Why does a working standalone nested function/script not work inside a larger script? [duplicate]

The following (nested) function/s

function hpf_matrix { # Positional Parameters Matrix_Dimension="${1}" Center_Cell_Value="${2}" # Define the cell value(s) function hpf_cell_value { if (( "${Row}" == "${Col}" )) && (( "${Col}" == `echo "( ${Matrix_Dimension} + 1 ) / 2" | bc` )) then echo "${Center_Cell_Value} " else echo "-1 " fi } # Construct the Row for Cols 1 to "Matrix_Dimension" function hpf_row { for Col in `seq ${Matrix_Dimension}` do echo -n "$(hpf_cell_value)" done } # Construct the Matrix echo "MATRIX ${Matrix_Dimension}" for Row in `seq ${Matrix_Dimension}` do echo "$(hpf_row)" done echo "DIVISOR 1" echo "TYPE P" } 

work/s fine, both as a standalone code and inside a script. I.e. hpf_matrix 5 18 will return

MATRIX 5 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 18 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 DIVISOR 1 TYPE P 

and it will even work (with various values) as requested in:

Kernel_Size=5 Center_Cell_Default=18 ; Center_Level=Default eval Center_Cell="Center_Cell_${Center_Level}" HPF_MATRIX_ASCII=`hpf_matrix ${Kernel_Size} ${!Center_Cell}` echo "${HPF_MATRIX_ASCII}" 

However, integrating without any changes the above pieces of code (the hpf_matrix function and feeding the "${HPF_MATRIX_ASCII}") inside a larger bash script, errors-out with the following message:

((: 1 2 3 4 5 == 1 2 3 4 5 : syntax error in expression (error token is "2 3 4 5 == 1 2 3 4 5 ") 

Minor Update

If I understand correctly, for whatsoever is the reason behind, the line

for Row in seq ${Matrix_Dimension}

as well as the line

for Col in seq ${Matrix_Dimension}

are printed as "1 2 3 4 5" instead of "1" "2" "3" "4" "5".

What is wrong in this case? I would like to keep a nested structure for the function unless it is clearly wrong.