first commit

Author: cameronabrams

01/avg.py

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+# avg.py -- computes the column-wise average and standard deviation of a datafile
+# with an arbitrary number of parallel columns of data
+# 
+# an exercise in learning python
+#
+# cameron f abrams
+# cfa22@drexel.edu
+# (c) 2017
+# drexel university
+#
+from math import sqrt # so we can use math functions without "math.*"
+import fileinput # can only use fileinput functions with "fileinput.*"
+#import sys
+import string
+import numpy as np
+
+count = 0
+for line in fileinput.input():
+    # split the line into an array of fields
+    lst = line.split(" ");
+    # if this is the first line, set up the accumulators
+    if count == 0 :
+        nf = len(lst);
+        sum = np.zeros(nf)
+        sum2 = np.zeros(nf)
+    i = 0
+    for x in lst[:] :
+       sum[i] += float(x)
+       sum2[i] += float(x)*float(x)
+       i+=1
+
+    count += 1
+
+for i in range(nf):
+    sum[i] /= count
+    sum2[i] = sqrt((sum2[i] - sum[i]*sum[i]/count)/count)
+
+print 'Averages:',
+for i in range(nf):
+    print ' {0:.5f}'.format(sum[i]),
+print
+print 'Std. Devs.:',
+for i in range(nf):
+    print ' {0:.5f}'.format(sum2[i]),
+print
+
+

01/data1

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+1.234 4.321 8.765
+2.345 5.432 5.432
+5.678 8.765 1.090

README.md

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+# Python exercises