Linearly "interpolate" a 1-dimensional vector

1 view (last 30 days)
Hello,
I have a vector of annual population figures for a number of years. I'd like to assume a linear growth and obtain the implied weekly figures. Is there an easier way than using interp1 and having to create an x grid of the years [1 2 3...] and the query points [1/52 2/52....1, 1 1/52, 1 2/52....]? Something like
[pop,txt,raw]= xlsread('annual population.xlsx');
pop=pop(:,1:2);
weekpop=[];
for i=1:21 %1997-2017 21 years
weekpop=[weekpop; linspace(pop(23-i,2),pop(23-1-i,2),52)'];
end
sort of works but doing linspace on a vector of values duplicates the end points (the pop in the 52nd week of year t-1 is the same as pop in week 1 of year t)
Thank you!

Accepted Answer

Jan
Jan on 13 Feb 2019
What's wrong with interp1?
pops = flipud(pop(:,2));
n = numel(pops);
weekpop = interp1(1:n, pops, linspace(1, n, (n-1) * 52))
  2 Comments
wy6622
wy6622 on 13 Feb 2019
I wasn't able to come up with an elegant way to write the query points like your "linspace(1, n, (n-1) * 52)". Thank you!

Sign in to comment.

More Answers (0)

Categories

Find more on Creating and Concatenating Matrices in Help Center and File Exchange

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!