How can I add the elements in the sublists?
For example, if I have the list which is
m={{1,3},{2,3},{4,1}}
then, the output that I want is 3+3+1=10.
How can I do this?
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5 Answers
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I thinks the cleanest way is:
Total@m[[All, 2]]
using Esc[[Esc and Esc]]Esc.
If you use it a lot (like me), you can create shortcuts as explained here.
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$\begingroup$ You can use these shortcuts if you don't like pressing
Escevery time forPartbrackets $\endgroup$– rm -rf ♦Commented Oct 30, 2012 at 14:27 -
$\begingroup$ Yes, I use it. I put in the post. Tks $\endgroup$– MurtaCommented Oct 30, 2012 at 18:46
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$\begingroup$ @Murta, I asked the Q on [[ ]] but find all the answers a pain. Can you make a palette button or single front-end command? $\endgroup$ Commented Nov 13, 2015 at 17:29
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Following @b.gatessucks
Total[m[[;; , 2]]]
(* 7 *)
If you want to sum all components (as @image_doctor pointed out too, sorry I missed that)
Plus @@@ Transpose[m]
(* 7 7 *)
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Total[m[[All , 2]]]works as well. :) $\endgroup$ Commented Oct 30, 2012 at 12:05
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Last@Total[{{1, 3}, {2, 3}, {4, 1}}]
or
Total[{{1, 3}, {2, 3}, {4, 1}}]
for both components
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{{1, 3}, {2, 3}, {4, 1}} // Query[Total, 2]
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Unfortunately the current Query and associated Dataset implementation is riddled with workarounds - this is going to tech support >>
{{1, 3}, {2, 3}, {4, 1}} // Query[Total, 2] // Trace // LeafCount
3175
Anyone interested in a timing study?
answered Nov 13, 2015 at 17:26
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{{1, 3}, {2, 3}, {4, 1}} // Query[Total, 2] // Trace // LeafCountresults in697as of May 2023. $\endgroup$– SyedCommented May 12, 2023 at 7:30
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Just For fun.
m = {{1, 3}, {2, 3}, {4, 1}}; Last[Total[m]]
Partto get the elements from the list, thenTotalto sum them up. $\endgroup$Plus @@@ (m\[Transpose])will give you a list of the sums of the various elements of your list. $\endgroup$