Row interpolation by adding data at end of the matrix

I have a variable d which is a row matrix of 1x18

d=[24.1615256950601 24.1615256699363 24.1615256438020 24.1615256182430 24.1615256053197 24.1615255801960 24.1615255672726 24.1615255402679 24.1615255131230 24.1615255004873 24.1615254753636 24.1615254509627 24.1615254248284 24.1615254114699 24.1615253988342 24.1615253870690 24.1615253734228 24.1615253590537]

I want to extend the length of the matrix to 1x20. If I am using interp1 it's showing NAN at pos 19,20.

I want to extend the curve to 20 points how should I do it...???

Answer 1

[Stephen23]

>> V = interp1(1:18,d,1:20,'pchip','extrap');
>> V(:)
ans =
   24.1615256950601
   24.1615256699363
   24.1615256438020
   24.1615256182430
   24.1615256053197
   24.1615255801960
   24.1615255672726
   24.1615255402679
   24.1615255131230
   24.1615255004873
   24.1615254753636
   24.1615254509627
   24.1615254248284
   24.1615254114699
   24.1615253988342
   24.1615253870690
   24.1615253734228
   24.1615253590537
   24.1615253439804
   24.1615253282587

[Abhiraj Gupta]

Thank you very much for the help.