MATLAB: Join 2 tables with different values in the key variable

join;merge tablesouterjoin

I would like to join the tables:
A = 6 x 1 table      B = 4 x 2 table
    Var 1         Var 1    Var 2
    930         930      10
    931          935      3
    932          938      5
    935          940      7
    936
    939
The key variable (Var 1) do not have exactly the same values in Table A and B. I would like to join using the following rule:
Rule: For each value of Var 1 in Table A, find the value of Var 1 in Table 2 that is the MINIMUM and GREATER THAN OR EQUAL TO the value in Table A. Then join the corresponding row of Var 2 from Table B to Table A.
e.g. for 930, the minimum which is greater than or equal to 930 in Table B is 930, so 10 is joined to Table A.
for 931, the minimum which is greater than or equal to 931 in Table B is 935, so 3 is joined to Table A.
for 932, the minimum which is greater than or equal to 932 in Table B is 935, so 3 is joined to Table A.
for 935, the minimum which is greater than or equal to 935 in Table B is 935, so 3 is joined to Table A.
for 936, the minimum which is greater than or equal to 936 in Table B is 938, so 5 is joined to Table A.
for 939, the minimum which is greater than or equal to 939 in Table B is 940, so 7 is joined to Table A.
So the resulting Table A I want would be:
A = 6 x 2 table
  Var 1  Var 2
  930  10
  931  3
  932  3
  935  3
  936  5
  939  7
The outer join would not work for me because I cannot have NaN. What would be a good way to achieve this?
Not sure the text formatting here is clear so I attach a pdf for easy reading.

Best Answer

The way I would do it:
d = B.Var1 - A.var1';  %requires R2016b or later
d(d < 0) = Inf;
[~, idx] = min(d);
A.var2 = B.Var2(idx);
This will work as long as that there is always a value in B that is smaller or equal than the values in A.
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