Undefined function or variable 'adaptthresh'

Inputimage=imread('im.jpg');

%% Convert to gray scale

Inputimage=rgb2gray(Inputimage);

% Convert to binary image

T = adaptthresh(Inputimage, 0.4);

BW = imbinarize(Inputimage,T);

figure(2)

imshow(Inputimage);

Answer 1

[madhan ravi]

https://in.mathworks.com/help/images/ref/adaptthresh.html?s_tid=answers_rc2-1_p4_MLT#bu2a9fp-1_seealso released in 2016a

[Mohamed Mansour]

how i can use it in 2015a ??

[Image Analyst]

You can't. You'll have to write your own if you don't want to upgrade.