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--- other:python:misc_by_jyp [2022/02/21 16:15] – [numpy related stuff] jypeter
+++ other:python:misc_by_jyp [2022/02/21 17:31] – [numpy related stuff] Added ufuncs jypeter
@@ Line 253: / Line 253: @@
 .5
 >>> vals.sum() # The usual and easy way to do it
-.5</code>
+.5
+# Compute the sum of the elements of 'nb_unique'
+# AND keep (accumulate) the intermediate results
+>>> nb_unique
+array([3, 3, 4])
+>>> np.add.accumulate(nb_unique)
+array([ 3,  6, 10])
+# The accumulated values can be used as indices to separate the different groups of sorted values!
+>>> sorted_vals
+array([1. , 1. , 1. , 1.5, 1.5, 1.5, 2. , 2. , 2. , 2. ])
+>>> sorted_vals[0:3]
+array([1., 1., 1.])
+>>> sorted_vals[3:6]
+array([1.5, 1.5, 1.5])
+>>> sorted_vals[6:10]
+array([2., 2., 2., 2.])
+# Compute the sum of each equal-value group
+>>> sorted_vals[0:3].sum(), sorted_vals[3:6].sum(), sorted_vals[6:10].sum()
+(3.0, 4.5, 8.0)</code>
 /*