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
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
|
#!/usr/bin/env python
import csv
import getopt
import os, sys
import scipy.interpolate
import numpy as np
import matplotlib.pyplot as plt
INTERP_METHODS = [ 'cubic', 'linear' ]
DEFAULT_N = 100
def usage():
print("""usage: {} [OPTION...] CSV-FILE...
-d DIR use DIR as output directory (default: same as input file)
-f force overwrite of existing files
-i INTERP use interpolation method INTERP. Must be one of: {} (default: {})
-N N produce N data points in the output (default: {})
-p plot result (default: off)
-h show this help and exit""".format(os.path.basename(sys.argv[0]),
','.join(INTERP_METHODS), INTERP_METHODS[0], DEFAULT_N))
def main():
try:
opts, args = getopt.getopt(sys.argv[1:], "d:fi:N:ph")
except getopt.GetoptError, err:
print(str(err))
usage()
sys.exit(-1)
if len(args) < 1:
usage()
sys.exit(-1)
output_dir = None
force = False
interp = INTERP_METHODS[0]
N = DEFAULT_N
do_plot = False
x_max = 100
y_max = 50
for o, a in opts:
if o == '-d':
if os.path.exists(a):
output_dir = a
else:
print("Error: output directory {} is not a valid path".format(a))
sys.exit(-1)
elif o == '-f':
force = True
elif o == '-i':
if a in INTERP_METHODS:
interp = a
else:
print("Error: invalid interpolation method: {}".format(a))
usage()
sys.exit(-1)
elif o == '-N':
try:
N = int(a)
except ValueError:
print("Error: invalid number of data points: {}".format(N))
usage()
sys.exit(-1)
elif o == '-p':
do_plot = True
elif o == '-h':
usage()
sys.exit(0)
else:
assert False, "unhandled option"
for csv_file in args:
if not os.path.exists(csv_file):
print("Error: File {} not found, skipping".format(csv_file))
continue
with open(csv_file, 'r') as cf:
dialect = csv.Sniffer().sniff(cf.read(1024))
cf.seek(0)
csv_reader = csv.reader(cf, dialect)
x_name, y_name = csv_reader.next() # header line
X = np.array([[float(_x), float(_y)] for _x, _y in csv_reader ])
x = X[:,0]
y = X[:,1]
# TODO: maybe smoothen data first?
# interpolate data points
xnew = np.linspace(min(x), max(x), N)
f = scipy.interpolate.interp1d(x, y, kind=interp)
ynew = f(xnew)
if do_plot:
plt.plot(x, y, 'x')
plt.plot(xnew, ynew, '-')
plt.legend([ 'data', "{} interpolation".format(interp) ], loc='best')
plt.axis([ 0, x_max, 0, y_max ], 'equal')
plt.xlabel(x_name)
plt.ylabel(y_name)
plt.title(csv_file)
plt.grid(True)
plt.show()
Y = np.transpose(np.array([ xnew, ynew ]))
if output_dir:
od = output_dir
else:
od = os.path.dirname(csv_file)
out_file = os.path.join(od, os.path.basename(csv_file) + '.interp')
if os.path.exists(out_file) and not force:
print("Error: file {} already exists, not overwriting".format(out_file))
else:
csv_writer = csv.writer(open(out_file, 'w'), dialect)
csv_writer.writerow([ x_name, y_name ])
csv_writer.writerows(Y)
if __name__ == '__main__':
main()
|
