how to define a while statement that when the variable equals a numerical value, ends the code?
显示 更早的评论
Hi,
I want to write a while condition that when variable A gets a numerical value inside the loop, ends the code, otherwise continues to the code...
How can I write this while condition?
Thansks in advance,
Regards...
采纳的回答
Walter Roberson
2016-1-19
while ~exist('A', 'var') && ~isnumeric(A)
...
end
This will continue to loop until A is assigned a value and the value is numeric.
The common kinds of values that are not numeric include logical values, character strings, structures, cell arrays, function handles, graphics objects (R2014b or later), and various other kinds of objects.
3 个评论
bilgesu ak
2016-1-19
Walter Roberson
2016-1-19
while ~exist('A', 'var') || ~isnumeric(A) || isempty(A)
...
end
You would not need to initialize A at all
[] is type double and so is considered a numeric value. However I have added that as a condition.
bilgesu ak
2016-1-19
更多回答（1 个）
Titus Edelhofer
2016-1-19
Hi,
I understand the "get's value" is meant as "being not empty" ...?
A = [];
while isempty(A)
% do something, e.g.
A = 42;
end
Titus
2 个评论
Titus Edelhofer
2016-1-19
Or, if you want to run while it's not a specified value:
A = 10;
while A~=1
% do something, e.g.
A = A - 1;
end
Titus
Walter Roberson
2016-1-19
And be careful, if your "specified value" is not an integer then it might be difficult to match it exactly due to floating point precision issues.
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