1 Configuración y Carga de Datos

##### UNIVERSIDAD CENTRAL DEL ECUADOR #####
#### AUTOR: MARTIN SARMIENTO ####
### CARRERA: INGENIERÍA EN PETRÓLEOS #####


#### VARIABLE GHI ####
## DATASET ##
setwd("~/R/GHI")
# Cargar dataset
Datos <- read.csv("DataSet_Mundial_Final.csv", sep = ";", dec = ",", fileEncoding = "latin1")
# Estructura de los datos
str(Datos)
## 'data.frame':    58978 obs. of  29 variables:
##  $ ï..OBJECTID           : int  2 3 4 5 6 7 8 9 10 11 ...
##  $ code                  : chr  "00001-AFG-P" "00002-AFG-P" "00003-AFG-P" "00004-AFG-P" ...
##  $ plant_name            : chr  "Badghis Solar Power Plant" "Balkh solar farm" "Behsood solar farm" "Dab Pal 4 solar farm" ...
##  $ country               : chr  "Afghanistan" "Afghanistan" "Afghanistan" "Afghanistan" ...
##  $ operational_status    : chr  "cancelled - inferred 4 y" "cancelled - inferred 4 y" "cancelled - inferred 4 y" "shelved - inferred 2 y" ...
##  $ longitude             : num  62.9 67.1 70.4 66.2 65.7 ...
##  $ latitude              : num  35.1 36.7 34.4 33.8 31.7 ...
##  $ elevation             : int  918 359 629 2288 1060 1060 1392 398 410 1012 ...
##  $ area                  : num  6.74 10.72 487.73 111.8 1929.96 ...
##  $ size                  : chr  "Small" "Small" "Small" "Small" ...
##  $ slope                 : num  7.38 0.49 1.1 6.16 1.23 ...
##  $ slope_type            : chr  "Moderado" "Plano o casi plano" "Plano o casi plano" "Moderado" ...
##  $ curvature             : num  -0.024 0 0 0.045 -0.005 -0.005 -0.015 0 0 -0.009 ...
##  $ curvature_type        : chr  "Superficies cóncavas / Valles" "Superficies planas o intermedias" "Superficies planas o intermedias" "Superficies convexas / Crestas" ...
##  $ aspect                : num  96.8 358.5 36.2 305.8 248.4 ...
##  $ aspect_type           : chr  "East" "North" "Northeast" "Northwest" ...
##  $ dist_to_road          : num  7037.1 92.7 112.1 1705.3 115.8 ...
##  $ ambient_temperature   : num  14.4 17.88 21.32 8.86 19.64 ...
##  $ ghi                   : num  5.82 5.58 5.8 6.75 6.62 ...
##  $ humidity              : num  47.7 42.3 36.4 37.3 24.2 ...
##  $ wind_speed            : num  0.039 0.954 0.234 0.943 0.37 ...
##  $ wind_direction        : num  187.5 207.4 255.6 160.3 97.7 ...
##  $ dt_wind               : chr  "South" "Southwest" "West" "South" ...
##  $ solar_aptitude        : num  0.72 0.635 0.685 0.659 0.819 0.819 0.818 0.642 0.63 0.374 ...
##  $ solar_aptitude_rounded: int  7 6 7 7 8 8 8 6 6 4 ...
##  $ solar_aptittude_class : chr  "Alta" "Alta" "Alta" "Alta" ...
##  $ capacity              : num  32 40 60 3000 100 100 36 50 25 100 ...
##  $ optimal_tilt          : num  30 31 31.1 33 31 ...
##  $ pv_potential          : num  4.61 4.41 4.57 5.42 5.17 ...
# Cargamos las librerias
library(dplyr)
## 
## Adjuntando el paquete: 'dplyr'
## The following objects are masked from 'package:stats':
## 
##     filter, lag
## The following objects are masked from 'package:base':
## 
##     intersect, setdiff, setequal, union
library(gt)
library(e1071)

2 Cálculo de Intervalos y Frecuencias

# Extraer variable
Variable <- na.omit(Datos$ghi)
N <- length(Variable)

# CÁLCULO LÍMITES DECIMALES
min_dec <- min(Variable)
max_dec <- max(Variable)
k_dec <- floor(1 + 3.322 * log10(N))
rango_dec <- max(Variable) - min(Variable)
amplitud_dec <- rango_dec / k_dec

# Cortes exactos
cortes_dec <- seq(min(Variable), max(Variable), length.out = k_dec + 1)
cortes_dec[length(cortes_dec)] <- max(Variable) + 0.0001

