1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
|
from pngcanvas import PNGCanvas
try:
from itertools import izip as zip
except ImportError:
pass
class SimpleLineChart(object):
def __init__(self, width, height, colours=None, legend=None):
self.canvas = PNGCanvas(width, height)
self.width = width
self.height = height
self.colours = colours
self.legend = legend
self.series = []
def add_data(self, series):
self.series.append(series)
def render(self):
max_width = max(map(len, self.series))
max_height = max(map(max, self.series))
x_scale = float(self.width) / max_width
y_scale = float(self.height) / max_height
data = zip(self.series, self.colours or [], self.legend or [])
for series, colour, legend in data:
colour = int(colour, 16)
self.canvas.color = (
colour>>16 & 0xff,
colour>>8 & 0xff,
colour & 0xff,
0xff,
)
last = None
for x, y in enumerate(series):
if y is not None:
y = self.height - y * y_scale
if last is not None:
x *= x_scale
self.canvas.line(x - x_scale, last, x, y)
last = y
def download(self, filename):
self.render()
f = open(filename, 'wb')
f.write(self.canvas.dump())
f.close()
|
