Fix #682 - strformat symbol binding bug with special matrices (#684)

* add necessary import for error messages

* remove uncessesary import

* ensure correct symbol binding

Author: lilkeet

src/arraymancer/linear_algebra/special_matrices.nim

@@ -4,7 +4,7 @@
 
 import ../tensor
 import ./helpers/triangular
-import std / [sequtils, bitops]
+import std / [sequtils, bitops, strformat]
 
 proc hilbert*(n: int, T: typedesc[SomeFloat]): Tensor[T] =
   ## Generates an Hilbert matrix of shape [N, N]
@@ -129,6 +129,7 @@ proc diagonal*[T](a: Tensor[T], k = 0, anti = false): Tensor[T] {.noInit.} =
   ##      - anti: If true, get the k-th "anti-diagonal" instead of the k-th regular diagonal.
   ## Result:
   ##      - A copy of the diagonal elements as a rank-1 tensor
+  bind `&`
   assert a.rank == 2, "diagonal() only works on matrices"
   assert k < a.shape[0], &"Diagonal index ({k=}) exceeds the output matrix height ({a.shape[0]})"
   assert k < a.shape[1], &"Diagonal index ({k=}) exceeds the output matrix width ({a.shape[1]})"
@@ -167,6 +168,7 @@ proc set_diagonal*[T](a: var Tensor[T], d: Tensor[T], k = 0, anti = false) =
   ##      - k: The index k of the diagonal that will be changed. The default is 0 (i.e. the main diagonal).
   ##        Use k>0 for diagonals above the main diagonal, and k<0 for diagonals below the main diagonal.
   ##      - anti: If true, set the k-th "anti-diagonal" instead of the k-th regular diagonal.
+  bind `&`
   assert a.rank == 2, "set_diagonal() only works on matrices"
   assert d.rank == 1, "The diagonal passed to set_diagonal() must be a rank-1 tensor"
   assert k < a.shape[0], &"Diagonal index ({k=}) exceeds input matrix height ({a.shape[0]})"
@@ -259,6 +261,7 @@ proc tri*[T](shape: Metadata, k: static int = 0, upper: static bool = false): Te
   ##               diagonal. The default is false.
   ## Result:
   ##      - The constructed, rank-2 triangular tensor.
+  bind `&`
   assert shape.len == 2, &"tri() requires a rank-2 shape as it's input but a shape of rank {shape.len} was passed"
   assert k < shape[0], &"tri() received a diagonal index ({k=}) which exceeds the output matrix height ({shape[0]})"
   assert k < shape[1], &"tri() received a diagonal index ({k=}) which exceeds the output matrix width ({shape[1]})"

tests/linear_algebra/test_linear_algebra.nim

@@ -2,7 +2,7 @@
 # Distributed under the Apache v2 License (license terms are at http://www.apache.org/licenses/LICENSE-2.0).
 
 import ../../src/arraymancer
-import std / [unittest, strformat]
+import std / [unittest]
 
 proc main() =
   suite "Linear algebra":

tests/linear_algebra/test_special_matrices.nim

@@ -2,7 +2,7 @@
 # Distributed under the Apache v2 License (license terms are at http://www.apache.org/licenses/LICENSE-2.0).
 
 import ../../src/arraymancer
-import std / [unittest, strformat]
+import std / [unittest]
 
 proc main() =
   suite "Diagonals":