# Frecuencias
inter_dec <- cut(Variable, breaks = cortes_dec, include.lowest = TRUE, right = FALSE)
ni_dec <- as.vector(table(inter_dec))

# CÁLCULOS MATEMÁTICOS 
hi_dec <- (ni_dec / N) * 100
Ni_asc_dec <- cumsum(ni_dec)
Hi_asc_dec <- cumsum(hi_dec)
Ni_desc_dec <- rev(cumsum(rev(ni_dec)))
Hi_desc_dec <- rev(cumsum(rev(hi_dec)))

# Dataframe Decimal
TDF_Decimal <- data.frame(
  Li = cortes_dec[1:k_dec],
  Ls = cortes_dec[2:(k_dec+1)],
  MC = (cortes_dec[1:k_dec] + cortes_dec[2:(k_dec+1)]) / 2,
  ni = ni_dec,
  hi = hi_dec,
  Ni_asc = Ni_asc_dec,
  Ni_desc = Ni_desc_dec,
  Hi_asc = Hi_asc_dec,
  Hi_desc = Hi_desc_dec)


# CÁLCULO LÍMITES ENTEROS (CORREGIDO PARA GHI)
BASE <- 1
min_int <- floor(min(Variable) / BASE) * BASE
max_int <- ceiling(max(Variable) / BASE) * BASE
k_int_sug <- floor(1 + 3.322 * log10(N))
Rango_int <- max_int - min_int

# Calculamos amplitud entera
Amplitud_int <- ceiling(Rango_int / k_int_sug) 
if(Amplitud_int == 0) Amplitud_int <- 1

# Generamos la secuencia de cortes
cortes_int <- seq(from = min_int, by = Amplitud_int, length.out = k_int_sug + 1)
if(max(cortes_int) < max(Variable)) {
  cortes_int <- c(cortes_int, max(cortes_int) + Amplitud_int)
}

while(length(cortes_int) > 2 && cortes_int[length(cortes_int)-1] >= max(Variable)) {
  cortes_int <- cortes_int[-length(cortes_int)]
}

# Definimos los límites
K_real <- length(cortes_int) - 1
lim_inf_int <- cortes_int[1:K_real]
lim_sup_int <- cortes_int[2:(K_real+1)]

# Frecuencias 
inter_int <- cut(Variable, breaks = cortes_int, include.lowest = TRUE, right = FALSE)
ni_int <- as.vector(table(inter_int))

# CÁLCULOS MATEMÁTICOS
hi_int <- (ni_int / N) * 100
Ni_asc_int <- cumsum(ni_int)
Hi_asc_int <- cumsum(hi_int)
Ni_desc_int <- rev(cumsum(rev(ni_int)))
Hi_desc_int <- rev(cumsum(rev(hi_int)))

# Dataframe Entero
TDF_Enteros <- data.frame(
  Li = lim_inf_int,
  Ls = lim_sup_int,
  MC = (lim_inf_int + lim_sup_int) / 2,
  ni = ni_int,
  hi = hi_int,
  Ni_asc = Ni_asc_int,
  Ni_desc = Ni_desc_int,
  Hi_asc = Hi_asc_int,
  Hi_desc = Hi_desc_int)

3 Tabla de Distribución de Frecuencias

3.1 Tabla con Límites Decimales

# Crear Dataframe
TDF_Dec_Final <- data.frame(
  Li      = as.character(round(TDF_Decimal$Li, 2)),
  Ls      = as.character(round(TDF_Decimal$Ls, 2)),
  MC      = as.character(round(TDF_Decimal$MC, 2)),
  ni      = as.character(TDF_Decimal$ni),
  hi      = as.character(round(TDF_Decimal$hi, 2)),
  Ni_asc  = as.character(TDF_Decimal$Ni_asc),
  Ni_desc = as.character(TDF_Decimal$Ni_desc),
  Hi_asc  = as.character(round(TDF_Decimal$Hi_asc, 2)),
  Hi_desc = as.character(round(TDF_Decimal$Hi_desc, 2))
)

# Calcular Totales
totales_dec <- c("TOTAL", "-", "-", sum(TDF_Decimal$ni), round(sum(TDF_Decimal$hi), 2), "-", "-", "-", "-")
TDF_Dec_Final <- rbind(TDF_Dec_Final, totales_dec)

