fix parse bug

core functions/preprocess/Ulit/dinterptable.m

@@ -7,7 +7,35 @@ function h = dinterptable(X, Y, u)
 % b(b == 0) = 1;
 % b(b == n) = n - 1;
 % h = DYDX(b);
+X = X(:);
+Y = Y(:);
+u = u(:);
+
+if numel(X) ~= numel(Y)
+    error('dinterptable:SizeMismatch', ...
+        'X and Y must have the same length. Got %d and %d.', numel(X), numel(Y));
+end
+if any(~isfinite(X)) || any(~isfinite(Y))
+    error('dinterptable:InvalidTable', ...
+        'Interpolation table contains NaN or Inf.');
+end
+if any(diff(X) < 0)
+    error('dinterptable:NonMonotonicX', ...
+        'Interpolation table X must be nondecreasing.');
+end
+
 DYDX = diff(Y) ./ diff(X);
 DYDX = DYDX([1, 1:end, end]);
 [~, b] = histc(u, [-inf;X;inf]);
+
+invalid_mask = ~isfinite(u) | b < 1 | b > numel(DYDX);
+if any(invalid_mask)
+    bad_values = u(invalid_mask);
+    bad_preview = bad_values(1:min(5, numel(bad_values)));
+    error('dinterptable:InvalidQuery', ...
+        ['Interpolation query contains invalid values. ' ...
+         'num_bad=%d, sample=%s, X_range=[%g, %g], Y_range=[%g, %g].'], ...
+        numel(bad_values), mat2str(bad_preview.'), X(1), X(end), min(Y), max(Y));
+end
+
 h = reshape(DYDX(b), [], 1);