Error in a function automatically generated by matlabFunction

Hi everyone. I'm working with a large symbolic matrix and I converted this matrix in a function with matlabFunction command. After 8 hours of processing, MATLAB give me a function that doesn't work. This is the error:

>> A_lin(1e-5, 1e-5, 1e-5, 0, 0, 0, 1, 9.81, 1, 1, 0.1, 0.1, 0.5)
Unrecognized function or variable 'beta_Var'.

Error in A_lin (line 509)
A =
ft_1({L,beta_Var,beta_r,g,k,m,t10,t100,t101,t104,t1043,t1047,t1048,t1049,t105,t1052,t106,t107,t1074,t1075,t108,t1085,t1088,t1089,t109,t1092,t11,t110,t111,t112,t1123,t1127,t113,t1133,t1134,t114,t1140,t115,t1170,t1176,t1177,t118,t1181,t1183,t119,t12,t121,t122,t124,t125,t1258,t126,t1265,t1266,t1267,t1268,t1269,t1277,t1281,t129,t13,t130,t132,t1327,t134,t1348,t135,t1354,t136,t137,t138,t139,t1398,t14,t140,t1403,t1404,t142,t143,t144,t1456,t146,t1462,t1463,t147,t1473,t1474,t148,t149,t15,t151,t153,t1533,t1547,t156,t157,t158,t1591,t1595,t1596,t16,t160,t1608,t161,t1610,t1611,t164,t165,t1663,t1689,t1698,t17,t170,t171,t172,t173,t1735,t1738,t1739,t1749,t1753,t179,t1793,t1794,t18,t1808,t181,t1813,t1814,t1815,t1816,t1818,t182,t1825,t1826,t1827,t1828,t1829,t1833,t1834,t1836,t187,t188,t189,t19,t190,t191,t192,t193,t1970,t1986,t1987,t199,t1999,t2,t20,t200,t201,t2011,t202,t204,t205,t206,t208,t209,t21,t210,t22,t220,t222,t223,t224,t225,t23,t238,t239,t24,t240,t241,t242,t246,t247,t248,t249,t25,t250,t251,t252,t255,t256,t26,t260,t262,t263,t265,t266,t267,t27,t273,t278,t279,t28,t280,t282,t284,t285,t286,t287,t288,t29,t292,t298,t30,t300,t301,t302,t303,t304,t305,t307,t308,t309,t31,t310,t311,t312,t313,t318,t319,t32,t320,t322,t323,t324,t325,t33,t331,t332,t335,t336,t337,t339,t34,t340,t341,t342,t343,t344,t346,t347,t348,t349,t35,t352,t353,t355,t356,t357,t36,t360,t361,t362,t363,t364,t366,t367,t369,t37,t370,t371,t376,t377,t378,t379,t38,t386,t387,t388,t389,t39,t392,t393,t395,t399,t4,t40,t400,t401,t402,t403,t407,t409,t41,t411,t412,t415,t416,t417,t418,t42,t420,t421,t422,t428,t429,t43,t432,t434,t44,t440,t443,t445,t447,t449,t45,t451,t452,t46,t469,t47,t470,t476,t48,t483,t49,t498,t5,t50,t501,t503,t504,t507,t51,t514,t518,t52,t524,t527,t533,t534,t55,t551,t554,t559,t56,t560,t561,t562,t57,t58,t59,t60,t609,t61,t62,t63,t64,t65,t66,t67,t68,t686,t688,t69,t7,t70,t71,t72,t73,t74,t75,t76,t77,t78,t787,t79,t790,t8,t80,t81,t82,t83,t830,t834,t835,t838,t84,t846,t85,t853,t855,t87,t88,t883,t884,t887,t888,t89,t9,t90,t905,t906,t908,t91,t92,t922,t926,t928,t93,t95,t96,t963,t967,t968,t97,t970,t971,t977,t98,t981,t983,t984,t985,t99,t993,t996,t997,t998,theta0,theta0_dot,theta1,theta1_dot,theta_r_dot});

[KSSV]

Did you define the input variable beta_Var?

What you have shown is a prt of the code, not the full code.

[Daniele Caradonna]

Nope! The signature of A_lin is:

A_lin(theta_r, theta_0, theta_1, theta_dot_r, theta_dot_0, theta_dot_1, m, g, k, L, D, beta, beta_r)

[Daniele Caradonna]

Inside automatially generated function, MATLAB declare a new variable beta_Var instead of beta.

Answer 1

[Walter Roberson]

If you look at https://www.mathworks.com/matlabcentral/answers/513625-how-to-save-a-symbolic-equation-in-a-txt-file#comment_817290 then you will see that inside the Symbolic Engine, MATLAB sometimes uses beta_Var when the user requested beta . Then the MATLAB level is usually responsible for mapping beta_Var back to beta .

MATLAB uses beta_Var to avoid conflict with the beta() function.

There might be bugs that lead to beta_Var not being renamed to beta sometimes.

The work-around is to rename your symbolic variable from beta to something else.