added param type check + some functions

src/config.typ

@@ -0,0 +1 @@
+#let PRECISION = 6

src/lib.typ

@@ -1,2 +1,4 @@
 #import "mat.typ"
 #import "vec.typ"
+
+#import "gauss.typ"

src/mat.typ

@@ -1,4 +1,19 @@
+#import "config.typ"
+
+#let is-mat(mat) = {
+  if type(mat) != dictionary {return false}
+  if mat.at("type", default: none) != "matrix" {return false}
+  return true
+}
+
+#let _check(mat) = {
+  if not is-mat(mat) {
+    panic("Argument is not a matrix")
+  }
+}
+
 #let size(mat) = {
+  _check(mat)
   return str(mat.h) + "x" + str(mat.w)
 }
 
@@ -11,20 +26,31 @@
     panic("All rows should have the same length")
   }
   return (
+    type: "matrix",
     rows: rows,
     w: w,
     h: h
   )
 }
 
+#let copy(original) = {
+  _check(original)
+  return mat(..original.rows)
+}
+
 #let of-size(h, w) = {
   let rows = ((0,) * w,) * h
   return mat(..rows)
 }
 
-#let display(mat) = math.mat(..mat.rows)
+#let display(mat) = {
+  _check(mat)
+  math.mat(..mat.rows)
+}
 
 #let add(mat1, mat2) = {
+  _check(mat1)
+  _check(mat2)
   if mat1.w != mat2.w or mat1.h != mat2.h {
     panic("Can't add matrices of size " + size(mat1) + " and " + size(mat2))
   }
@@ -41,6 +67,8 @@
 }
 
 #let sub(mat1, mat2) = {
+  _check(mat1)
+  _check(mat2)
   if mat1.w != mat2.w or mat1.h != mat2.h {
     panic("Can't subtract matrices of size " + size(mat1) + " and " + size(mat2))
   }
@@ -57,6 +85,8 @@
 }
 
 #let mul(mat1, mat2) = {
+  _check(mat1)
+  _check(mat2)
   if mat1.w != mat2.h {
     panic("Can't multiply matrices of size " + size(mat1) + " and " + size(mat2))
   }
@@ -77,6 +107,7 @@
 }
 
 #let transpose(mat) = {
+  _check(mat)
   let mat-t = of-size(mat.w, mat.h)
 
   for y in range(mat.h) {
@@ -89,11 +120,13 @@
 }
 
 #let to-vec(mat) = {
+  _check(mat)
   import "vec.typ" as _vec
   return _vec.vec(..mat.rows.map(r => r.first()))
 }
 
 #let mul-vec(mat1, vec) = {
+  _check(mat1)
   import "vec.typ" as _vec
 
   if mat1.w != vec.size {
@@ -105,3 +138,50 @@
 
   return to-vec(res)
 }
+
+#let mul-row(mat1, row, f) = {
+  _check(mat1)
+  let mat2 = copy(mat1)
+
+  for x in range(mat1.w) {
+    mat2.rows.at(row).at(x) *= f
+  }
+
+  return mat2
+}
+
+#let div-row(mat1, row, f) = {
+  _check(mat1)
+  if f == 0 {
+    panic("Can't divide by 0")
+  }
+
+  return mul-row(mat1, row, 1/f)
+}
+
+#let add-row(mat1, row1, row2, f: 1) = {
+  _check(mat1)
+  let mat2 = copy(mat1)
+
+  for x in range(mat1.w) {
+    mat2.rows.at(row1).at(x) += mat1.rows.at(row2).at(x) * f
+  }
+
+  return mat2
+}
+
+#let round(mat) = {
+  _check(mat)
+  let mat2 = copy(mat)
+
+  for y in range(mat2.h) {
+    for x in range(mat2.w) {
+      mat2.rows.at(y).at(x) = calc.round(
+        mat2.rows.at(y).at(x),
+        digits: config.PRECISION
+      )
+    }
+  }
+
+  return mat2
+}

src/vec.typ

@@ -1,20 +1,43 @@
+#let is-vec(vec) = {
+  if type(vec) != dictionary {return false}
+  if vec.at("type", default: none) != "vector" {return false}
+  return true
+}
+
+#let _check(vec) = {
+  if not is-vec(vec) {
+    panic("Argument is not a vector")
+  }
+}
+
 #let vec(..args) = {
   let comps = args.pos()
   let size = comps.len()
   return (
+    type: "vector",
     comps: comps,
     size: size
   )
 }
 
+#let copy(vec) = {
+  _check(vec)
+  return vec(..vec.comps)
+}
+
 #let of-size(size) = {
   let comps = (0,) * size
   return vec(..comps)
 }
 
-#let display(vec) = math.vec(..vec.comps.map(c => [#c]))
+#let display(vec) = {
+  _check(vec)
+  math.vec(..vec.comps.map(c => [#c]))
+}
 
 #let add(vec1, vec2) = {
+  _check(vec1)
+  _check(vec2)
   if vec1.size != vec2.size {
     panic("Can't add vectors of size " + str(vec1.size) + " and " + str(vec2.size))
   }
@@ -24,6 +47,8 @@
 }
 
 #let sub(vec1, vec2) = {
+  _check(vec1)
+  _check(vec2)
   if vec1.size != vec2.size {
     panic("Can't subtract vectors of size " + str(vec1.size) + " and " + str(vec2.size))
   }
@@ -33,6 +58,8 @@
 }
 
 #let dot(vec1, vec2) = {
+  _check(vec1)
+  _check(vec2)
   if vec1.size != vec2.size {
     panic("Can't compute dot product of vectors of size " + str(vec1.size) + " and " + str(vec2.size))
   }
@@ -45,6 +72,8 @@
 }
 
 #let cross(vec1, vec2) = {
+  _check(vec1)
+  _check(vec2)
   if vec1.size != 3 or vec2.size != 3 {
     panic("Can only compute cross product of vectors of size 3")
   }
@@ -60,6 +89,7 @@
 }
 
 #let to-mat(vec) = {
+  _check(vec)
   import "mat.typ" as _mat
   return _mat.mat(..vec.comps.map(c => (c,)))
 }