Merge pull request #207 from mgreminger/inverse-units-fix

fix: fix matrix inverse units for mixed symbolic and numerical matrices
mgreminger · Aug 28, 2023 · 58d109c · 58d109c
2 parents 48ccbae + ab5b5e3
commit 58d109c
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Showing 2 changed files with 15 additions and 2 deletions.
diff --git a/public/dimensional_analysis.py b/public/dimensional_analysis.py
@@ -703,8 +703,12 @@ def ensure_inverse_dims(arg):
             row = []
             rows.append(row)
             for j in range(arg.cols):
-                row.append(cast(Expr, arg[j,i])**-1)
-                column_dims.setdefault(j, []).append(dimsys_SI.get_dimensional_dependencies(arg[i,j]))
+                dim, _ = get_mathjs_units(cast(dict[Dimension, float], dimsys_SI.get_dimensional_dependencies(arg[j,i])))
+                if dim == "":
+                    row.append(sympify('0'))
+                else:
+                    row.append(cast(Expr, arg[j,i])**-1)
+                column_dims.setdefault(i, []).append(dim)
 
         column_checks = []
         for _, values in column_dims.items():

diff --git a/tests/test_matrix_inverse.spec.mjs b/tests/test_matrix_inverse.spec.mjs
@@ -128,3 +128,12 @@ test('Inverse of large matrix with units', async () => {
   let content = await page.textContent(`#result-value-0`);
   expect(content).toBe(String.raw`\begin{bmatrix} 1 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 \\ 0 & 1 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 \\ 0 & 0 & 1 & 0 & 0 & 0 & 0 & 0 & 0 & 0 \\ 0 & 0 & 0 & 1 & 0 & 0 & 0 & 0 & 0 & 0 \\ 0 & 0 & 0 & 0 & 1 & 0 & 0 & 0 & 0 & 0 \\ 0 & 0 & 0 & 0 & 0 & 1 & 0 & 0 & 0 & 0 \\ 0 & 0 & 0 & 0 & 0 & 0 & 1 & 0 & 0 & 0 \\ 0 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 0 & 0 \\ 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 0 \\ 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 1 \end{bmatrix}`);
 });
+
+test('Inverse mixed symbolic units', async () => {
+  await page.setLatex(0, String.raw`\begin{bmatrix}1 & 0\\ -k & k\end{bmatrix}^{-1}\times\begin{bmatrix}1\\ F_2\end{bmatrix}=`);
+
+  await page.waitForSelector('text=Updating...', {state: 'detached'});
+
+  let content = await page.textContent(`#result-value-0`);
+  expect(content).toBe(String.raw`\begin{bmatrix} 1 \\ \frac{F_{2} + k}{k} \end{bmatrix}`);
+});