2, col=col2, lty="dotted")

col3 <- "green"
points( fpr3, tpr3, col=col3, type="o")
text( fpr3, tpr3, "C3", pos=3)
abline(h=tpr3, v=fpr3, col=col3, lty="dotted")

Python figure

Code

import matplotlib.pyplot as plt

h = 50
w = 50

grid_step = 10

tpr1 = 30
fpr1 = 10
tpr2 = 20
fpr2 = 20
tpr3 = 40
fpr3 = 20

fig, ax = plt.subplots()
ax.set_xlim(0, w)

(0.0, 50.0)

Code

ax.set_ylim(0, h)

(0.0, 50.0)

Code

ax.set_xlabel("False positive rate")
ax.set_ylabel("True positive rate")

ax.set_xticks([0, fpr1, fpr2, w])
ax.set_xticklabels([0, "fpr1", "fpr2-3", "1"])
ax.set_yticks([0, tpr2, tpr1, tpr3, h])
ax.set_yticklabels([0, "tpr2", "tpr1", "tpr3", "1"])

gx = grid_step
while gx <= w:
    ax.axvline(x=gx, color='gray', linestyle='dotted')
    gx += grid_step

gy = grid_step
while gy <= h:
    ax.axhline(y=gy, color='gray', linestyle='dotted')
    gy += grid_step

ax.axhline(y=tpr2, linestyle='dashed')

col1 = "blue"
ax.plot(fpr1, tpr1, marker='o', color=col1)
ax.text(fpr1, tpr1, "C1", verticalalignment='bottom', horizontalalignment='center')
ax.axhline(y=tpr1, color=col1, linestyle='dotted')
ax.axvline(x=fpr1, color=col1, linestyle='dotted')

col2 = "red"
ax.plot(fpr2, tpr2, marker='o', color=col2)
ax.text(fpr2, tpr2, "C2", verticalalignment='bottom', horizontalalignment='center')
ax.axhline(y=tpr2, color=col2, linestyle='dotted')
ax.axvline(x=fpr2, color=col2, linestyle='dotted')

col3 = "green"
ax.plot(fpr3, tpr3, marker='o', color=col3)
ax.text(fpr3, tpr3, "C3", verticalalignment='bottom', horizontalalignment='center')
ax.axhline(y=tpr3, color=col3, linestyle='dotted')
ax.axvline(x=fpr3, color=col3, linestyle='dotted')

plt.show()