How to interpolate between values in columns of an array without a for loop

I have an n-by-1 vector of x values and an n-by-m array of y values. I would like to get m interpolated y values for an arbitrary value in the range of the given x vector.

Can this be done as an array operation? It feels wrong to use a for-loop in Matlab to step through the columns of an array.

[Bruce Elliott]

Never mind!! The y values can be a matrix or an array - my mistake!

Answer 1

[Matt J]

You should use interp1. It's very straightforward.

[m,n]=deal(8,5);

x=(1:n)';
y=reshape(1:m*n,n,m)

y = 5×8

1 6 11 16 21 26 31 36 2 7 12 17 22 27 32 37 3 8 13 18 23 28 33 38 4 9 14 19 24 29 34 39 5 10 15 20 25 30 35 40

yq=interp1(x,y,[1.5;2.5;3.5])

yq = 3×8

1.5000 6.5000 11.5000 16.5000 21.5000 26.5000 31.5000 36.5000 2.5000 7.5000 12.5000 17.5000 22.5000 27.5000 32.5000 37.5000 3.5000 8.5000 13.5000 18.5000 23.5000 28.5000 33.5000 38.5000

[Bruce Elliott]

Whoops! Right after I posted this I realized that the y values can be a matrix or array. I had looked only at the input for x. Sorry!!