How can I preallocate this script code to speed?

How can I preallocate this script code to speed?

%get GPS/MEAS lines

clc

clear ALL

File_ID_1 =fopen('C:\Users\Eman Abdelrazeq\Desktop\gLAB documments\gLab function\dataMO_ME.out');

if File_ID_1< 0

fprintf('File does not exist')

end

ind=0;

%MEAS_MATRIX=ones(31917,9);

for i=1:239522

line_MEAS=fgets(File_ID_1);

if line_MEAS(1:4)=="MEAS" && line_MEAS(29:31)=="GPS"

ind=ind+1;

YEAR(ind,1)=str2double(line_MEAS(11:14));

DAY(ind,2)=str2double(line_MEAS(16:18));

SECOND(ind,3) =str2double(line_MEAS(20:27));

PRN(ind,4)=str2double(line_MEAS(33:34));

ELEVATION(ind,5)=str2double(line_MEAS(38:43));

AZMUTH(ind,6) =str2double(line_MEAS(45:52));

C1C(ind,7)=str2double(line_MEAS(107:119));

C1P(ind,8)=str2double(line_MEAS(137:149));

C2P(ind,9)=str2double(line_MEAS(167:179));

MEAS_MATRIX(ind,1)=YEAR(ind,1);

MEAS_MATRIX(ind,2)=DAY(ind,2);

MEAS_MATRIX(ind,3)= SECOND(ind,3);

MEAS_MATRIX(ind,4)= PRN(ind,4);

MEAS_MATRIX(ind,5)= ELEVATION(ind,5);

MEAS_MATRIX(ind,6)= AZMUTH(ind,6);

MEAS_MATRIX(ind,7) = C1C(ind,7);

MEAS_MATRIX(ind,8)= C1P(ind,8);

MEAS_MATRIX(ind,9)=C2P(ind,9);

end

end

fclose( File_ID_1);

Also why if I add (while ~feof(File_ID_1) At the begining befor ( for loop) it give me this error

Index exceeds the number of array elements (1).

Error in MEAS_DATA (line 20)

if line_MEAS(1:4)=="MEAS" && line_MEAS(29:31)=="GPS"

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