No more copying of the entire matrix

src/nim_word_prediction.nim

@@ -9,11 +9,13 @@ proc predict(word:string, matrix:Matrix[uint16],
     return ""
   let
     w = word2int[word]
-    rowW = matrix.row(w)
   var
     maxI = 0
     maxW = 0u16
-  for i, x in rowW:
+
+  # Get the maximum of that row
+  for i in 0 .. matrix.N - 1:
+    let x = matrix[w, i]
     if x > maxW:
       maxI = i
       maxW = x
@@ -22,6 +24,7 @@ proc predict(word:string, matrix:Matrix[uint16],
 proc updateMatrix(matrix:var Matrix[uint16], word1:string, word2:string,
                   word2int:var TableRef[string, int],
                   int2word:var TableRef[int, string]) =
+  # Index the words if the aren't in the index yet
   if not word2int.hasKey(word1):
     let newIndex = len(word2int)
     word2int[word1] = newIndex
@@ -30,10 +33,14 @@ proc updateMatrix(matrix:var Matrix[uint16], word1:string, word2:string,
     let newIndex = len(word2int)
     word2int[word2] = newIndex
     int2word[newIndex] = word2
+
+  # Compute the indices
   let
     w1 = word2int[word1]
     w2 = word2int[word2]
-  if w1 < 20000 and w2 < 20000:
+
+  # Check if the matrix is large enough
+  if w1 < matrix.ld and w2 < matrix.ld:
     matrix[w1, w2] += 1
 
 proc interactive(matrix:Matrix[uint16],
@@ -50,7 +57,7 @@ proc main() =
     statistics = false
     word = "I"
     texts:seq[string]
-    matrix = zeros(20000, 20000, uint16)
+    matrix = zeros(20000, 20000, uint16, rowMajor)
     word2int = newTable[string, int]()
     int2word = newTable[int, string]()