bitshift Double inputs error

I use this command where A is a 4x4 array and "s" is a dobule (actually it's value is 18.000)

I assume the inputs as int64, then why I get error "Double inputs must have integer values in the range of ASSUMEDTYPE" ?

W = bitshift(A,s-15,'int64');

whos A prints: " A 4x4 128 double "

Edit: I changed the command to "W = bitshift(int64(A),int64(s-15),'int64');"

But is the way to do it ?

Answer 1

[KALYAN ACHARJYA]

A=randi(10,[4 4]);
s=18;
W = bitshift(A,s-15,'int64')

Result:

W =
    40    56    32    72
    32    16    80    72
    64     8    80    48
    64    48    24    72

Documentation: If A is an array of signed integers, then bitshift returns the arithmetic shift results, preserving the signed bit when k is negative, and not preserving the signed bit when k is positive.

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