How do I create a regularly-spaced array of values

问题:

How do I make an array that's defined with a start point, an end point, and a total array size? Something like an array that goes from 1 to 10 that's 20 elements long. For example, the array could look something like:

1 1.5 2 2.5 3 3.5 ...

回答1:

There are a couple of ways you can do this:

• Using the colon operator:

  startValue = 1;
  endValue = 10;
  nElements = 20;
  stepSize = (endValue-startValue)/(nElements-1);
  A = startValue:stepSize:endValue;
  

• Using the linspace function (as suggested by Amro):

  startValue = 1;
  endValue = 10;
  nElements = 20;
  A = linspace(startValue,endValue,nElements);
  

Keep in mind that the number of elements in the resulting arrays includes the end points. In the above examples, the difference between array element values will be 9/19, or a little less than 0.5 (unlike the sample array in the question).

回答2:

linspace generates linearly spaced vectors:

>>  A = linspace(1, 10, 20-1)
ans =
1 1.5 2 2.5 3 3.5 ... 9.5 10

回答3:

Simple one-liner!

1:0.5:10;

Output:

1 1.5 2 2.5 ... 9 9.5 10

Note that this would be a 19-element vector, not 20.