library(mosaicCalc)
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## Attaching package: 'mosaic'
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## Loading required package: mosaicCore
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## Attaching package: 'mosaicCore'
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## Attaching package: 'mosaicCalc'
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Graphical Optimization

Optimisasi grafis merujuk pada metode pencarian nilai maksimum atau minimum dari suatu fungsi dengan menggunakan visualisasi grafik. Dalam optimisasi grafis, pendekatan yang digunakan adalah dengan memplot fungsi tersebut pada suatu grafik dan mengidentifikasi lokasi di mana nilai maksimum atau minimum dari fungsi tersebut terjadi.

Sebagai contoh, kita akan mencari nilai maksimum dan minimum dari fungsi x 3 − 2 x 2 − 5 x + 6 

# Definisikan fungsi yang ingin dioptimalkan
fungsi <- function(x) {
  return(x^3 - 2*x^2 - 5*x + 6)  # Fungsi x^3 - 2x^2 - 5x + 6 sebagai contoh
}

# Mencari nilai minimum dan maksimum dari fungsi menggunakan optimize()
hasil_min <- optimize(fungsi, interval = c(-5, 5), maximum = FALSE)
hasil_max <- optimize(fungsi, interval = c(-5, 5), maximum = TRUE)

# Plot fungsi yang dioptimalkan
x <- seq(-5, 5, by = 0.1)
plot(x, fungsi(x), type = "l", main = "Grafik Fungsi dan Nilai Ekstremum", xlab = "Nilai x", ylab = "Nilai Fungsi")

# Menandai nilai minimum pada grafik
points(hasil_min$minimum, fungsi(hasil_min$minimum), col = "red", pch = 19)
text(hasil_min$minimum, fungsi(hasil_min$minimum) + 1, paste("Minimum =", round(hasil_min$objective, 2)), pos = 1, col = "red")

# Menandai nilai maksimum pada grafik
points(hasil_max$maximum, fungsi(hasil_max$maximum), col = "blue", pch = 19)
text(hasil_max$maximum, fungsi(hasil_max$maximum), paste("Maksimum =", round(hasil_max$objective, 2)), pos = 3, col = "blue")

Referensi: Kaplan, Daniel. 2022. MOSAIC Calculus. GitHub Pages. https://dtkaplan.github.io/MC2/