# Generar GT
TDF_Dec_Final %>%
  gt() %>%
  tab_header(title = md("**Tabla N°1 de Distribución de Frecuencias de GHI (kWh/m²) de las Plantas Solares**")) %>%
  cols_label(
    Li = "Lim. Inf", 
    Ls = "Lim. Sup", 
    MC = "Marca Clase",
    ni = "Frec. Abs (ni)", 
    hi = "Frec. Rel (%)",
    Ni_asc = "Ni (Asc)", 
    Ni_desc = "Ni (Desc)",
    Hi_asc = "Hi Asc (%)", 
    Hi_desc = "Hi Desc (%)"
  ) %>%
  cols_align(align = "center", columns = everything()) %>%
  tab_options(heading.title.font.size = px(14), column_labels.background.color = "#F0F0F0")
Tabla N°1 de Distribución de Frecuencias de GHI (kWh/m²) de las Plantas Solares
Lim. Inf Lim. Sup Marca Clase Frec. Abs (ni) Frec. Rel (%) Ni (Asc) Ni (Desc) Hi Asc (%) Hi Desc (%)
0 0.5 0.25 3 0.01 3 58978 0.01 100
0.5 1.01 0.75 0 0 3 58975 0.01 99.99
1.01 1.51 1.26 0 0 3 58975 0.01 99.99
1.51 2.01 1.76 0 0 3 58975 0.01 99.99
2.01 2.52 2.26 0 0 3 58975 0.01 99.99
2.52 3.02 2.77 219 0.37 222 58975 0.38 99.99
3.02 3.52 3.27 6150 10.43 6372 58756 10.8 99.62
3.52 4.02 3.77 13445 22.8 19817 52606 33.6 89.2
4.02 4.53 4.28 11774 19.96 31591 39161 53.56 66.4
4.53 5.03 4.78 9885 16.76 41476 27387 70.32 46.44
5.03 5.53 5.28 7675 13.01 49151 17502 83.34 29.68
5.53 6.04 5.78 7134 12.1 56285 9827 95.43 16.66
6.04 6.54 6.29 1938 3.29 58223 2693 98.72 4.57
6.54 7.04 6.79 523 0.89 58746 755 99.61 1.28
7.04 7.54 7.29 165 0.28 58911 232 99.89 0.39
7.54 8.05 7.8 67 0.11 58978 67 100 0.11
TOTAL - - 58978 100 - - - -

3.2 Tabla con Límites Enteros

# Crear Dataframe
TDF_Int_Final <- data.frame(
  Li      = as.character(TDF_Enteros$Li),
  Ls      = as.character(TDF_Enteros$Ls),
  MC      = as.character(TDF_Enteros$MC),
  ni      = as.character(TDF_Enteros$ni),
  hi      = as.character(round(TDF_Enteros$hi, 2)),
  Ni_asc  = as.character(TDF_Enteros$Ni_asc),
  Ni_desc = as.character(TDF_Enteros$Ni_desc),
  Hi_asc  = as.character(round(TDF_Enteros$Hi_asc, 2)),
  Hi_desc = as.character(round(TDF_Enteros$Hi_desc, 2))
)

# Calcular Totales
totales_int <- c("TOTAL", "-", "-", sum(TDF_Enteros$ni), round(sum(TDF_Enteros$hi), 2), "-", "-", "-", "-")
TDF_Int_Final <- rbind(TDF_Int_Final, totales_int)

# Generar GT
TDF_Int_Final %>%
  gt() %>%
  tab_header(title = md("**Tabla N°2 de Distribución de Frecuencias de GHI (kWh/m²) de las Plantas Solares**")) %>%
  cols_label(
    Li = "Lim. Inf", 
    Ls = "Lim. Sup", 
    MC = "Marca Clase",
    ni = "Frec. Abs (ni)", 
    hi = "Frec. Rel (%)",
    Ni_asc = "Ni (Asc)", 
    Ni_desc = "Ni (Desc)",
    Hi_asc = "Hi Asc (%)", 
    Hi_desc = "Hi Desc (%)"
  ) %>%
  cols_align(align = "center", columns = everything()) %>%
  tab_options(heading.title.font.size = px(14), column_labels.background.color = "#F0F0F0")
Tabla N°2 de Distribución de Frecuencias de GHI (kWh/m²) de las Plantas Solares
Lim. Inf Lim. Sup Marca Clase Frec. Abs (ni) Frec. Rel (%) Ni (Asc) Ni (Desc) Hi Asc (%) Hi Desc (%)
0 1 0.5 3 0.01 3 58978 0.01 100
1 2 1.5 0 0 3 58975 0.01 99.99
2 3 2.5 199 0.34 202 58975 0.34 99.99
3 4 3.5 19150 32.47 19352 58776 32.81 99.66
4 5 4.5 21739 36.86 41091 39626 69.67 67.19
5 6 5.5 14813 25.12 55904 17887 94.79 30.33
6 7 6.5 2803 4.75 58707 3074 99.54 5.21
7 8 7.5 264 0.45 58971 271 99.99 0.46
8 9 8.5 7 0.01 58978 7 100 0.01
TOTAL - - 58978 100 - - - -

