global variables not cleared after 'clear;clc'

I have a global variable. I run the code for several times. I put 'clear;clc' at the front. Strangely before the global variable is called, it already has a value. However I rerun it, it always has a value before its line is called. What could've happened?

Answer 1

[Walter Roberson]

clear by itself only removes variables from the current workspace not the global workspace . You need to

clear global

[madhan ravi]

Exactly as sir Walter says, that’s why most of the matlab experts do not recommend global variables.

[Walter Roberson]

This aspect is relatively far down on my reasons for not recommending global variables. ;-)

[madhan ravi]

I agree sir Walter , what I mean't was using global variables makes debugging difficult causing a lot of confusions.

[a a]

I love using global variables to save writing functions with a long list of argin's. Is it a legitimate reason?

[Walter Roberson]

using global variables to save writing functions with a long list of argin's. Is it a legitimate reason?

There is a big difference between "legitimate" reasons and "good" reasons. Making a bad programming decision because your mind is muddled by your cold and flu medication is a "legitimate" reason. Delegating the decision to bald hampsters for cost-savings reasons is a "legitimate" reason. Using global variables because your astrologer slash homoepathic guru is a "legitimate" reason. But these are not good reasons.

If you want to save writing long lists of arguments, then there are multiple strategies, including using nested functions with shared variables.