Macro plotting examples

This chapter consists of a series of examples demonstrating how to plot graphics from inside a macro.

The complete set of pyplot examples can be found here

import math

import numpy
from numpy import linspace, random
from scipy.integrate import quad
from scipy.special import j0

from sardana.macroserver.macro import Type, macro


def j0i(x):
    """Integral form of J_0(x)"""

    def integrand(phi):
        return math.cos(x * math.sin(phi))

    return (1 / math.pi) * quad(integrand, 0, math.pi)[0]


@macro()
def J0_plot(self):
    """Sample J0 at linspace(0, 20, 200)"""
    x = linspace(0, 20, 200)
    y = j0(x)
    x1 = x[::10]
    y1 = list(map(j0i, x1))
    self.pyplot.plot(x, y, label=r"$J_0(x)$")
    self.pyplot.plot(x1, y1, "ro", label=r"$J_0^{integ}(x)$")
    self.pyplot.title(
        r"Verify $J_0(x)=\frac{1}{\pi}\int_0^{\pi}\cos(x \sin\phi)\,d\phi$"
    )
    self.pyplot.xlabel("$x$")
    self.pyplot.legend()
    self.pyplot.draw()


@macro()
def random_image(self):
    """Shows a random image 32x32"""
    img = random.random((32, 32))
    self.pyplot.matshow(img)
    self.pyplot.draw()


@macro([["interactions", Type.Integer, None, ""], ["density", Type.Integer, None, ""]])
def mandelbrot(self, interactions, density):
    x_min, x_max = -2, 1
    y_min, y_max = -1.5, 1.5

    x, y = numpy.meshgrid(
        numpy.linspace(x_min, x_max, density), numpy.linspace(y_min, y_max, density)
    )

    c = x + 1j * y
    z = c.copy()

    fractal = numpy.zeros(z.shape, dtype=numpy.uint8) + 255

    for n in range(interactions):
        z *= z
        z += c
        mask = (fractal == 255) & (abs(z) > 10)
        fractal[mask] = 254 * n / interactions
    self.pyplot.imshow(fractal)
    self.pyplot.draw()