擅长:python、mysql、java
<p>我写了这样的东西,似乎对y'=y^2-x有效</p>
<pre><code>from pylab import *
xmax = 4.0
xmin = -xmax
D = 20
ymax = 4.0
ymin = -ymax
x = linspace(xmin, xmax, D)
y = linspace(ymin, ymax, D)
X, Y = meshgrid(x, y)
deg = arctan(Y**2 - X)
QP = quiver(X,Y,cos(deg),sin(deg))
show()
</code></pre>
<p><img src="https://i.stack.imgur.com/ODc3T.png" alt="enter image description here"/></p>