Reading specific parts of a text file in PHP.

[vidyashankara]

I have a text file named 123.pdb. It contains
[code]
HEADER    LIPID TRANSPORT                         23-SEP-97   1AV1              
TITLE     CRYSTAL STRUCTURE OF HUMAN APOLIPOPROTEIN A-I                        
COMPND    MOL_ID: 1;                                                            
COMPND   2 MOLECULE: APOLIPOPROTEIN A-I;                                        
COMPND   3 CHAIN: A, B, C, D;                                                  
COMPND   4 FRAGMENT: LIPID-BINDING DOMAIN;                                      
COMPND   5 SYNONYM: APO A-I;                                                    
COMPND   6 ENGINEERED: YES;                                                    
COMPND   7 MUTATION: N-TERMINAL MET, DEL(1-43)                                  
SOURCE    MOL_ID: 1;                                                            
SOURCE   2 ORGANISM_SCIENTIFIC: HOMO SAPIENS;                                  
SOURCE   3 ORGANISM_COMMON: HUMAN;                                              
SOURCE   4 TISSUE: BLOOD;                                                      
SOURCE   5 EXPRESSION_SYSTEM: ESCHERICHIA COLI;                                
SOURCE   6 EXPRESSION_SYSTEM_STRAIN: BL21 (DE3);                                
SOURCE   7 EXPRESSION_SYSTEM_VECTOR_TYPE: PLASMID;                              
SOURCE   8 EXPRESSION_SYSTEM_VECTOR: PGEMEX                                    
KEYWDS    LIPOPROTEIN, LIPID TRANSPORT, CHOLESTEROL METABOLISM,                
KEYWDS   2 ATHEROSCLEROSIS, HDL, LCAT-ACTIVATION                                
EXPDTA    X-RAY DIFFRACTION  
[/code]

I am writing a code to read this file and echo the output. Like.
[code]
Description:

Name: CRYSTAL STRUCTURE OF HUMAN APOLIPOPROTEIN A-I
PDB ID : 1av1
Number of Chains: A, B, C, D;
Experimental Method: X-RAY DIFFRACTION
[/code]

I have the following code.
[code]
$id = $_GET["file"];
$file = "$id.pdb";
$contents = file_get_contents($file);
$title=  preg_replace('/^(?!TITLE).*?(?:\n|$)/m','',$contents);
$exp=  preg_replace('/^(?!EXPDTA).*?(?:\n|$)/m','',$contents);
$chain=  preg_replace('/^(?!COMPND   3 CHAIN:).*?(?:\n|$)/m','',$contents);

echo "Description:<p>";

echo "Name: $title<br>";
echo "PDB ID : $id<br>";
echo "Number of Chains: $chain<br>";
echo "Experimental Method:$exp<br>";
[/code]

This outputs
[code]
Description:

Name: TITLE CRYSTAL STRUCTURE OF HUMAN APOLIPOPROTEIN A-I
PDB ID : 1av1
Number of Chains: COMPND 3 CHAIN: A, B, C, D;
Experimental Method:EXPDTA X-RAY DIFFRACTION
[/code]

Basically the script reads the line starting with TITLE, COMPND 3 CHAIN and EXPDTA to get this information. what do i modify in the script to omit these words? the script should just show
Name: CRYSTAL STRUCTURE OF HUMAN APOLIPOPROTEIN A-I
instead of
Name: TITLE CRYSTAL STRUCTURE OF HUMAN APOLIPOPROTEIN A-I
The starting word TITLE should be omitted.

If i say
READ from 123.pdb. The lines starting from TITLE, It must output what comes after TITLE, not the whole line.

Any help would be appreciated!
Thanks
Vidyashankara

[vidyashankara]

I got it, just replaced the text with a space :)