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I have a dataset, where some data has to be ranked in regard to the number of ranking of the total dataset. I've made a simple example below:

names = {"Set A", "Set B", "Set C"};
values = {67, 80, 50};
{names, values} // Transpose

I would like to add a 3rd column, which described the rank of the total column. I've tried with RankedMax but without any luck. To be more exactly, the matrix below shows my problem, where the third column is ranking the highest to lowest value.

$$\left( \begin{array}{ccc} \text{Set 1} & 67 & 2 \\ \text{Set 2} & 80 & 1 \\ \text{Set 3} & 50 & 3 \\ \end{array} \right)$$

How can create such a column?

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  • $\begingroup$ Does {names, values, Ordering[values]} // Transpose work to get what you need? $\endgroup$
    – kglr
    Commented May 18, 2014 at 14:03
  • $\begingroup$ @kguler this is exactly what I needed. Very Simple I see. Thank you. Maybe I should delete this post? I suppose this will not add any value to others, since it is this simple... $\endgroup$
    – Jens Jensen
    Commented May 18, 2014 at 14:08
  • $\begingroup$ @kguler I guess that should be Ordering[-values], given that the OP wants a descending sort $\endgroup$
    – Sjoerd C. de Vries
    Commented May 18, 2014 at 14:09
  • $\begingroup$ @kguler After further investigation, I can see that Ordering doesn't solve the problem for all kinds of dataset, especially when they become larger than this example.. $\endgroup$
    – Jens Jensen
    Commented May 18, 2014 at 14:26
  • $\begingroup$ Jens, what kind of issues do you get with Ordering for larger datasets? $\endgroup$
    – kglr
    Commented May 18, 2014 at 14:34

1 Answer 1

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The data set you pasted in your comment below contained several invisible non-ASCII characters.

They are revealed using ToCharacterCode

dataString = "{0.109892,0.153395,0.263218,0.0976219,0.26596,0.230077,0.235412,0.201642,0.07021‌​26,0.134909,0.155424,0.263319,0.224367,0.253994,0.117316,0.0733121,0.190985,0.305‌​341,0.139088,0.190262,0.00999462,0.20669,-0.00893785,0.087579,0.175154,0.0882176,‌​0.193825,0.236279,-0.0883605,0.229773,0.292539,0.0971533,0.0613749,0.298706,0.121‌​186,0.148439,0.000799421,0.284733,0.335953,-0.0610469,0.14451,0.0784617,0.136533,‌​0.37428,0.181673,0.262039,-0.217684,-0.13403,0.0359772,0.179099}"

ToCharacterCode[dataString]

(* {123, 48, 46, 49, 48, 57, 56, 57, 50, 44, 48, 46, 49, 53, etc. 49, 8204, \
8203, 50, 54, 44, etc. 48, 53, 8204, 8203,  etc. 44, 8204, 8203, 48, \
etc., 49, 8204, 8203, 49, 56, etc. 57, 125} *)

Convert to real ASCII:

data = DeleteCases[ToCharacterCode[dataString], _?(# > 127 &)] //FromCharacterCode // ToExpression
(* {0.109892, 0.153395, 0.263218, 0.0976219, 0.26596, 0.230077, \
0.235412, 0.201642, 0.0702126, 0.134909, 0.155424, 0.263319, \
0.224367, 0.253994, 0.117316, 0.0733121, 0.190985, 0.305341, \
0.139088, 0.190262, 0.00999462, 0.20669, -0.00893785, 0.087579, \
0.175154, 0.0882176, 0.193825, 0.236279, -0.0883605, 0.229773, \
0.292539, 0.0971533, 0.0613749, 0.298706, 0.121186, 0.148439, \
0.000799421, 0.284733, 0.335953, -0.0610469, 0.14451, 0.0784617, \
0.136533, 0.37428, 0.181673, 0.262039, -0.217684, -0.13403, \
0.0359772, 0.179099} *)

Ranking can be done using Ordering:

Ordering@Ordering@-data
(* {34, 26, 9, 35, 7, 14, 13, 18, 41, 31, 25, 8, 16, 11, 33, \
40, 20, 3, 29, 21, 44, 17, 46, 38, 24, 37, 19, 12, 48, 15, 5, 36, 42, \
4, 32, 27, 45, 6, 2, 47, 28, 39, 30, 1, 22, 10, 50, 49, 43, 23} *)

To show that this works, let's sort the paired data and ranking:

Transpose[{data, Ordering@Ordering@-data}] // Sort // Reverse
(* {{0.37428, 1}, {0.335953, 2}, {0.305341, 3}, {0.298706, 
  4}, {0.292539, 5}, {0.284733, 6}, {0.26596, 7}, {0.263319, 
  8}, {0.263218, 9}, {0.262039, 10}, {0.253994, 11}, {0.236279, 
  12}, {0.235412, 13}, {0.230077, 14}, {0.229773, 15}, {0.224367, 
  16}, {0.20669, 17}, {0.201642, 18}, {0.193825, 19}, {0.190985, 
  20}, {0.190262, 21}, {0.181673, 22}, {0.179099, 23}, {0.175154, 
  24}, {0.155424, 25}, {0.153395, 26}, {0.148439, 27}, {0.14451, 
  28}, {0.139088, 29}, {0.136533, 30}, {0.134909, 31}, {0.121186, 
  32}, {0.117316, 33}, {0.109892, 34}, {0.0976219, 35}, {0.0971533, 
  36}, {0.0882176, 37}, {0.087579, 38}, {0.0784617, 39}, {0.0733121, 
  40}, {0.0702126, 41}, {0.0613749, 42}, {0.0359772, 43}, {0.00999462,
   44}, {0.000799421, 45}, {-0.00893785, 46}, {-0.0610469, 
  47}, {-0.0883605, 48}, {-0.13403, 49}, {-0.217684, 50}} *)
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