MATLAB graphics drawing-set coordinate scale

Set coordinate scale

We can use axiscommands to set the drawing range. The general commands are as follows:

aixs([xmin xmax ymin ymax])

Suppose we want to produce an image with a function y = sin(2x+3)in 0~5between, and ythe values we consider are between -1 and 1, then we can set yto display only these values:

>> x = [0:0.01:5];
>> y = sin(2*x + 3);
>> plot(x,y),axis([0 5 -1 1])

Now let's draw.
Try it first xin the range of 0 to 5, yin the range of -1 to 1:

>> x = [0:0.01:5];
>> y = exp(-1.5*x).*sin(5*x+3);
>> plot(x,y,'k'),axis([0 5 -1 1])

The image is as follows:

As you can see from the figure, ythe range can be adjusted again.
We try to yadjust the range to -0.7 ~ 0.3, so the axiscommand is changed to the following form:

>> plot(x,y,'k'),axis([0 5 -0.7 0.3])

The image now looks more compact.
Below we draw
the MATLABcorrect way to square the function in is to use array multiplication, that is, dot product:

for example:

>> y = sin(5*x).^2;

We use black dotted lines to draw:

>> x = [0:0.01:1];
>> y = sin(5*x).^2;
>> plot(x,y,'k:'),axis([0 1 0 1])

The picture is as follows:
xfunction image between 0 ~ 5:

review:

• axis equal Coordinate axes are equally spaced
• axis square Produces a square image