Echo off or semicolon in GUI

This might be very basic (stupid) question but I will ask anyway. Does eat make sense to use echo off in a matlab GUI, and does it make the program run faster? Which is the preferred, echo off or semicolon after each function. And finally, how do I place/use the echo off in a GUI code. Thanks from a novice.

Answer 1

[OCDER]

• It makes sense to use echo off pretty much every time. Although echo on is used for debugging purposes, there are better way to debug code via error messages and the debugger.
• echo off is faster, no time spent printing message.
• always use semicolon to suppress function outputs. It should be a habit to use ";" as many programming languages uses the semicolon to end a statement.
• if you use semicolon, you don't have to place echo off in your GUI, unless you want it to turn echo on / off as part of a debugger option for your GUI.

[Birch]

Thanks for a great answer Donald. One final one: do you use semicolon after each line or only after the “function” line?

[Walter Roberson]

I routinely use semi-colon after every statement, except for the control statements and parts of control statements. For example,

if this > that
   do_something;
end

where some people might go as far as

if this > that;
   do_something;
end;

The editor will warn that some of those semi-colons are not needed.

There are some statements that cannot generate output, but I tend to put semi-colons after them anyhow:

hold on;
set(gca, 'XTick', 1:20);

I am inconsistent as to whether I put a semi-colon after a set() call. "set" can produce output in some uses.

[OCDER]

Here's an example of how I write code, based on another question I just answered. As you can see, no semicolon after the function line. Semicolon everywhere else, EXCEPT for, end, if, switch, case. When in doubt, use semicolon as it doesn't hurt.

function wordcount = getWords
str = 'jeff john 2lion lion2 this2that dog.';
strcell = regexpi(str, '\w*', 'match');

%Defining word as one that starts with a letter (this2that would still be a word)
wordloc = cellfun(@(x) ~isempty(regexpi(x(1), '[a-z]')), strcell);
wordcount = sum(wordloc);     %number of words
nonwordcount = sum(~wordloc); %number of non-words

%Displaying words
for j = 1:length(wordloc)
    if wordloc(j)
        fprintf('Is a word: %s\n', strcell{j});
    end
end

The Editor in Matlab should kind of give you warnings and suggestion for formatting code. Also try opening up some matlab built-in function to see how the pros do it, like :

open csvread

[Birch]

Hi Robert and Donald. Thanks a lot for the answers and examples. Great help.

[OCDER]

You're Welcome!