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Generate KDB / Q sequence similar to R seq (from, to, step)

Is there a way to generate a sequence of numbers with a given step, similar to the R seq (from, to, step) function?

eg.

> seq(1,20,2)   
[1]  1  3  5  7  9 11 13 15 17 19
+3


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4 answers


user2393012's answer is close, but not quite what you were looking for. The following works well -



q)seq:{x+z*til ceiling(1+y-x)%z}
q)seq[1;20;2]
1 3 5 7 9 11 13 15 17 19
+4


source


Alternative (but not better than simple arithmetic solutions)



q){-1_(y>=)(z+)\x}[1;20;2]
1 3 5 7 9 11 13 15 17 19
+2


source


Just use arithmetic :-)

q){[step;start;length] start+step*til length}[2;0;10]
0 2 4 6 8 10 12 14 16 18
q){[step;start;length] start+step*til length}[3;0;10]
0 3 6 9 12 15 18 21 24 27
+1


source


Another option (a slight modification of terrylynch's solution ):

q) {(z+)\[floor(y-x)%z;x]} [1;20;2]
1 3 5 7 9 11 13 15 17 19
+1


source






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