爲什麼在Matlab語法錯誤？

Question

我打算使用bitsra()函數來執行算術右移操作。但是Matlab解釋認爲我的腳本錯誤。 Mathworks的手冊在這個問題上保持沉默。我很抱歉發佈了我的整個代碼，但是當我從整個代碼中提取錯誤代碼的一部分，然後讓解釋器執行錯誤部分時，它就可以工作。我不知道爲什麼會發生此錯誤。您可能會在標記爲「％error error error」的整個代碼中看到錯誤的部分。

% x^3 + 4x^2 - 10 
% linear approximation f(x)=f(x0)+f'(x0)(x-x0)  at x=x0 
function [ y ] = polynomial(x, scale_factor) % x is scaled by scale_factor. 
% POLYNOMIAL Summary of this function goes here 
% Detailed explanation goes here 

% determine x0 near x. 
if(x > int16(1.5 * scale_factor)) 
    x0 = int16(1.75 * 4); % set x0 to 1.75 if x is between 1.5 and 2 
else 
    x0 = int16(1.25 * 4); % set x0 to 1.25 if x is between 1 and 1.5 
end 


x0_square = int16(x0 .* x0); % scale factor : 2^4 
x0_square_11 = x0_square .* 2.^7; % this variable is scaled by 2^11. 



x_10 = int16(x); 
x_10 = bitsra(x_10, 1); % scale factor : 2^10 
x0_10 = x0 .* 2.^8; % scale factor : 2^10 

% linear approximation of x square near x0 
%    should be 11    1      10  
x_square_a = int16(x0_square_11 + (bitsra(2 .* x0, 1) .* (x_10 - x0_10))); % scale_factor : 2^11 


% error error error 
x_9 = bistra(x_10, 1); % scale factor : 2^9 
x0_9 = bitsra(x0_10, 1); % scale factor : 2^9 


x0_cubic = int16(x0_square .* x0); % scale factor : 2^6 
x0_cubic_13 = x0_cubic .* 2.^7; % scale factor : 2^11 
% linear approximation of x cubic near x0 
%    13       4     9 
x_cubic_a = int16(x0_cubic_13 + (((3 .* x0_square) .* (x_9 - x0_9)))); 
x_cubic_a = bitsra(x_cubic_a, 2); % scale factor : 2^11 

constant_term = int16(10 .* scale_factor); 

y = int16(x_cubic_a + 4 .* x_square_a - constant_term); 

end 

Matlab的給

Undefined function 'bistra' for input arguments of type 'int16'. 

Error in polynomial (line 30) 
x_9 = bistra(x_10, 1); % scale factor : 2^9 

Answer 1

變化bistra到bitsra在線30 polynomial。錯誤不能更清楚地說明什麼是錯誤的。

它的下面一行：

x_9 = bistra(x_10, 1); % scale factor : 2^9