Fix radical strings

Author: kg583

tests/tivars.py

@@ -435,6 +435,13 @@ def test_exact_matrix(self):
         self.assertEqual(test_matrix.matrix(), test_array)
         self.assertEqual(list(iter(test_matrix)), [entry for row in test_array for entry in row])
 
+        self.assertEqual(str(test_matrix), string := "[[3π, 3√10], [1/2, (4√5+2√3)/7]]")
+        self.assertEqual(f"{test_matrix:t}", "[[3π,3sqrt(10)][1n/d2,(4sqrt(5)+2sqrt(3))n/d7]]")
+
+        test_matrix.clear()
+        test_matrix.load_string(string)
+        self.assertEqual(test_matrix.matrix(), test_array)
+
 
 class SettingsTests(unittest.TestCase):
     def test_window(self):

tivars/types/real.py

@@ -74,7 +74,7 @@ def __format__(self, format_spec: str) -> str:
             case _:
                 if format_spec.endswith("t"):
                     spec = "" if format_spec == "t" else format_spec[:-1] + "f"
-                    return squash(re.sub(r"(√\d*)", r"sqrt(\1)", replacer(format(self, spec), {"-": "~", "/": "n/d"})))
+                    return squash(re.sub(r"√(\d*)", r"sqrt(\1)", replacer(format(self, spec), {"-": "~", "/": "n/d"})))
 
                 try:
                     return format(self.decimal(), format_spec)