Moving Ghosh function to CalculationFunction.R

R/CalculationFunctions.R

@@ -632,3 +632,73 @@ calculateTotalImpactbyTier1Purchases <- function(model, impact, opt_impact='indi
   })
   return(totalImpactPerPurchase)
 }
+
+
+# Function to get backward or forward economic linkages from a USEEIO model,
+# Provides results based on input demand, sorted by total (direct+indirect)
+# Backward linkages use A and L matrices
+# Forward linkages use Ghosh counterparts to A and L
+#' @param model An EEIO model object with model specs, IO tables, satellite tables, and indicators loaded
+#' @param demand demand vector
+#' @param type "backward" linkages use A and L matrices "forward" linkages use Ghosh counterparts to A and L
+#' @param use_domestic_requirements A logical value: if TRUE, use domestic demand and L_d matrix;
+#' if FALSE, use complete demand and L matrix.
+#' @param location str optional location code for demand vector, required for two-region models
+#' @param cutoff numeric value, shows the cutoff value for sorted results. Values smaller than cutoff are not shown
+
+getSectorLinkages <- function(model, demand, type="backward", location = NULL, use_domestic_requirements=FALSE,cutoff=0.01) {
+  f <- prepareDemandVectorForStandardResults(model, demand, location, use_domestic_requirements)
+  if(type=="backward") {
+    if (use_domestic_requirements) {
+      tier1 <- model$A_d %*%f 
+      all <- model$L_d %*%f  
+    }  else {
+      tier1 <- model$A%*%f 
+      all <- model$L%*%f   
+    }
+  } else if(type=="forward") {
+    Ghosh_B <- calculateGhoshB(model,use_domestic_requirements)
+    Ghosh_G <- calculateGhoshG(Ghosh_B)
+    tier1 <- Ghosh_B%*%f 
+    all <- Ghosh_G%*%f  
+  }
+  tier2andbeyond <- all-tier1
+
+  # Remove the additional "1" from the Leontief or Ghosh to avoid double counting indirect 
+  tier2andbeyond <- tier2andbeyond-f
+  total <- tier1 + tier2andbeyond
+
+  linkages <- data.frame(direct=tier1,indirect=tier2andbeyond,total=total)
+  linkages$Name <- model$Commodities[match(rownames(linkages),
+                                           model$Commodities$Code_Loc),"Name"]
+  # Filter by share > 1%
+  linkages <- linkages[linkages$total > cutoff, ]
+  # Sort them
+  linkages <- linkages[order(linkages$total, decreasing = TRUE),]
+  return(linkages)
+}
+
+#function to get supply side Ghosh matrix B
+#' @param model An EEIO model object with model specs, IO tables, satellite tables, and indicators loaded
+#' @param use_domestic_requirements A logical value: if TRUE, use domestic demand and L_d matrix;
+#' if FALSE, use complete demand and L matrix.
+calculateGhoshB <- function(model,use_domestic_requirements=FALSE) {
+  x <- model$q
+  if (use_domestic_requirements) {
+    A <- model$A
+  } else {
+    A <- model$A_d
+  }
+
+  B <- solve(diag(x)) %*% A %*% diag(x)
+  row.names(B) <- model$Commodities$Code_Loc
+  colnames(B) <- model$Commodities$Code_Loc
+  return(B)
+}
+
+# function to calculate inverse of Ghosh matrix B, returns the inverse G
+#' @param B Ghosh matrix B
+calculateGhoshG <- function(GhoshB) {
+  G <- useeior:::calculateLeontiefInverse(GhoshB)
+  return(G)
+}