4 Análisis Gráfico

4.1 Histogramas de Cantidad

par(mar = c(8, 7, 5, 2)) 
barplot(TDF_Enteros$ni, 
        names.arg = TDF_Enteros$MC,
        main = "",
        xlab = "", 
        ylab = "",
        col = "#EEC900",
        ylim = c(0, max(TDF_Enteros$ni) * 1.2),
        space = 0, 
        las = 2, 
        cex.names = 0.7)
mtext("Cantidad", side = 2, line = 4.5, cex = 1, font = 1)
mtext("GHI (kWh/m²)", side = 1, line = 4)

mtext("Gráfica N°1: Distribución de Cantidad de Plantas Solares por GHI", 
      side = 3, 
      line = 2, 
      adj = 0.5, 
      cex = 0.9, 
      font = 2)

par(mar = c(8, 7, 5, 2))
barplot(TDF_Enteros$ni, 
        main="",
        xlab = "",
        ylab = "",
        names.arg = TDF_Enteros$MC,
        col = "#EEC900",
        space = 0,
        cex.names = 0.7,
        las = 2,
        ylim = c(0, 58978)) 
mtext("Cantidad", side = 2, line = 4.5, cex = 1, font = 1)
mtext("GHI (kWh/m²)", side = 1, line = 4)

mtext("Gráfica N°2: Distribución de Cantidad de Plantas Solares por GHI", 
      side = 3, 
      line = 2, 
      adj = 0.5, 
      cex = 0.9, 
      font = 2)

4.2 Histogramas Porcentuales

par(mar = c(8, 5, 5, 2))
bp3 <- barplot(TDF_Enteros$hi, 
        main = "",
        xlab = "",
        ylab = "Porcentaje (%)",
        col = "#EEC900",
        space = 0,
        names.arg = TDF_Enteros$MC,
        cex.names = 0.7,
        las = 2,
        ylim = c(0, max(TDF_Enteros$hi) * 1.2))
mtext("GHI (kWh/m²)", side = 1, line = 4)

mtext("Gráfica N°3: Distribución Porcentual de las Plantas Solares por GHI", 
      side = 3, 
      line = 2, 
      adj = 0.5, 
      cex = 0.9, 
      font = 2)

text(x = bp3, 
     y = TDF_Enteros$hi, 
     labels = paste0(round(TDF_Enteros$hi, 2), "%"), 
     pos = 3, cex = 0.6, col = "black")

par(mar = c(8, 5, 5, 2))
bp4 <- barplot(TDF_Enteros$hi, 
        main = "",
        xlab = "",
        ylab = "Porcentaje (%)",
        col = "#EEC900",
        space = 0,
        names.arg = TDF_Enteros$MC,
        las = 2,
        cex.names = 0.7,
        ylim = c(0, 100)) 
mtext("GHI (kWh/m²)", side = 1, line = 4)

mtext("Gráfica N°4: Distribución Porcentual de las Plantas Solares por GHI", 
      side = 3, 
      line = 2, 
      adj = 0.5, 
      cex = 0.9, 
      font = 2)

text(x = bp4, 
     y = TDF_Enteros$hi, 
     labels = paste0(round(TDF_Enteros$hi, 2), "%"), 
     pos = 3, cex = 0.6, col = "black")

4.3 Diagrama de Cajas (Boxplot)

par(mar = c(5, 5, 4, 2))
boxplot(Variable, 
        horizontal = TRUE,
        col = "#EEC900",
        xlab = "GHI (kWh/m²)",
        cex.main = 0.9,
        main = "Gráfica N°5: Distribución de GHI en las Plantas Solares")

4.4 Ojivas

par(mar = c(5, 5, 7, 10), xpd = TRUE)

# Coordenadas
x_asc <- TDF_Enteros$Ls
x_desc <- TDF_Enteros$Li
y_asc <- TDF_Enteros$Ni_asc
y_desc <- TDF_Enteros$Ni_desc

# 1. Dibujar la Ascendente 
plot(x_asc, y_asc,
     type = "b", 
     main = "",
     xlab = "GHI (kWh/m²)",
     ylab = "Frecuencia acumulada",
     col = "black",
     pch = 19, 
     xlim = c(min(TDF_Enteros$Li), max(x_asc)), 
     ylim = c(0, sum(TDF_Enteros$ni)),
     bty = "l"
)

