float eval_branch(struct node *node, float x, float y, float z, float a) { switch (node->token) { case token_x: return x; case token_y: return y; case token_z: return z; case token_a: return a; case token_num: return node->value; case token_pow: return func_pow(eval_branch(node->left, x, y, z, a), node->value); case token_mul: return func_mul(eval_branch(node->left, x, y, z, a), eval_branch(node->right, x, y, z, a)); case token_div: return func_div(eval_branch(node->left, x, y, z, a), eval_branch(node->right, x, y, z, a)); case token_add: return func_add(eval_branch(node->left, x, y, z, a), eval_branch(node->right, x, y, z, a)); case token_sub: return func_sub(eval_branch(node->left, x, y, z, a), eval_branch(node->right, x, y, z, a)); case token_neg: return func_neg(0, eval_branch(node->right, x, y, z, a)); case token_sqrt: return func_sqrt(0, eval_branch(node->right, x, y, z, a)); case token_sin: return func_sin(0, eval_branch(node->right, x, y, z, a)); case token_cos: return func_cos(0, eval_branch(node->right, x, y, z, a)); default: return 0; } }
func_t *func_diff_tan_pow1(func_t *f, int var) { func_t *fx=NULL,*g=NULL,*gx=NULL; if(!func_is(f,"tan") || func_power(f)!=1){ FUNC_ERROR_ARG1("func_diff_tan",f); } g=f->a[0]; gx=func_diff(FR(g),func_var1(var,1)); fx=func_mul(func_pow_n(func_cos(FR(g)),-2),gx); f=func_del(f); return fx; }