I have a complex nested list (depth can be >2 also):
p:((`g;`d1`d2);(`r;enlist `e1);(`r;enlist `p1))
How to add an element to each element of the nested list but retaining the original structure; e.g. adding `h to each element of p to get the following :
((`g`h;(`d1`h;`d2`h));(`r`h;enlist `e1`h);(`r`h;enlist `p1`h))
I tried this but doesn't give what I want :
q)p,\:`h
((`g;`d1`d2;`h);(`r;enlist `e1;`h);(`r;enlist `p1;`h))
q)raze[p],\:`h
(`g`h;`d1`d2`h;`r`h;`e1`h;`r`h;`p1`h)
You can use .z.s to recursively go through the nested list and only append `h to lists of symbols:
q){$[0=type x;.z.s'[x];x,\:`h]}p
g h d1 h d2 h
`r`h ,`e1`h
`r`h ,`p1`h
For this function I have made the assumption that your nested lists will only contain symbols. It checks the type of the list, if it is not a mixed list then it appends `h to each element. If it is a mixed list then it passes each element of that list back into the function separately to check again.
Although not recursive (and so requires some knowledge about the shape of your nested list), a more conventional approach would be
q).[p;2#(::);,';`h]
g h d1 h d2 h
`r`h ,`e1`h
`r`h ,`p1`h
Though Thomas has already answered the question; In case you want to specify any other operation apart from append, you can use the following :
q)f:{`$ "_" sv string x,y}
q){[o;a;e] $[-11<>type e; .z.s [o;a] each e; o[e;a]] }[f;`h] each p
`g_h `d1_h`d2_h
`r_h ,`e1_h
`r_h ,`p1_h
or when f is assigned as append operation
q)f:{x,y}
q){[o;a;e] $[-11<>type e; .z.s [o;a] each e; o[e;a]] }[f;`h] each p
g h d1 h d2 h
`r`h ,`e1`h
`r`h ,`p1`h
Related
With the following declarations:
uvec basis;
rowvec c;
sp_mat B;
The expression c(basis) seems to return an
arma::subview_elem1<double, arma::Mat<unsigned int> > and the following call appears to work:
vec pi_B = spsolve(trans(B), c(basis), "superlu");
How does spsolve resolve this input?
Also vec pi_B = spsolve(trans(B), trans(c(basis)), "superlu"); throws a dimensional mismatch error but the following runs:
rowvec d;
vec pi_B2 = spsolve(trans(B), trans(d), "superlu");
According to the documentation, c(basis) is a non-contiguous submatrix, where basis specifies which elements in c to use.
In this case c is "... interpreted as one long vector, with column-by-column ordering of the elements" and that "... the aggregate set of the specified elements is treated as a column vector", which means that c(basis) produces a column vector.
In the old RPG III and the non-free RPGLE/RPG IV you could "rename" fields you get from either a record of a PF/LF or a record from a DSPF.
This lead to possibilities like grouping several lines of input (additional order text) into a array. So I didn't have to MOVEL or EVAL ottxt1 to the external described field x1txt1, ottxt2 to x1txt2 and so on.
I'd only had to rename the LF record and the DSPF record fields to the array-fields, read the record and shift them from the one array to the other and display my DSPF record
H DECEDIT('0,') DATEDIT(*DMY.) dftactgrp(*no)
Fsls001 cf e workstn
Fordtxtl0 if e k disk
D ot s 20a dim(6)
D x1 s 20a dim(6)
Iordtxtr
I ottxt1 ot(1)
I ottxt2 ot(2)
I ottxt3 ot(3)
I ottxt4 ot(4)
I ottxt5 ot(5)
I ottxt6 ot(6)
Isls00101
I x1txt1 x1(1)
I x1txt2 x1(2)
I x1txt3 x1(3)
I x1txt4 x1(4)
I x1txt5 x1(5)
I x1txt6 x1(6)
C k$or00 klist
C kfld otonbr
C kfld otopos
C eval otonbr = 2
C eval otopos = 2
C k$or00 chain ordtxtr
C if %found(ordtxtl0)
C eval x1 = ot
C endif
C
C exfmt sls00101
C
C move *on *inlr
But is this also possible in *FREE RPGLE? And if so, how?
You can define data structures containing the fields from the files, and overlay them with an array.
Replace your I specs and array definitions with these data structures. You don't have to specify anything besides the field names for the fields from the externally-described file.
dcl-ds otDs;
ottxt1;
ottxt2;
ottxt3;
ottxt4;
ottxt5;
ottxt6;
ot like(ottxt1) dim(6) pos(1);
end-ds;
dcl-ds x1Ds;
x1txt1;
x1txt2;
x1txt3;
x1txt4;
x1txt5;
x1txt6;
x1 like(x1txt1) dim(6) pos(1);
end-ds;
I would like to print the function definition of any nested function when printing the definition of the outer function. Example:
g:{sin x}
f:{cos g x}
When I print f I get {cos g x} but I want to get {cos {sin x} x}
Thanks for the help
From what I am aware it is not possible to achieve that with in-build functions.
You can attempt to write your own function that does that but it will be a pain in the end. Something like this maybe:
q)m:string[v]!string value each v:value[f][3] except `
which creates a dictionary m :
q)m
,"g"| "{sin x}"
When given a function value returns a list containing (bytecode;parameters;locals(context;globals);constants[0];...;constants[n];definition)
However, if we pass a symbol to value it returns the value of that symbol (or function definition in this case).
You can then use ssr to replace the functions in f with the function definitions stored in your dictionary m.
q)ssr/[last value[f];key m;value m]
"{cos {sin x} x}"
but to ensure that your function is stable and adaptable to different functions would be very difficult.
For more details about how value have a look here: https://code.kx.com/q/ref/metadata/#value
For ssr check this link:
https://code.kx.com/q/ref/strings/#ssr
I am going to start illustration using a code:
A = 'G1(General G1Airlines american G1Fungus )';
Using regexp (or any other function) in Matlab I want to distinctively locate: G1, G1A and G1F.
Currently if I try to do something as:
B = regexp( A, 'G1')
It is not able to distinguish G1 with the G1A and G1F i.e. I need to force the comparison to find me only case with G1 and ignore G1A and G1F.
However, when I am searching for G1A then it should still find me the location of G1A.
Can someone please help ?
Edit: Another case for A is:
A = 'R1George Service SmalR1Al C&I)';
And the expression this time I need to find is R1 and R1A instead.
Edit:
I have a giant array containing A's and another big vector containing G1, R1, etc I need to search for.
If you want to find 'G1' but not 'G1A' or 'G1F' you can use
>> B = regexp(A, 'G1[^AF]')
B =
1
This will find 'G1' and the ^ is used to specify that it should not match any characters contained with []. Then you could use
>> B = regexp(A, 'G1[AF]')
B =
12 32
to find both 'G1A' and 'G1F'.
I saw some pseudocode in some old exam and I can't really figure out what it's doing.
Can anyone explain it to me?
A and B are BST's.
Foo(A,B)
if A= NULL
return B
if B != NULL
if value[A] > value[B]
return Foo(B,A)
left[B] <- Foo(right[A],left[B])
right[A] <- B
return A
This is a binary search tree merge routine. If either A or B is null (representing an empty tree), it returns the other. Otherwise, it makes sure that the root of A is less than the root of B; if the roots are in the wrong order, it recurses with the arguments swapped. Then, it recursively merges the right subtree of A and the left subtree of B, and attaches the result as the left subtree of B. Finally, it attaches B as the new right subtree of A and returns A.