# 2. Agregar la Descendente 
lines(x_desc, y_desc, col = "#CD8500", type = "b", pch = 19)

grid()
mtext("Gráfica N°6: Ojivas Ascendentes y Descendentes de la\nDistribución de GHI en las Plantas Solares", 
      side = 3, 
      line = 3, 
      adj = 0.5, 
      cex = 0.9, 
      font = 2)

legend("left", 
       legend = c("Ascendente", "Descendente"), 
       col = c("black", "#CD8500"), 
       lty = 1, 
       pch = 1, 
       cex = 0.6, 
       inset = c(0.05, 0.05),
       bty = "n")

5 Indicadores Estadísticos

## INDICADORES DE TENDENCIA CENTRAL
# Media aritmética
media <- round(mean(Variable), 2)

# Mediana
mediana <- round(median(Variable), 2)

# Moda
max_frecuencia <- max(TDF_Enteros$ni)
moda_vals <- TDF_Enteros$MC[TDF_Enteros$ni == max_frecuencia]
moda_txt <- paste(round(moda_vals, 2), collapse = ", ")

## INDICADORES DE DISPERSIÓN
# Varianza
varianza <- var(Variable)

# Desviación Estándar
sd_val <- sd(Variable)

# Coeficiente de Variación
cv <- round((sd_val / abs(media)) * 100, 2)

## INDICADORES DE FORMA
# Coeficiente de Asimetría
asimetria <- skewness(Variable, type = 2)

# Curtosis
curtosis <- kurtosis(Variable)

# Outliers
Q1 <- quantile(Variable, 0.25)
Q3 <- quantile(Variable, 0.75)
IQR_val <- Q3 - Q1
lim_inf <- Q1 - 1.5 * IQR_val
lim_sup <- Q3 + 1.5 * IQR_val

outliers_data <- Variable[Variable < lim_inf | Variable > lim_sup]
num_outliers <- length(outliers_data)

if(num_outliers > 0){
  rango_outliers <- paste0(num_outliers, " [", round(min(outliers_data), 2), "; ", round(max(outliers_data), 2), "]")
} else {
  rango_outliers <- "0 [Sin Outliers]"
}

tabla_indicadores <- data.frame(
 "Variable" = c("GHI (kWh/m²)"),
 "Rango_MinMax" = paste0("[", round(min(Variable), 2), "; ", round(max(Variable), 2), "]"),
 "X" = c(media),
 "Me" = c(mediana),
 "Mo" = c(moda_txt),
 "V" = c(varianza),
 "Sd" = c(sd_val),
 "Cv" = c(cv),
 "As" = c(asimetria),
 "K" = c(curtosis),
 "Outliers" = rango_outliers)

# Generar Tabla GT
tabla_conclusiones_gt <- tabla_indicadores %>%
 gt() %>%
 tab_header(title = md("**Tabla N°3 de Conclusiones de GHI de las Plantas Solares**")) %>%
 tab_source_note(source_note = "Autor: Martin Sarmiento") %>%
 cols_label(
  Variable = "Variable",
  Rango_MinMax = "Rango",
  X = "Media (X)",
  Me = "Mediana (Me)",
  Mo = "Moda (Mo)",
  V = "Varianza (V)",
  Sd = "Desv. Est. (Sd)",
  Cv = "C.V. (%)",
  As = "Asimetría (As)",
  K = "Curtosis (K)",
  Outliers = "Outliers [Intervalo]"
 ) %>%
 tab_options(
  heading.title.font.size = px(16),
  column_labels.background.color = "#F0F0F0"
 )

tabla_conclusiones_gt
Tabla N°3 de Conclusiones de GHI de las Plantas Solares
Variable Rango Media (X) Mediana (Me) Moda (Mo) Varianza (V) Desv. Est. (Sd) C.V. (%) Asimetría (As) Curtosis (K) Outliers [Intervalo]
GHI (kWh/m²) [0; 8.05] 4.55 4.47 4.5 0.737728 0.8589109 18.88 0.4615969 -0.408403 112 [0; 8.05]
Autor: Martin Sarmiento

6 Conclusiones

La variable “GHI” fluctúa entre 0 y 8.05 kWh/m² y sus valores se encuentran alrededor de 4.47 kWh/m², con una desviación estándar de 0.8589109 , siendo una variable homogénea, cuyos valores se concentran en la parte media alta de la variable con la agregación de valores atípicos de 112 outliers; por todo lo anterior, el comportamiento de la variable es regular.