name as representing numbers

Consider

[Image Analyst]

I don't understand the examples. Why is J = 1, and K (the last/fourth letter) = 2??? And what kind of name is NOML, and how do you get the sequence 1,2,26, 25 for NOML? In the meantime, here are some helpful snippets:

vec = linspace('A', 'Z', 26)
name = 'Manav'
numbers = upper(name) - 'A' + 1

vec =

Columns 1 through 21

65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85

Columns 22 through 26

86 87 88 89 90

name =

'Manav'

numbers =

13 1 14 1 22

Answer 1

[Sindar]

I think the only change you need from Image Analyst's is to subtract off the (numeric code for the) first letter of the name, rather than the first letter of the alphabet, then ensure everything is positive.

name = 'Manav'
% get the numeric code for each letter, then shift so the first letter corresponds to 0
numbers = upper(name) - upper(name(1));
% map negatives to positive (e.g. -1 -> 26) and count from 1
numbers = mod(numbers,26) + 1;

[Walter Roberson]

numbers = mod(numbers,26) + 1;

Close but not quite. Consider 26. mod(26,26) is 0, and you would add 1 to get 1, whereas you would want to leave 26 as 26. For that matter, consider 1: mod(1,26) is 1, add the +1 to get 2, instead of leaving it alone as 1.

[Sindar]

That's why I don't add 1 in the line above. So, the first letter maps to 0, then mod(0,26)=0, then 1. While the letter before it maps to -1, then mod(-1,26)=25, then 26.