MATLAB: How to create a .mat file

Question

I am trying to create NewTemplates.mat file

I got an error as

*Error using horcat

Dimensions of matrices being concatenated are not consistent.

Error in

letter=[A Afill B Bfill C D Dfill E F G H I J K L M…*

code I used to create .mat file is

%CREATE TEMPLATES

%Letter

A=imread('A.bmp');B=imread('B.bmp');

C=imread('C.bmp');D=imread('D.bmp');

E=imread('E.bmp');F=imread('F.bmp');

G=imread('G.bmp');H=imread('H.bmp');

I=imread('I.bmp');J=imread('J.bmp');

K=imread('K.bmp');L=imread('L.bmp');

M=imread('M.bmp');N=imread('N.bmp');

O=imread('O.bmp');P=imread('P.bmp');

Q=imread('Q.bmp');R=imread('R.bmp');

S=imread('S.bmp');T=imread('T.bmp');

U=imread('U.bmp');V=imread('V.bmp');

W=imread('W.bmp');X=imread('X.bmp');

Y=imread('Y.bmp');Z=imread('Z.bmp');

Afill=imread('fillA.bmp');

Bfill=imread('fillB.bmp');

Dfill=imread('fillD.bmp');

Ofill=imread('fillO.bmp');

Pfill=imread('fillP.bmp');

Qfill=imread('fillQ.bmp');

Rfill=imread('fillR.bmp');

M1=imread('M2.jpg');

%Number

one=imread('1.bmp'); two=imread('2.bmp');

three=imread('3.bmp');four=imread('4.bmp');

five=imread('5.bmp'); six=imread('6.bmp');

seven=imread('7.bmp');eight=imread('8.bmp');

nine=imread('9.bmp'); zero=imread('0.bmp');

zerofill=imread('fill0.bmp');

fourfill=imread('fill4.bmp');

sixfill=imread('fill6.bmp');

sixfill2=imread('fill6_2.bmp');

eightfill=imread('fill8.bmp');

ninefill=imread('fill9.bmp');

ninefill2=imread('fill9_2.bmp');

fillone=imread('1fill.jpg');

filltwo=imread('2fill.jpg');

fillfour=imread('4fill.jpg');

%*-*-*-*-*-*-*-*-*-*-*-

letter=[A Afill B Bfill C D Dfill E F G H I J K L M…

    N O Ofill P Pfill Q Qfill R Rfill S T U V W X Y Z M1];

number=[one two three four fourfill five…

    six sixfill sixfill2 seven eight eightfill nine ninefill ninefill2 zero zerofill fillone 
filltwo fillfour];

character=[letter number];

NewTemplates=mat2cell(character,42,[24 24 24 24 24 24 24 24 … 24 24 24 24 24 24 24 … 24 24 24 24 24 24 24 … 24 24 24 24 24 24 24 … 24 24 24 24 24 24 24 … 24 24 24 24 24 24 24 … 24 24 24 24 24 24 24]);

save ('NewTemplates','NewTemplates')

clear all

Answer 1

Well, since it says their sizes don't match for stitching together horizontally, what are the numbers of rows for all these: A Afill B Bfill C D Dfill E F G H I J K L M...